Field of Science

Showing posts with label Palpatores. Show all posts
Showing posts with label Palpatores. Show all posts

Platybunus: the Wide-Eyed Harvestmen of Europe

The western Palaearctic region (that is, Europe and the immediately adjacent parts of Asia and northern Africa) is home to a diverse and distinctive fauna of harvestmen. Among the various genera unique to this part of the world are the forest- and mountain-dwellers of the genus Platybunus.

Platybunus pinetorum, copyright Donald Hobern.


Platybunus species are moderate-sized long-legged harvestmen of the family Phalangiidae, the central body in larger individuals being about eight millimetres long (Martens 1978). Their most characteristic feature is a relatively large eye-mound, distinctly wider than long and occupying a large section of the anterior carapace. As with other European phalangiids, they eye-mound is ornamented with a row of denticles each side though the body lacks denticles over the remainder of the dorsum. The body is often comparatively slender, tapering towards the rear (particularly in males), and is marked on the dorsum by a darker median band. The pedipalps have a pair of well-developed setose apophyses on the inner distal ends of the patella and tibia, and a series of long spine-like tubercles on the underside of the femur. These tubercles presumably function in the capture of prey, forming a basket that can be closed around the harvestman's victims. External sexual dimorphism in Platybunus is fairly minimal though females are overall larger and fatter. The penis is notably long and slender with a relatively small glans, offset from the shaft by a more or less marked constriction.

Platybunus bucephalus, copyright Adrian Tync.


Martens (1978) recognises four species of Platybunus found in higher altitude regions of central Europe with the species P. bucephalus and P. pinetorum occupying much of the genus' range. Platybunus bucephalus may be distinguished from P. pinetorum by, among other features, its relatively shorter legs. Platybunus pallidus is endemic to the Carpathians, and the tiny P. alpinorelictus inhabits the Garda Mountains of northern Italy. Another species, P. anatolicus, was described from Turkey by Roewer (1956)*. In general, Platybunus species inhabit alpine and subalpine forests, being found among the herbaceous undergrowth, under bark or on rock faces. Where their ranges overlap, P. bucephalus is more accustomed to extending beyond the forest margins than P. pinetorum and may be found above the tree-line. In recent years, the range of P. pinetorum has extended northwards, being first recorded from the UK in 2010 and Sweden in 2015 (Fritzén et al. 2015). At least some populations of P. pinetorum are capable of reproducing parthenogenetically and this may have played a part in its spread.

*Platybunus mirus was described by Loman (1892) on the basis of two male specimens that supposedly came from Sumatra. Though the identity of this species has never been resolved (Loman's illustration of the penis is at least suggestive of a true Platybunus), the claimed locality seems almost certain to be an error of some kind.

The internal classification of the Phalangiidae remains in need of further investigation. Platybunus has been recognised by some authors as forming a subfamily Platybuninae with a cluster of other western Palaearctic genera bearing similar ventrally spined pedipalps (Zhang & Zhang 2012). However, other authors have not separated this group from the subfamily Phalangiinae. The platybunines may represent a phylogenetically coherent grouping, or their shared features may reflect adaptations to a similar life style. The genital morphology of Platybunus is recognisably distinct from that of other platybunines which may argue against any relationship (Martens 1978). On the other hand, platybunines might possibly be distinguished from phalangiines by the chemical composition of their repugnatorial gland secretions (Raspotnig et al. 2015). A formal analysis of the family's evolution would be a welcome advance.

REFERENCES

Fritzén, N. R., V. Rinne, M. Sunhede, A. Uddström, S. Van de Poel & P. De Smedt. 2015. Platybunus pinetorum (Arachnida, Opiliones) new to Sweden. Memoranda Soc. Fauna Flora Fennica 91: 37–40.

Loman, J. C. C. 1892. Opilioniden von Sumatra, Java und Flores. In: M. Weber (ed.) Zoologische Ergebnisse einer Reise in Niederländisch Ost-Indien vol. 3 pp. 1–26, pl. 1. E. J. Brill: Leiden.

Martens, J. 1978. Spinnentiere, Arachnida: Weberknechte, Opiliones. Gustav Fischer Verlag: Jena.

Raspotnig, G., M. Schaider, P. Föttinger, V. Leutgeb & C. Komposch. 2015. Benzoquinones from scent glands of phalangiid harvestmen (Arachnida, Opiliones, Eupnoi): a lesson from Rilaena triangularis. Chemoecology 25: 63–72.

Roewer, C. F. 1956. Über Phalangiinae (Phalangiidae, Opiliones Palpatores). (Weitere Weberknechte XIX). Senckenbergiana Biologica 37 (3–4): 247–318.

Zhang, C., & F. Zhang. 2012. On the subfamilial assignment of Platybunoides (Opiliones: Eupnoi: Phalangiidae), with the description of a new species from China. Zootaxa 3190: 47–55.

Pseudogagrella: A Harvestman Torn

The Sclerosomatidae are one of the most diverse of the currently recognised harvestmen families, and one of the most problematic when it comes to classification. In various earlier posts, I have noted the challenges that bedevil sclerosomatid systematics, many reflecting a historical focus on superficial external features of questionable evolutionary significance. Perhaps no taxon more neatly exemplifies the problems with higher sclerosomatid classification than the eastern Asian genus Pseudogagrella.

Pseudogagrella sakishimensis, copyright Tomoya Suzuki.


Historically, the greater number of sclerosomatids have been divided between two major subfamilies, the Leiobuninae and Gagrellinae. The Leiobuninae have mostly been recognised as living in the northern temperate regions whereas the Gagrellinae were mostly tropical. The division between the two subfamilies has long been regarded as more than a little fuzzy, and has usually hinged on a single feature: the presence (Gagrellinae) or absence (Leiobuninae) of rings of flexible integument (noduli) in the femora of the legs. Pseudogagrella is a genus of sclerosomatid harvestmen recognised from Japan, Taiwan, China and Sumatra (Chen & Shih 2017). Members of this genus lack leg noduli so have historically been included in the Leiobuninae. The problem is that their overall appearance, with a tendency to bold coloration, a tall median spine rising from the hardened scute covering most of the abdomen, and legs that are not merely long but ludicrously so (even by harvestman standards), is extremely similar to species of Gagrellinae. So much so, in fact, that some species currently placed in Pseudogagrella were long included in the archetypical gagrelline genus, Gagrella (Suzuki 1977).

With the distinction between the two subfamilies being so vague, I don't think it really came as that much surprise to anyone when molecular phylogenetics underlined the need for a thorough re-working of sclerosomatid systematics. Though the analysis conducted by Hedin et al. (2012) did not support the prior distinction between 'leiobunines' and 'gagrellines', it did suggest the existence of distinct lineages occupying distinct geographical regions. One species of Pseudogagrella included in the analysis (the southern Japanese P. amamiana) was placed in a cluster of eastern Asian species including other Asian 'gagrellines', but also the 'leiobunine' 'Leiobunum' japonicum. So it seems likely that, should subfamilies of Sclerosomatidae continue to be recognised, Pseudogagrella will indeed be a member of Gagrellinae, but Gagrellinae itself shall not quite be what people think of it as being.

Pseudogagrella dorsomaculata, copyright Tyus Ma.


