Studying taxonomic families on the campus of the University of Sucre

Autores: Betín Laura, Borja Jesús, Pérez Eliana.

Summary
Describing a plant morphologically involves observing all the characteristics.
visible or internal parts such as leaves, flowers, stems, and ovary respectively. Allowing the
differentiation of already classified taxa into families. In order to choose states of
character of the species belonging to certain families, for the correct elaboration of
a dichotomous key. For this, the collection was carried out on the university campus
Plant sugars belonging to 4 types of families (Araceae, Bromeliaceae, Arecaceae)
which were taken to the laboratory where a detailed description was made at the level
morphological, which led to a taxonomic classification of each specimen. Following
This, characters were selected from the species of these families and a key was developed.
dichotomous that addressed the unique characteristics of each family and the clear differentiation or
similarity between them.

Introduction
The description of a plant or group of plants (taxa) consists of a series of phrases of
its characteristics, so that they constitute a definition of a taxon.
The characters that contribute to a taxonomic description are known as the
characters taxonomic o systematic.
The diagnosis is a reduced description that covers only the diagnostic characteristics, which
they are necessary to distinguish a taxon from other related taxa (Olivares, 2007).
The methodological basis of plant individualization is the analytical key or tool of
identification. This descriptive literary element has been used for many
generations (Campbell, 2007).
The principle of making, as well as the correct use of a taxonomic key
It consists of dividing the studied group into two or more branches by means of searching for
contrasting or exclusive characters, which is why it requires
descriptions of a group of plants with a good identification to avoid mistakes
at the time of creating a key, in order to be able to differentiate them correctly between
families, as this corresponds to one of the taxonomic levels of the system of
classification created by Linnaeus to group individuals and that later was
revised and adapted according to the new knowledge that was being acquired (León,
2000). Therefore, for this practice, it was sought to choose states of the character of the species.
belonging to certain families, for the correct preparation of a dichotomous key.

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Methodology
The collection was made on the campus of the University of Sucre of plants belonging to 3
types of families (Araceae Bromeliaceae, Arecaceae) were taken to the laboratory where
a detailed description was made at the morphological level, which led us to a
taxonomic classification of each specimen. After this, characters were chosen
homologous among the species of these families and a dichotomous key was developed that
addressed the characteristics specific to each family.

Descriptions:
Araceae Family
Caladium bicolor
Herbaceous plant of terrestrial habitat, equipped with underground tubers (thickened stems),
up to 50 cm in height, with peltate leaves, from ovate to elliptical, 15 to 45 cm long and
width, respectively, with the base more or less sagitated or corded, whole margin;
petiole 5-25 cm long; they are green with various red or pink colorations
haz, and glaucous on the underside; primary veins are red. Inflorescence formed by
a spike of numerous small flowers arranged on a fleshy axis (spadix),
understood by a bract similar to a leaf or petal (spathe).

Aglaonema commutatum

Herbaceous plant of terrestrial habitat, ranging from 20 cm to 150 cm in height, has simple leaves.
alternating on the stems, lanceolate to narrowly oval, dark or medium green with 10-
45 cm in length and 10-16 cm in width, with a whole margin. Inflorescence in spathe and
cream-colored spadix.

Bromeliaceae Family:

Tillandsia ionantha
It is a type of epiphytic plant, stemless, with a size of 6-8 cm high, its leaves
simple leaves are approximately 4–9 cm long; with sheaths 0.6–1 cm
wide, these leaves are elongated and narrow especially at the tips, they are green in color
silver-colored especially at its base, they are flat and thick, and have tiny scales of
silver-gray color that stores water and reflects sunlight. Its inflorescence.
composed (of simple appearance due to the reduction of the spikes to 1 flower), contains 1–
3 flowers, has leafy primary bracts, much longer than the spines, bracts
flowers approximately 3 cm long, longer than the sepals and covering them in the
antesis, sessile flowers; sepals 2 cm long, free, the 2 posterior ones keeled, the
anterior ecarinado; erect-growing purple petals with yellow stamens
outstanding. Its capsule is approximately 2.5–4.5 cm long.

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Ananas ananassoides
It is a herb with basal branching (without bulbils or stolons), The plant can
to grow to a height of approximately 0.9 meters, the stem is almost acaulescent or
with a very short stem, trunk-shaped, at the base of the rosette. It has inflorescence
cylindrical 8 to 12 cm long. The mature fruit has the shape of a small tuft and is
slightly sweet and sour flavor.

Family Aracaceae
Royal Palm
Land tree. They are large palms with a grayish trunk at the bottom and green color.
at its top, it measures approximately 4 meters in height. The leaves of 1 meter are
composed of leaflets arranged in different planes with respect to the rachis, which is
arched; the leaves have a parallel camptodromous venation. Its flowers are colored
cream. Its fruit is bright red and attractive.
Bactris gineensis
It is a clump-forming palm with up to one hundred erect stems ranging from 3 to 5 m in height and 1.5 to 3 cm in diameter.
diameter. Its leaves are spirally arranged along the stem. The sheath is 30 to 60 cm long.
length has thin spikes 1 cm long. The petiole of 4 to 7 cm has thorns of
3 to 6 cm, also present in the rachis, which measures 25 to 80 cm in length and has 19
a 42 pins from 20 to 30 cm on each side. Flowers of 4 to 6 mm staminate and pistillate. The
The inflorescence support can be up to 20 cm long, with a yellowish bract on top.
It has bunch fruit, is globose and depressed, dark purple-black color, from 1.5 to 2 cm of
diameter (Ochoa, 1991)
Matrix
Family Araceae Bromeliaceae Rutaceae
Caladium Aglaonema Tillandsia Ananas Roystonea Bactris
bicolor changed ionantha ananassoides Regia gineensis

Epiphytic plant 0 0 1 0 0 0
Plant 1 1 0 1 1 1
terrestrial
Leaves 0 0 0 0 1 1
composed
Simple leaves 1 1 1 1 0 0
Stem 0 0 1 1 0 0
acaulescent
Stem 1 1 0 0 1 1
Cauleous
T. column 0 0 0 0 1 0
Herbs 1 1 1 1 0 0
Trees 0 0 0 0 1 1

3
 Stings 0 0 0 0 0 1
Thorns 0 0 0 1 0 0
Inflorescence 1 1 1 1 1 1
H. petiolated 0 1 0 0 1 1
H. 0 0 1 1 0 0
wrapping machines

Dichotomous Key:
1. Petiolate leaves
1. Sheathing leaves, stemless stalk, herbs with inflorescences
Bromeliaceae

2. Composite Leaves ________________________________ 3

3.Trees with inflorescence, woody stem with fleshy fruit _ _ _ _ _ _ _ _ _ _ _ _ _ _ Arecaceae

Bibliography

Olivares, A. (2007). Molecular Systematics. University of Santiago de Compostela.