There is also, of course, the question of whether Pseudogagrella itself is a coherent unit. Hedin et al. (2012) included only the one Pseudogagrella species in their analysis and the need for an extensive revision of the Asian sclerosomatid genera still remains. A study of Chinese species assigned to the genus Melanopa (Zhang & Zhang 2013), which is primarily distinguished from Gagrella by having relatively shorter legs, suggested the possibility of this 'genus' being divided between groups of Palaearctic and Indo-Malayan species, and I've wondered if this division might carry further (unfortunately, I'm not aware of any Indo-Malayan 'gagrellines' being included in molecular phylogenies; I think all the Asian species covered by Hedin et al. were Palaearctic). The majority of Pseudogagrella species, found in Japan and Taiwan, can be comfortably compared to other sclerosomatids from that region, but the Sumatran P. multimaculata, and possibly the southern Chinese species, might turn out to be closer to their own geographical peers. As always, a great deal of research remains to be done.

REFERENCES

Chen, S.-L., & H.-T. Shih. 2017. Descriptions of three new species of the harvestmen genus Pseudogagrella (Opiliones: Sclerosomatidae: Gagrellinae) from Taiwan, supported by morphological and molecular evidence. Zootaxa 4268 (1): 34–52.

Hedin, M., N. Tsurusaki, R. Macías-Ordóñez & J. W. Shultz. 2012. Molecular systematics of sclerosomatid harvestmen (Opiliones, Phalangioidea, Sclerosomatidae): geography is better than taxonomy in predicting phylogeny. Molecular Phylogenetics and Evolution 62 (1): 224–236.

Suzuki, S. 1977. Opiliones from Taiwan (Arachnida). Journal of Science of the Hiroshima University, Series B, Division 1 (Zoology) 27 (1): 121–157.

Zhang, C., & F. Zhang. 2013. Notes on some species of the genus Melanopa (Opiliones: Sclerosomatidae: Gagrellinae) from China, with description of a new species. Journal of Arachnology 41: 306–318.

Rhampsinitus Re-Redux

I've featured the African harvestman genus Rhampsinitus on this site twice before, but I'm going to have another dive into it today. There's still more I can say about this remarkable genus.

Male Rhampsinitus, possibly R. leighi, copyright Peter Vos. The individual ahead of the male is another Rhampsinitus, probably a female; there's also a short-legged harvestmen beneath the male.


There's more I could say about African phalangiids in general, in fact. There's never been a proper phylogenetic study of the long-legged harvestman family Phalangiidae, so we can't speak with confidence about the relationships between the African members of this group and their relatives elsewhere, but it would not be unexpected if the sub-Saharan phalangiids form an evolutionarily coherent group. Many of the family's most striking exemplars are to be found on the African continent: Cristina with their thick, spiky front legs; sleek, flattened Odontobunus, Guruia with their chelicerae like a pair of jar tongs held in a boxing glove. Rhampsinitus' current position as the best-known African harvestman genus is probably due not only to its diversity but also to its more temperate centre of distribution placing it closer to researchers than these other more equatorial genera.

As mentioned in my first post on the genus, there are currently over forty recognised species of Rhampsinitus. As alluded to in my second post, that number might be expected to change in the future. No reliable identification key is currently available for Rhampsinitus, nor is the information available for many species that would allow such a key to be written. A key to the southern African species was provided by Kauri (1961) but, while I did find this key invaluable when I conducted my own tentative foray into rhampsinitology, I couldn't recommend it to a novice. Kauri was simply unaware of the extreme variation that can be found among male Rhampsinitus belonging to a single species. There are only a handful of species for which both major and minor males have been described and, as I explained previously, minor males may not be identifiable to species without examining genitalia.

Probably a male Rhampsinitus vittatus, copyright Nanna.


This, obviously, is a problem for the handful of species that have been described from what appear to be minor males. Some of these, such as Rhampsinitus fissidens and R. hewittius, are probably doomed to remain mysteries at least until someone redescribes their types. Others may be more recognisable. Rhampsinitus qachasneki is an unusually spiny species described from the mountains of Lesotho, with some of the denticles along the front edge of the body multi-pointed. These distinctive denticles, like repurposed muntjak antlers, might reasonably be expected to be present in any major males of this species, if they exist. The challenge may be even greater for the handle of species that have been described from females. Nevertheless, the known female of R. maculatus, another Lesotho mountain species, has a distinctive spotted colour pattern and thick, remarkably hairy pedipalps that might be expected to show their analogues in the unknown males (again, if they exist: we're kind of glossing over the point that some harvestmen species are known to be parthenogenetic, because harvestmen systematics is so heavily predicated on male genital morphology that the idea of an all-female harvestman species is a trifle intimidating*).

*I assume that this is precisely what Zappa had in mind when he got to the end of Thing-Fish.

Then, of course, there's the persistent question of Rhampsinitus lalandei. This was the first species included in Rhampsinitus in 1879 and as such represents the type or sine qua non of the genus. As was not unusual for the time, its author Eugene Simon was a bit vague about where his original specimen(s) had come from, giving the locality as simply 'Cafrerie'. Cafrerie, rendered in English as Kaffraria or Kaffirland, is a geographical designation that has fallen out of favour these days for reasons I would hope to be obvious, but was commonly used during the 1800s to refer to the area around the eastern coast of modern South Africa, particularly around Port Elizabeth. Unfortunately, Simon's description of R. lalandei is not definitive by modern standards—most of the features described could apply to any number of Rhampsinitus species—and Simon's original specimen appears to have been lost. This presents a problem for any who would suggest that this large genus should be divided up as it might become uncertain which division represents the true Rhampsinitus. Starega (2009) suggested that R. lalandei might be the same as R. crassus, a species definitely found in the Port Elizabeth region. However, it should be noted that Simon described R. lalandei as being irregularly armed with denticles dorsally. In the majority of Rhampsinitus species, the denticles on the opisthosoma form very neat transverse rows, but in others they are a bit more messily placed. Rhampsinitus crassus is one of the former species but the description of R. lalandei suggests it may have been one of the latter. So if anyone's looking at harvestmen from around that area, keep your eyes open.

REFERENCES

Kauri, H. 1961. Opiliones. In: Hanström, B., P. Brinck & G. Rudebeck (eds) South African Animal Life: Results of the Lund University Expedition in 1950–1951 vol. 8 pp. 9–197. Almqvist & Wiksells Boktryckeri Ab: Uppsala.

Staręga, W. 2009. Some southern African species of the genus Rhampsinitus Simon (Opiliones: Phalangiidae). Zootaxa 1981: 43-56.

Publication date of Bulletin de la Société Philomathique

I should say up front, this is going to be a pretty esoteric one. It's just that this is something I spent a fair chunk of a morning trying to work out, and I may as well put what I found up here in case someone else finds it useful.

A few weeks back I found myself, as one does, trying to sort out the exact publication date of early numbers of the Bulletin des Sciences, par la Societé Philomathique de Paris, which has been archived online at the Biodiversity Heritage Library. The Société Philomathique was an association of French scientists and polymaths from a wide range of disciplines founded in 1788. You can find the webpage for the current iteration of the Société here. In 1791, the Societé decided to circulate a bulletin of abstracts of their meetings, including summaries of papers and letters presented there.

The title page of the volume of the Bulletin available at the Biodiversity Heritage Library gives the dates of "Juillet 1791, a Ventôse, An 7", or July 1791 to February–March 1799, which is the dates of the meetings presented therein ("Ventôse, An 7" is a date in the Republican Calendar that was introduced for a period following the establishment of the French Republic in 1792). Citations I could initially find for individual notices in the Bulletin were all attributed to dates of the separate meetings that they were presented at (e.g. something presented at the May 1794 meeting would be cited as "1794"). But it was immediately obvious to me that the notices could not have been published at the times of the original meetings, at least not as they appeared in the volume reproduced, because abstracts from separate meetings would appear on the same page! Hence my search for information on the Bulletin's actual publication date: were notices for individual meetings issued separately at the time, or did they not actually appear in print until the subsequent publication (presumably in 1799 or even later) of the collected volume? I should note that some of the abstracts in the Bulletin included descriptions of new species, so the question of publication date could have further taxonomic implications.

A page from the collated Bulletin, showing how the last entry for the December 1792 meeting is followed immediately by the section for January 1793, without a page-break for originally separate issues to have been collected together.


Eventually, I was able to establish that separate Bulletin issues had indeed been released for each meeting (you can see reproductions of the uncollated originals at Gallica). However, there is a complication. Early issues of the Bulletin were written by hand, and distributed only to the members of the Société (about 18 people at the time). It was not until November 1792 that a printed version of the Bulletin began to be disseminated more widely. Now, the International Code of Zoological Nomenclature requires that any publication for taxonomic purposes produced before 1986 must "have been produced in an edition containing simultaneously obtainable copies by a method that assures...numerous identical and durable copies" (Article 8.1.3). A handwritten manuscript would not meet that requirement, so any zoological name appearing in those early bulletins would not count as published. They would not become established until the subsequent publication of the collated volume, which according to an introduction written by Jonathan Mandelbaum in 1977 for a bound collection of the original Bulletin issues (reproduced at Gallica here) happened in 1802.

Original first page of the Bulletin for January 1793. As well as the separation from the December entries, note that the first entry of the original version has been omitted from the collated version, and that the title's original spelling said 'Philomatique' rather than 'Philomathique'.


As an example of the sort of consequences that might arise from this, consider Odiellus spinosus, a widespread harvestman species found in western Europe. This species was very briefly described, as Phalangium spinosum, by Bosc in 1792 in one of the manuscript issues of the Bulletin de la Societé Philomatique (the February 1792 one, to be exact). This has uniformly been accepted as the publication date, but Bosc's species was not properly published until 1802. This might be a simple question of book-keeping, were it not that, in the meantime, Latreille (1798) had used the name 'Phalangium spinosum' for a quite different harvestman species, and described what is now known as 'Odiellus spinosus' under the name of 'Phalangium histrix'. So strict application of the law of priority means that the species in question should be known as Odiellus histrix.

Fortunately, in this case there may be some loopholes available to us. Latreille's names both have strict priority over Bosc's, but they may each count as nomina oblita ('forgotten names'). This is a provision in the ICZN that a name that has not been used as valid since before 1899 can be set aside in favour of a more widely recognised junior synonym if "the junior synonym or homonym has been used for a particular taxon, as its presumed valid name, in at least 25 works, published by at least 10 authors in the immediately preceding 50 years and encompassing a span of not less than 10 years" (ICZN Art. 23.9.1.2). Latreille's Phalangium spinosum was soon recognised as a synonym of an earlier name, and was last used as valid in 1802. Phalangium histrix (or derived combinations thereof) persisted in the literature for longer, but I haven't come across it being used as a separate species after 1876. The open question is whether Bosc's name has been used often enough to warrant automatic conservation. I suspect it would have (I haven't done a proper tally myself, but a search for 'Odiellus spinosus' on Google Scholar brings up about 130 results) but, if not, then an appeal to the ICZN would be required if we wanted to keep using the current name for the species.

Long-legged Harvestmen of Southern Africa

New paper time!

Rhampsinitus conjunctidens, a new species of harvestmen from north-east South Africa, from Taylor (2017).


Taylor, C. K. 2017. Notes on Phalangiidae (Arachnida: Opiliones) of southern Africa with description of new species and comments on within-species variation. Zootaxa 4272 (2): 236–250.

When I first started research for my PhD thesis, *cough* years ago, I asked a number of museums if they could loan me their collections of monoscutid (now neopilionid) harvestmen. The species that I was interested in are found in Australia and New Zealand but when I opened a package of specimens sent to me from the California Academy of Sciences, I found a number of specimens from Africa in the mix. I immediately recognised what they were: not neopilionids, but representatives of another harvestment family, the Phalangiidae.

It seemed an easy enough error to make. Many species of southern African Phalangiidae resemble a lot of neopilionids in that the males have over-sized, elongate chelicerae. I referred to some of these species in the genus Rhampsinitus in an earlier post. To those not familiar with harvestmen diversity (which, let's face it, is the majority of people out there), the two groups can look very similar. True, the phalangiids are all distinctly much spikier than the neopilionids, but that doesn't seem that major a difference. To really see where they diverge from each other, you need to reach underneath the males' genital opercula and pull out their todgers.

Anywho, the specimens sat in storage for much longer than they should have, until I finally got around to looking them over in the latter part of last year. I then decided that it was worth writing them up into a short paper. Not only was there at least one new species among the specimens, they told me some very interesting things about variation within the species. Not only do Rhampsinitus species resemble Australasian neopilionids in their enlarged chelicerae, they resemble them in that individuals of a species vary in how enlarged the chelicerae are.

Major (left) and minor males of Rhampsinitus nubicolus, from Taylor (2013).


Now, I was not the first person to observe this point. Axel Schönhofer (2008) had already provided some detailed examples of variation in males of Rhampsinitus cf. leighi. I did, however, observe that the variation was even greater than Axel seemed to have recognised. Some of the least developed males of the species I was looking at had chelicerae that were pretty much no more developed than those of females. In some ways, the variation was even more remarkable than what I was familiar with in neopilionids. In most of the latter, major and minor males tend to be pretty similar to each other in features other than cheliceral development. In Rhampsinitus, we can see variation in almost all the features related to sexual dimorphism. In the species pictured immediately above, R. nubicolus, major males have massively long pedipalps as well as the long chelicerae; minor males have short, stubby pedipalps like those of a female. We can tell that they are the same species because they are found in the same location and have matching genitalia, but on the outside you would be hard pressed to pick them as such. Just to confuse matters even more, major males of two species may look very different to each other whereas minor males are externally almost identical. Without looking at the genitalia, it is all but impossible to identify which species a minor male belongs to.

As with the neopilionids, we can't yet say for sure what this variation means for the species' behaviour. In many other animal species with comparably varying males, large males will fight to protect and contain females while small males adopt a sneaking behaviour and try to spot females that are not being watched by large males. It seems quite possible that a similar thing is going on with Rhampsinitus. If you're a keen natural historian or behavioralist, there's something here that is crying to be looked into.

REFERENCE

Schönhofer, A. L. 2008. On harvestmen from the Soutpansberg, South Africa, with description of a new species of Monomontia (Arachnida: Opiliones). African Invertebrates 49 (2): 109–126.

New Zealand Harvestmen: Please Help

The cave-dwelling Forsteropsalis photophaga, a remarkable harvestman species described in Taylor & Probert (2014).


As regular readers of this blog will be well aware, I've been working for several years now, off and on, on the taxonomy of long-legged harvestmen of the family Neopilionidae from Australia and New Zealand. In the past few years, this has been a bit more off than on: the necessities of earning a crust have meant that I haven't had the time to dedicate to full-time harvestman research. Nevertheless, I've been putting things together here and there where I can and an enormous amount of progress has been made. Back when I first decided to investigate this group of animals in 2000/2001, there were a handful of named species, often with descriptions amounting to nothing more than a couple of vague lines, all but unidentifiable in practice. Over time, I've redescribed each of these species in turn, as well as describing and naming a pile of new ones. We've learnt things about these animals we never knew before, such as the presence in many populations of a remarkable divergence within males to the extent that to the uninitiated they might be (and have been) mistaken for completely different species. We've seen the incredible range of forms in this group, from long-jawed monsters like to one at the top of this post, to heavily armoured cryptic soil-dwellers like in this photo by Stephen Thorpe.

After many years, I feel I'm finally approaching the point where I can put the finishing touches on my revision of the New Zealand neopilionids (for a given value of 'finish', of course, because there is no group of organisms for which the work is ever truly finished). Ideally, I would like to publish something incorporating a complete overview of this group of animals, a complete guide to all the known species offering a one-stop-shop to allow anyone, anywhere to confidently identify any specimen that might come to their hand. It's also important to me that I publish this guide in an open-access format so that it's also available at any time.

But to do that, I need your help. In order to be able to travel to the New Zealand museums that hold types and other crucial specimens that I need to examine, and to cover the publication fees of the resulting product, I've started a crowdfunding drive. Head over to https://experiment.com/projects/how-can-we-distinguish-species-of-new-zealand-harvestmen and you'll be able to support my research, follow the results as they become available, and receive full acknowledgement in the resulting publication(s). Even if you can't support me directly myself, you would be helping immensely if you inform others of my campaign, whether through social media, in person, or any other medium that makes itself available. Together, we can bring this truly incredible group of animals the recognition they so richly deserve!

If you want to see some of my work on harvestmen that's already come out, check out the links below:

Remarkable things
Possibly the coolest thing I had published this year
Score one for biogeography
How to wipe out a family
The saga of Forsteropsalis fabulosa
More on the New Zealand Opiliones
Bye, bye, Spinicrus
The eater of light
New Zealand fills a biogeographical gap

New Zealand Fills a Biogeographical Gap

Lateral view of the holotype (and only known specimen) of new species Americovibone remota.


Taylor, C. K. 2016. First record of a representative of Ballarrinae (Opiliones: Neopilionidae), Americovibone remota sp. nov., from New Zealand. Journal of Arachnology 44 (2): 194–198.

New paper, and new species of phalangioid harvestman, out! And one that I'm pretty excited by, even if the vagaries of time allocation mean that I haven't been able to get the post out until a couple of weeks after it happened. After several years of studying New Zealand's long-legged harvestman fauna, I have to confess I was getting a bit complacent about. I certainly knew that I had not seen every species that the country had to offer, but I still thought that there were no real surprises remaining. The overall outline had become clear; any species of long-legged harvestman remaining to be described from New Zealand would be fairly closely akin to those already known.

Oh boy, was I wrong.

At some point last year (or maybe the year before), I was sorting through a jarful of specimens that were still waiting on my attention. In one of the vials, its contents collected in a remote part of the south-west South Island, was a tiny, wispy specimen that I at first glance paid little mind to. Newly-hatched juveniles are not uncommonly collected; they are almost always unidentifiable and end up being just chucked back into the jar never to be looked at again. Nevertheless, I pulled the specimen out to confirm that my first impression was correct. I placed the specimen in a dish under the microscope and glanced through the eyepiece. Then looked again, my eyes doubtless boggling. I may have even sworn a little. Not only was the specimen not a juvenile but fully adult, it was something I had long given up on seeing from New Zealand: a ballarrine.

Dorsal view of the main body.


The Ballarrinae are an unusual group of harvestmen that were not recognised until fairly recently. The group was named by Hunt & Cokendolpher in 1991 with species found in South Africa, Australia and South America. The South African species Vibone vetusta was the only one described prior to Hunt & Cokendolpher's (1991) paper, and until now no further species had been described since. The main reason these animals were overlooked previously is probably their size: ballarrines include some of the smallest of all harvestmen (the specimen I was looking at, for instance, has a central body only a bit over a millimetre long). Ballarrines differ from other harvestmen in the form of their pedipalps which are relatively long and have the patella much longer than the tibia (the converse is usually the case). Whereas other phalangioid harvestmen have the patella and tibia of the pedipalp more or less in a straight line or have the tibia bent slightly downwards, Hunt & Cokendolpher (1991) were struck by how the ballarrines had the tibia reflexed upwards relative to the patella. Ballarrine pedipalps also lack a terminal claw, and have only a relatively few glandular hairs instead of the denser covering of simple hairs found in other harvestmen. As noted in an earlier post and paper that I was associated with (Wolff et al. 2016), the overall pedipalp form is adapted for preying on small animals such as springtails: the long pedipalp acts like a tentacle that can be whipped forward to trap prey with its sticky hairs.

Until this point, New Zealand had been a puzzling gap in the Ballarrinae's otherwise classic Gondwanan distribution (long-term readers may recall that this is the second time I've seen a puzzling biogeographical lacuna filled). I didn't have any idea why that should be absent but even after looking at probably thousands of harvestmen specimens from all corners of the country I still hadn't seen any. Hence my immediate excitement about the find, but said excitement was also leavened with a certain degree of caution. Harvestmen taxonomy is heavily dependent on features of the males (particularly the male genitalia) with females of closely related species often being indistinguishable. Unfortunately, the only specimen of New Zealand ballarrine I had on hand was female. Sorting through the remainder of the collection I was working on failed to turn up any more. I even considered whether I could wrangle a trip to the original collection locality to see if I could find more specimens, but that proved unfeasible. The ballarrine had been collected by J. Dugdale in 1980 at a spot called the Dart Hut, which lies at the summit of the Rees-Dart walking track in Mount Aspiring National Park. This is a pretty isolated part of the country with no permanent population and no nearby roads. Travelling to the Dart Hut by foot takes a minimum of two days each way; the usual time taken to travel the Rees-Dart is five days (its supposed to be a nice hike that travels through similar terrain to the more famous Milford Trail without the massive crowds of the latter). What is more, at the time I was looking into it, the Rees-Dart was closed until further notice due to flooding earlier in the year taking out one of the bridges along it. Nevertheless, I eventually decided that the value of publicising the presence of this significant group in New Zealand outweighed the risk of not yet being able to confirm male morphology. Unfortunately, the nature of the specimen (spindly legs everywhere!) meant that I found myself unable to get good photographs and the resulting paper had to be illustrated with (always somewhat ropey when I do them) hand-drawn illustrations; nevertheless, the best photos I got are here in this post.

The tentacle-y pedipalp of A. remota is considerably longer than the central body; it's nearly as long as one of the legs!


Fortunately, sexual dimorphism within ballarrines tends to be low. I was very interested to see that the New Zealand ballarrine was more similar to the South American species Americovibone lanfrancoae than to any of the Australian species; so much so, in fact, that I ended up assigning it to the same genus as Americovibone remota. Americovibone lanfrancoae is also a very rare species, being described from only two known specimens from the Tierra del Fuego region. The most obvious difference between A. remota and A. lanfrancoae is that, in the former, the tibia of the pedipalp is not reflexed back above the patella as in every other ballarrine but is bent slightly downwards in a more standard position for phalangioids. This has some very interesting implications for ballarrine phylogeny. A molecular phylogenetic study of long-legged harvestmen by Groh & Giribet (2014) that included two ballarrines (the South African Vibone vetusta and the Australian Ballarra longipalpis) failed to unite the two as a clade. If accurate, this result would require the distinctive ballarrine pedipalp to have evolved on more than one occasion. The observation that A. remota may retain a more plesiomorphic pedipalp morphology could provide some correlation for this possibility.

But if Ballarrinae are indeed present in New Zealand, why are they apparently so rare? Part of the reason may be to do with habitat. Both the New Zealand and South American species of Americovibone are known from forests dominated by Nothofagus, southern beech. This tree genus is widespread in upland and colder parts of New Zealand. A bit north of the collection locality for A. remota, however, is an area where the beech forests disappear for a distance of a couple of hundred kilometres: this has been referred to as the "Nothofagus gap". Studies on other groups of organisms show that this gap is a significant one for New Zealand biogeography, with many beech-associated species restricted to one side or the other of the gap. Could A. remota be a specialist of the south-west beech forests of the South Island? If so, it is unique to one of New Zealand's least known corners.

REFERENCES

Hunt, G. S., & J. C. Cokendolpher. 1991. Ballarrinae, a new subfamily of harvestmen from the Southern Hemisphere. Records of the Australian Museum 43: 131–169.

Wolff, J. O., A. L. Schönhofer, J. Martens, H. Wijnhoven, C. K. Taylor & S. N. Gorb. 2016. The evolution of pedipalps and glandular hairs as predatory devices in harvestmen (Arachnida, Opiliones). Zoological Journal of the Linnean Society 177 (3): 558–601.

Harvestmen and their Hairy Pedipalps

A selection of harvestmen, showing a variety of pedipalpal morphologies, from Wolff et al. (in press). The upper two are Laniatores with spiny pedipalps; the lower two are Palpatores with leg-like pedipalps.


Wolff, J. O., A. L. Schönhofer, J. Martens, H. Wijnhoven, C. K. Taylor & S. N. Gorb (in press) The evolution of pedipalps and glandular hairs as predatory devices in harvestmen (Arachnida, Opiliones). Zoological Journal of the Linnean Society.

I'm happy to say that a new paper on which I am an author has just been made available. It's been a while (long-term unemployment has not profited my publication record, I must admit), but there are a few things still bubbling below the surface. This last entry is a study of the evolution of harvestmen's pedipalps, the more-or-less leg-like appendages on either side of the mouth that they use for collecting, capturing and manipulating food, and particularly the sticky hairs that many harvestmen have on them. My part in this publication was fairly minimal: I provided specimens and data on Neopilionidae, and assisted with the English-language composition. Full credit goes to my co-authors, particularly our lead author Jonas Wolff who drove it all.

I've learnt some interesting things myself working on this paper. When I first started researching harvestmen, most of the sources I read described them as scavengers, content to get by on decaying remains that they chanced upon in their wanderings. For some harvestman species, that is indeed their chosen diet. But some other species are not content with mere leavings, preferring their meat fresh and wriggling. These species are active predators, using their pedipalps to seize springtails and other small invertebrates. As a result of their use for this and other activities, harvestmen pedipalps show a wide range of shapes and sizes: some simple and presumably multi-purpose, others strikingly modified. Many species (particularly within the Laniatores, or 'short-legged' harvestmen) carry long spines on the pedipalps, and one might presume these to be the more blood-thirsty harvestmen. But, as reported by Wolff et al., there are many species no less active in their hunting (if not even more so) that not only have their pedipalps unadorned with spines but have even lost or reduced the claws that usually tip the pedipalps. What is going on here?

The answer lies in these species' possession of an alternative to spines: glandular setae. These are little hairs attached to a gland secreting a sticky glue that sits in a globule on a cluster of micro-hairs at the end of the seta, and are found in various species of the Palpatores ('long-legged' harvestmen). In some species the micro-hairs may be on one side, like a tooth- or a boot-brush; in others they may form a ring around the end. Using glue to capture prey can be even more effective than using spines or claws: springtails and such are often covered with scales or other loose structures that can slide off when the animal is seized, allowing the prey to escape and leaving the would-be predator with a handful of dust. Attacking the prey with multiple points of sticky glue, however, increases the chance of holding onto it, as the glue works around the scales and adheres to the body.

Two harvestmen showing convergent 'tentacle' pedipalps, the dyspnoan Mitostoma chrysomelas on the left and the ballarrine Ballarra longipalpis on the right, from Wolff et al. (in press).


Most harvestmen have not gone the whole hog for glandular setae; there is presumably scope for compromise with the use of the pedipalps for other purposes such as mating (the genital opening for harvestmen is around the mid-point of the underside of the body, so harvestmen mate 'face-to-face' and may use the pedipalps to hold onto each other). Many Palpatores possess a smattering of glandular setae at certain points on the inner side of the pedipalps only, and otherwise have a fairly underived leg-like pedipalp with a well-developed claw. One particularly interesting example that I hadn't heard of before was the Asian species Metagagrella minax, which possesses glandular setae as a juvenile but progressively loses them as it matures. Nevertheless, there are two groups, the Dyspnoi and Ballarrinae, that possess what Wolff et al. dub the 'tentacle' form of pedipalp: the pedipalps are elongate with glandular setae along the entire length and lack the claw entirely. The Dyspnoi is a purely Northern Hemisphere lineage, whereas the Ballarrinae are restricted to the Southern Hemisphere. The two groups sit nested on opposite sides of the primary divide within Palpatores, so there is no question that the 'tentacle' pedipalp has evolved independently in the two groups (which is also reflected by differences in each in the relative proportions of the segments making up the pedipalp). However, there is a bit of a question about whether the 'tentacle' has appeared even more often: Wolff et al. assume a single origin of the Ballarrinae but this has recently been cast into doubt. This is a question that interests me directly because of something else I've currently got on the boil... but that's a topic for another day.

The Eater of Light

The Waitomo harvestman Forsteropsalis photophaga, from Taylor & Probert (2014).


A little less than a year ago, I was contacted by a student at the University of Auckland in New Zealand, asking me about some harvestmen that she'd been trying to identify me from the Waitomo cave system. This incited a certain degree of excitement on my part, because I was not entirely unfamiliar with Waitomo's harvestmen. I had first seen specimens from there while doing my MSc back in 2001 or 2002, and had realised then that they represented an undescribed species. However, for various reasons, I had not yet published a description of the species in question. So when Anna contacted me, I decided it was time to bump the Waitomo harvestmen up the to-do list, and I replied to her asking if she would be interested in collaborating on a paper on the Waitomo harvestmen. She agreed, and the resulting paper came out just last week: C. K. Taylor & A. Probert, "Two new species of harvestmen (Opiliones, Eupnoi, Neopilionidae) from Waitomo, New Zealand".

Image of Waitomo cave, from here.


The Waitomo caves may be the world's only tourist attraction centred around an infestation of flies. The caves are home to an abundant population of glow-worms, larvae of the fungus gnat Arachnocampa luminosa. These fly larvae live on the roof of the cave, held in place by a silken hammock, and produce spots of brilliant blue light. It is the spectacle of these lights that draw the tourists, but for the glow-worms they serve a different purpose: the lights attract insects flying in the cave. In flying towards the light, insects become entangled in sticky threads that each glow-worm suspends below its hammock, providing the glow-worm with food. You can see a video of the process here, taken from the BBC's Planet Earth series.

But the glow-worms are not without predators of their own. With their long slender legs, harvestmen are able to carefully tip-toe between the sticky threads and pluck out the glow-worms, as from a luminous buffet (they also eat them at the pupal and adult stages). The harvestmen of Waitomo were studied by Myer-Rochow & Liddle (1988), who identified two species. One, a 'short-legged harvestman' Hendea myersi cavernicola (which actually has decidedly long legs, natch), is endemic to the cave system and was identified by Meyer-Rochow and Liddle as a strict troglobite (i.e. it spends its entire life within the cave). It has a number of features commonly associated with cave-dwelling, such as pale coloration and lengthened legs. It does differ from most troglobites in that it is not blind: while its eyesight is dim, it does retain enough to find its glowing prey.

Meyer-Rochow and Liddle also identified a 'long-legged harvestman' in the Waitomo caves, which they referred to as 'Megalopsalis tumida'. This name refers to a species first described from Wellington, quite some distance to the south, that now goes by the name of Forsteropsalis fabulosa (and has made an earlier appearance at this site, where it was the subject of this post). As it turns out, I identified two species of Forsteropsalis in material from the caves, neither of which was F. fabulosa. I can't be certain which was the species being looked at by Meyer-Rochow and Liddle. For various reasons, I suspect that they may have been looking at examples of both, but, as I've never been able to locate any vouchers for their study, I can't really say (remember, kids, vouchers are important).

Forsteropsalis bona, from Taylor & Probert (2014).


One of these species is indeed very similar to Forsteropsalis fabulosa, and has accordingly been labelled Forsteropsalis bona. Indeed, the two species are similar enough that I can now see that the photograph I used in my earlier post to illustrate F. fabulosa in fact shows an individual of F. bona. The primary difference between the two is in their pedipalps: in F. fabulosa, the patella of the pedipalp has a distinct finger-like process that is much reduced in F. bona. Forsteropsalis bona is not a strict troglobite: specimens have been collected at Waitomo both inside and outside the cave entrance. Instead, it is what is called a troglophile: individuals of F. bona probably use the caves as a cool, damp place to hang out during the day, emerging to forage outside the cave at night. This is the same pattern of behaviour found in New Zealand's cave wetas.

The second species is the beauty pictured at the top of this post. Its species name, photophaga, means 'eater of light', referring of course to its probable predation on glow-worms. This is a stunning animal: the enormous chelicerae typical of New Zealand Neopilionidae are rendered even more eye-catching by the presence of rows of longer spines (offhand, we don't yet know what the females of either of the Waitomo species look like, but they probably resemble other Forsteropsalis females in lacking the long chelicerae of the males). Whether Forsteropsalis photophaga is a troglobite or a troglophile is a bit more uncertain. I'm not aware of it having ever been collected outside the caves, but it doesn't seem to have the obvious modifications for cave-dwelling of Hendea myersi cavernicola (though when t comes to assessing elongated limbs in what is already a long-legged harvestman... how are you going to tell?). At present, I'm guessing troglophile rather than troglobite, but future studies may easily prove me wrong.

Forsteropsalis photophaga is also an intriguing animal from a taxonomic viewpoint. In the past, the two New Zealand harvestman genera Pantopsalis and Forsteropsalis have been pretty easy to distinguish, but F. photophaga has some features that are more reminiscent of Pantopsalis than of Forsteropsalis. Recently, other things have been brought to my attention that suggest that, while Pantopsalis as we currently know it still seems fairly robust, Forsteropsalis is beginning to look decidedly fuzzy around the edges. The relationship between these two genera (if, indeed, they should still be recognised as two separate genera) has still not been resolutely ironed out.

REFERENCE

Meyer-Rochow, V. B., & A. R. Liddle. 1988. Structure and function of the eyes of two species of opilionid from New Zealand glow-worm caves (Megalopsalis tumida: Palpatores, and Hendea myersi cavernicola: Laniatores). Proceedings of the Royal Society of London Series B (Biological Sciences) 233: 293–319.

There's No Such Thing as Caddids

Caddo agilis, from here.


Long-time readers of this site may recall my previous rants on the subject of the prolific, but not entirely reliable, arachnologist Carl-Friedrich Roewer. Hopefully, this post will serve to rehabilitate Roewer's image a little, because occasionally something comes along about which he was right in the first place.

Among Roewer's innovations in Die Weberknechte der Erde, his 1923 revision of the world Opiliones fauna, was the introduction of a new family for Acropsopilio, an odd little harvestman from South America. He placed this new family in the Dyspnoi, a subgroup of the Palpatores (long-legged harvestmen) that is otherwise found in Eurasia and North America. Acropsopilio was a distinctive beast, a tiny harvestman with relatively massive eyes (just take a look at the picture below!) Over time, other authors added to the Acropsopilionidae: species are now known from Australia, New Zealand and South Africa. They are nowhere comon, though.

Specimen of Acropsopilio neozelandiae, photographed by Stephen Thorpe.


In 1975, the acropsopilionids were revised by Shear (1975), who proposed that they were related to Caddo, a genus of harvestmen found in north-eastern Asian and north-eastern North America. That's not a typo, by the way: the range of this genus includes Japan and New England, but not the spaces in between. To make things just that extra bit wierder, the genus includes two species, C. agilis and C. pepperella, both of which are found in both the sections of its overall range. Genetic analysis has demonstrated that this wierdness is real, and not just convergence or one variable species (Shultz & Regier 2009). Caddo had previously been classed as a member of the Eupnoi, the other main subgroup within the Palpatores, but resembled acropsopilionids in features such as the small size and large eyemound. Shear proposed classing them all as a single family, Caddidae, with two subfamilies: one for Caddo and one for the Acropsopilioninae. Subsequent authors have followed his lead, and the Caddidae has come to be placed within the Eupnoi as the sister taxon to the Phalangioidea (the group including the familiar long-legged harvestmen such as the field harvestman Phalangium opilio).

Nevertheless, there was still a bit of humming and hawing going on behind the scenes. Despite the overall similarities in habitus between Caddo and acropsopilionines, several of the finer details (such as the structure of the pedipalps and genitalia) were quite different. Phylogenetic studies commenting on the position of caddoids within the Opiliones had generally included Caddo only, and not included any representatives of the acropsopilionines. And so it is quite welcome to see a new publication by Groh & Giribet (in press) in which they produced a molecular phylogenetic analysis of the caddids as a whole. The result, as hinted in the first paragraph, is that the caddids are not supported as a monophyletic group. Caddo remains in its accustomed position within the Eupnoi, but the acropsopilionids are placed as the sister clade to the Dyspnoi. Roewer, it turns out, had them in the right place to begin with.

This has some interesting implications: for instance, the otherwise entirely Holarctic Dyspnoi have just acquired a Gondwanan basal group. Also, the large eyemound is either a convergent feature between Caddo and acropsopilionines, or a retained primitive feature from the palpatorean common ancestor. Groh & Giribet suggest the latter, but I suspect the former to be just as likely (it may be related to small size: some phalangioids, such as the Mediterranean Platybuninae and the Western Australian Megalopsalis tanisphyros, also have large-ish eyemounds). But the greatest surprise for yours truly was something else: one particular 'acropsopilionine' genus, Hesperopilio, was not placed either with Caddo or the other acropsopilionines. Instead, it was placed closer to the the phalangioid family Neopilionidae: the subject of my own research.

When I produced my revision of the Australasian phalangioid family Monoscutidae (which I ended up synonymising with Neopilionidae), I included Caddo as an outgroup taxon in my morphological phylogenetic analysis. At the time, my supervisor asked me why I didn't include an acropsopilionine as well, but I demurred on two points. One was that, as rare as acropsopilionines were in collections, males were even rarer (there is evidence that they are commonly parthenogenetic, as for that matter is Caddo). The other was that acropsopilionine genitalia were truly bizarre, and I couldn't determine which parts of the acropsopilionine penis corresponded to where on the monoscutid organ.

I was basing that judgment on Acropsopilio and the South African genus Caddella (offhand, there is a longstanding tradition in harvestman taxonomy that whenever the name Caddella appears in a paper, it must be mis-spelled at least once). I still stand by that judgment. But upon seeing the results of Groh and Giribet's molecular analysis, I looked up the description of Hesperopilio (Shear 1996), which includes a drawing of the male genitalia. And suddenly, I was struck by the possibility that they could indeed be neopilionid-like. So I tried entering Hesperopilio into my original data set using the published descriptions. The result? Though missing a fair amount of data (my coding would need to be checked against actual specimens), a rough run suggests that morphology supports Hesperopilio as a neopilionid too!

The simplified version of what I end up with. Remember, this is by no means a thoroughly vetted result; this is just me going "what if I do this?"


So let that be a lesson, I suppose. Because of the belief that Hesperopilio was an acropsopilionine, I had never even considered taking a closer look at it. As it turns out, I really should have!

REFERENCES

Groh, S., & G. Giribet (in press) Polyphyly of Caddoidea, reinstatement of the family Acropsopilionidae in Dyspnoi, and a revised classification system of Palpatores (Arachnida, Opiliones). Cladistics.

Shear, W. A. 1975. The opilionid family Caddidae in North America, with notes on species from other regions (Opiliones, Palpatores, Caddoidea). Journal of Arachnology 2: 65–88.

Shear, W.A. 1996. Hesperopilio mainae, a new genus and species of harvestman from Western Australia (Opiliones: Caddidae: Acropsopilioninae). Records of the Western Australian Museum 17: 455–460.

Shultz, J. W., & J. C. Regier. 2009. Caddo agilis and C. pepperella (Opiliones, Caddidae) diverged phylogenetically before acquiring their disjunct, sympatric distributions in Japan and North America. Journal of Arachnology 37: 238–240.

Bye, Bye, Spinicrus

Female Spinicrus...no, sorry, Megalopsalis nigricans, photographed by Tony.


I've just had a paper out. The funny thing is, it's making me feel both pleased yet a little maudlin, because it represents something of an end of an era. The last part of my PhD thesis has been published. The last remnant of my student days has been cast off. I think I need a hug.

The paper in question is: Taylor, C. K. 2013. Further revision of the genus Megalopsalis (Opiliones, Neopilionidae), with the description of seven new species. ZooKeys 328: 59-117. It's open access, so go take a squizz. One thing that I also can't resist pointing out, though I don't know if it really makes much difference because it's a primarily online journal and hardly anyone will see the print issue: it's one of my images on the cover.

Technically, this paper represents my long-awaited (by me, at least) revision of the harvestman genus Spinicrus. In the end, though, I had to change the title of the paper, because on of the main results of this revision was that Spinicrus became a synonym of the older genus Megalopsalis. In an earlier publication, I cut Megalopsalis down to size by removing its New Zealand species to a new genus, Forsteropsalis. But now it's back, and stronger than ever before!
Female Megalopsalis tasmanica, the erstwhile Spinicrus tasmanicum. Another photograph from Tony.


Previously, Spinicrus was primarily separated from Megalopsalis by one feature: the presence of a side branch on one of the segments of the pedipalps of Megalopsalis. Taxonomists tend to be wary of defining a group purely by the absence of features. It implies that the members of that group are united more by the idea that they just don't belong in any other group, rather than anything that actually connects them per se. So, in this case, Megalopsalis was the species with a pedipalp side-branch, and Spinicrus was... the rest. It also didn't help matters that a pedipalp side-branch is something that has evolved and de-evolved a number of times within harvestmen, leading to a bit of questioning about its significance. A few years ago, I separated a few of the more distinctive 'Spinicrus' as the genus Neopantopsalis. This made Spinicrus a bit less heterogeneous but still didn't solve the underlying issue. It just meant that now you took out Megalopsalis and took out Neopantopsalis, and Spinicrus was still... the rest.

The answer, as so often in invertebrate taxonomy, came largely from the boy bits. When I looked at the male genitalia, I found that Megalopsalis and Spinicrus species shared a similar penis morphology, in which the end of the penis was fairly short, flat and shaped more or less like a rounded triangle:
This is what a 'Spinicrus' stewarti penis looks like.

In contrast, the end of the penis in Neopantopsalis species is longer, as demonstrated by N. thaumatopoios:

Put these features into a phylogeny of the family that these genera belong to (Neopilionidae), and I overall ended up with this:
Consensus of various phylogenetic analyses under various parameters (numbers at nodes represent the percentage of analyses in which that clade was recovered). Taxa coloured green are what would have been called 'Spinicrus' previously, while those in red would have been 'Megalopsalis'.


Note that this is a bit of a faux phylogeny, because it's a comparative summary of separate analyses under separate parameters (see the paper for details). Only those clades marked with a 100 were supported in all analyses. The important detail is the distribution of the green 'Spinicrus' relative to the red 'Megalopsalis': no matter what the analytical conditions, 'Megalopsalis' was always nested well within 'Spinicrus'. Indeed, under most conditions, 'Megalopsalis' was polyphyletic within 'Spinicrus'. Because of this, and because of the lack of any positive uniting features for Spinicrus species that were not also present in Megalopsalis, I felt the best course of action was to declare the two genera synonyms. Also subsumed under Megalopsalis was Hypomegalopsalis, a species that I had earlier established for a single species of uncertain affinities (Megalopsalis tanisphyros in the tree above). At the time, I commented that, "if anyone conducts a further study in the future that supports quashing Hypomegalopsalis, I won't be protesting". The fact that I got to do that myself just makes me all the happier.

There's a lot more I could talk about here, but I'm sure you all stopped reading long ago. Just go to the paper.

The Legacy of Rhampsinitus

According to the Histories of Herodotus, Rhampsinitus was a pharaoh of Egypt who ordered the construction of a secure storehouse for his wealth. However, the architect in charge of the storehouse's construction installed a secret entrance into it without the pharaoh's knowledge. The architect later told his two sons about the secret entrance, which they then used to help themselves to a share of the pharaoh's treasure. Unable to detect how the thieves were getting in, Rhampsinitus ordered a man-trap to be placed inside the storehouse, and the next time the thieves got in, one of them was caught by the trap. As there was no chance of escape, the remaining thief cut off his brother's head to prevent identification. Nevertheless, Rhampsinitus held onto the headless body and ordered his soldier's to look out for anyone showing signs of recent bereavement.

Through a ruse involving a pair of donkeys, a cartload of wine and some arguably irresponsible guards, the thief was able to recover his brother's body from the pharaoh, escaping both capture and his mother's complaints about his brother's mistreatment. Rhampsinitus therefore came up with another scheme to catch the thief: he ordered his daughter to offer herself up in a brothel to whoever would tell her the greatest misdeed he had committed. The thief did indeed confess his crimes to the daughter, who was apparently just that enticing. But when she attempted to grab hold of him and call for the guards, he escaped by palming a hand cut from a body that he had hidden up her sleeve. When he was told how the thief had eluded him again, Rhampsinitus was so impressed by the man's audacity and cunning that he ordered him pardoned. When the man came forward, Rhampsinitus gave him his daughter for a wife.

Male Rhampsinitus hispidus, from Roewer (1923). This would appear to be a species that lives up to its name; others are not quite so flagrantly spinose.


Modern historians agree that Rhampsinitus probably never existed, at least not as he was portrayed by Herodotus (while the accusation that Herodotus was the 'father of lies' is more than a little unfair, it must be admitted that he was not always one to let a little thing like historical accuracy stand in the way of a good story). Nevertheless, his name lives on today in southern Africa: in 1879, the French arachnologist Eugene Simon gave the name Rhampsinitus to a genus of long-legged harvestmen. Simon did not give any explanation for his choice, and it is possible that there was no direct reason: many authors gave random classical names to genera. Alternatively, it may be that the crown of denticles on the eyemound of this genus inspired Simon to give it a suitably regal name.

The long-legged harvestman fauna of sub-Saharan Africa is dominated by members of the subfamily Phalangiinae, which largely have the region to themselves except a few relictual Neopilionidae restricted to the southernmost part of the continent. Rhampsinitus is currently the largest recognised genus of African phalangiines, with over forty species. The centre of diversity for the genus is in the southern region, but it extends north to Zaire, Uganda and Kenya (possibly to Somalia, though the assignment of the Somalian species to Rhampsinitus has been questioned—Staręga 2009). Rhampsinitus is one of a group of African phalangiines (including Guruia and Dacnopilio, but not Cristina) in which the males have enlarged chelicerae similar to those of Australasian 'monoscutids'*. In the absence of a formal phylogenetic study of the Phalangiinae, it remains an open question whether these large-chelicerate genera form a clade. Schönhofer (2008) looked briefly at variation in male chelicera length (which can be considerable) within one species, Rhampsinitus transvaalicus; his results suggest an allometric relationship between body size and chelicera length for this species at least.

*A few years back, I was sent a pile of 'monoscutids' from the California Academy of Sciences to identify. While they're still waiting for me in the cupboard (sorry, guys!), I could see when I unpacked them that many were in fact African phalangiines that had been misidentified due to this character.

Relationship between altitude and eyemound ornamentation, as illustrated by Kauri (1961).


A number of species in this genus have interesting distributions, often related to altitude. Thus, in South Africa, Rhampsinitus leighi is found in lowland habitat from sea level to 800 m, while R. transvaalicus inhabits montane forest above 1200 m (Staręga 2009). Kauri (1961) made a comparison of morphometrics and altitude in South African Rhampsinitus: montane species had much shorter legs relative to body size than the lowland R. leighi. There was also a difference in development of ornamentation: R. maculatus, collected at 10,000 feet above sea level, had the denticles on the eyemound reduced to mere spicules, in contrast to the ornate, almost antler-like outgrowths of R. leighi.

REFERENCES

Kauri, H. 1961. Opiliones. In: Hanström, B., P. Brinck & G. Rudebeck. South African Animal Life: Results of the Lund University Expedition in 1950–1951 vol. 8 pp. 9–197. Almqvist & Wiksell: Uppsala.

Schönhofer, A. L. 2008. On harvestmen from the Soutpansberg, South Africa, with description of a new species of Monomontia (Arachnida: Opiliones). African Invertebrates 49 (2): 109-126.

Staręga, W. 2009. Some southern African species of the genus Rhampsinitus Simon (Opiliones: Phalangiidae). Zootaxa 1981: 43-56.

More on the New Zealand Opiliones

Male of Pantopsalis listeri, photographed by Simon Pollard, used with permission in Taylor (2013).


New paper published today! Hurrah! Except I've already had it pointed out to me that the species descriptions are missing the type depository, and one of the new species names has been mis-spelt in a couple of places. So I must shamefacedly prepare myself a correction...

The paper in question is titled 'Further notes on New Zealand Enantiobuninae (Opiliones, Neopilionidae), with the description of a new genus and two new species'. It's been published in ZooKeys, so it's freely available online at the link just given. As well as the two new species of harvestmen mentioned in the title, the paper also does something that I personally am even more pleased with: it manages to make two nomina dubia not dubia any more!

It started with my own private little eureka moment. A few months back, I was looking through some of the New Zealand harvestmen material that's been waiting for me to examine it. I pulled out one of the specimens and looked at it under the microscope. And as soon as I looked at it, I somehow had a thought pop into my mind: "That's Pantopsalis cheliferoides". Pantopsalis cheliferoides, I hasten to explain, is a species that was first described in 1882 by William Colenso, a missionary based in Ahuriri in Hawke's Bay. Colenso was a fascinating character, living with one hand firmly on the Bible and the other up a native girl's skirt (he was dismissed from the church in 1852 after fathering a child by his wife's maid, and not readmitted to its services until 1894). He produced the first book to be printed in New Zealand, and was the first to translate the Bible into Maori. He was also a keen natural historian, particularly interested in botany. His endeavours in zoology were perhaps a little less sure: when he collected the first specimens of P. cheliferoides, he doesn't seem to have been entirely sure if he was looking at a harvestman, a whip-spider, or a pseudoscorpion, so he kind of hedged his bets in giving it the name of Phalangium (Phrynus) cheliferoides. Unfortunately, P. cheliferoides then became something of a footnote in New Zealand arachnology. I had looked at the type specimen previously, but it wasn't enough for me to be sure of it's identity (and at the time, I was still a student and not confident enough to perform a genitalia dissection on a holotype). But it was enough that, when I came across more specimens of the species, I was able to recognise them for what they were. Hopefully, this will lift the animal that Colenso spent so much time trying to identify* out from its obscurity.

*In Colenso's own words: "I have only seen four specimens in the woods, throughout three years, although from my first seeing one in 1879 (which I failed to capture), I have sought most diligently for specimens. In the following year I accidentally, and most unexpectedly, saw another in the same forest, and though I tried long and arduously to secure it without smashing, I failed to do so; it spread out its long flexible legs so prodigiously, that in the end it escaped among the thick vegetation" (Colenso 1882).

Male Pantopsalis cheliferoides, from Taylor (2013).


The other nomen ex-dubium dealt with in the paper is arguably even more important, as it is the type species of the genus Pantopsalis. This species was first described as Phalangium listeri by A. White back in 1849, in about three lines of text that are completely inadequate to recognise the species in question (with no further locality data given than 'New Zealand'), and the type specimen(s) seem to have since been lost. The species was redescribed by the French arch-arachnologist Eugene Simon in 1879, who placed it in the new genus Pantopsalis. Recently, I was able to borrow Simon's P. listeri specimens from the Muséum national d’Histoire naturelle in Paris; as it turns out, they belong to the same species that I had dealt with in 2004 under the name of Pantopsalis luna. Because the original type was lost, I've designated one of the Paris specimens as the neotype for P. listeri. It isn't entirely certain that Simon was actually looking at the same species as White had been (indeed, as mentioned in the paper, there's some cause to believe he wasn't). But everyone since Simon has followed his lead on the identity of Pantopsalis, and naming one of his specimens as neotype has the advantage of confirming the status quo.

Male of Mangatangi parvum, from Taylor (2013).


The two new species in the paper are Forsteropsalis pureora (as it should have been throughout, dammit) and Mangatangi parvum. The latter species is particularly neat: it's very small compared to some of the other long-legged harvestmen in New Zealand, and certain features suggest that it may represent the sister taxon to the clade containing the genera Pantopsalis and Forsteropsalis. I'm still doing some work to try and test that.

REFERENCES

Colenso, W. 1882. On some newly-discovered New Zealand arachnids. Transactions and Proceedings of the New Zealand Institute 15: 165–73.