Cephalotes persimilis

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Cephalotes persimilis
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Cephalotes
Species: C. persimilis
Binomial name
Cephalotes persimilis
De Andrade, 1999

Cephalotes persimilis casent0173700 profile 1.jpg

Cephalotes persimilis casent0173700 dorsal 1.jpg

Specimen labels

Besides the fact that specimens of this species was collected from scrubby riparian forest in Guyana, nothing is known about the biology of Cephalotes persimilis.

Identification

A member of the grandinosus clade differing from its sister species Cephalotes persimplex, in the worker and soldier by the body hairs longer and thinner, and, in the gyne, by the frontal carinae crenulate and with denser hairs and in the worker, soldier and gyne of C. persimilis having smaller and more regular foveae on the cephalic dorsum. The male of Cephalotes persimilis is almost of the same size of the gyne, a condition unique among all other known Cephalotes males so far and approaching the condition Procryptocerus where the males are regularly slightly larger than the gynes. The persimilis males exhibit another remarkable character: the inflated femora as they are known for males of the members of the laminatus and pusillus clades and for Procryptocerus. (de Andrade and Baroni Urbani 1999)

Keys including this Species

Distribution

Guyana, Brazil, Argentina and Paraguay.

Distribution based on Regional Taxon Lists

Neotropical Region: Argentina, Brazil (type locality), Paraguay.

Distribution based on AntMaps

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Distribution based on AntWeb specimens

Check data from AntWeb

Biology

The biology of many Cephalotes species is not known. Ants in this genus are common in the New World tropics and subtropics and are especially abundant and diverse in the canopies of Neotropical forests. The majority of species are arboreal. Species that live in other strata inhabit smaller trees, bushes or grass stems. These noon-arboreal species, due to their accessibility, are among the better studied members of the genus. There are also species that can be found in downed wood but it is likely the wood housed the colony before it fell to the ground. Soil nests are not known for any species nor do most species appear to extensively excavate plant tissue. They nest instead in preformed cavities. Overall, ants in the genus utilize a wide range of plants. Some species are predictable in their plant use but none appear to have evolved specialized mutualisms with particular plant species.

Worker castes typically include two forms, a worker and soldier, but there are a few species that are monomorphic. The larger soldier caste typically has an enlarged head disk. In some species the head of the soldier is very different from the worker while in others these differences are less pronounced. Queens and soldiers tend to share similar head morphology. Soldiers use their heads to plug the nest entrance. This can be very effective in excluding potential intruders. Other morphological differences between the worker castes are present but these differences have not been studied as well as head moprhology.

The behavioral repertoire of Cephalotes varians has been examined in great detail (ethograms from Wilson 1976, Cole 1980 and Cole 1983). Soldiers do little else besides defend the nest. This specialized soldier behavior is presumed to be the norm for most species. An especially interesting behavior occurs when workers are dislodged from trees: they "fly" towards the tree, often grabbing the trunk well above the ground (video).

Mature nest size varies, by species, from less than a hundred to many thousands of workers. Available evidence suggests most species are monogynous. Queens may mate with multiple males.

The proventriculus of the Cephalotes is peculiar relative to other ants. The morphology of the structure suggests it serves as a powerful pump and filter. This does not appear to lead these ants to have a highly specialized diet as most species appear to be general scavengers. Foragers have been observed feeding on carrion, bird feces, extrafloral nectaries and even tending membracids. Pollen feeding has been observed in some species, and this is somewhat specialized for ants, but it is not evident that any species restricts its diet to this resource in any significant way. Evidence for pollen feeding in Cephalotes has accumulated, in part, via finding digested pollen grains seen in infrabucal pellets. It has been suggested that the morphology of the proventriculus is a specialization for processing pollen.

More research examining all aspects of the biology of Cephalotes is needed. Our present understanding of these ants is largely based on species that live in locations other than the forest canopy, which is where Cephalotes are most common and diverse.

Castes

Nomenclature

The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.

  • persimilis. Cephalotes persimilis De Andrade, in De Andrade & Baroni Urbani, 1999: 441, figs. 201-204 (s.w.q.m.) BRAZIL.

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.

Description

Worker

Head subquadrate; frons gently convex. Frontal carinae covering the sides of the mandibles and slightly upturned above the eyes; border of the frontal carinae superficially crenulate. Vertexal angles membranaceous, with an obtuse margin converging and narrowing before the middle of the vertexal border. Mandibles with thick lateral carina.

Mesosoma gently convex. Scapular angles absent or not visible in dorsal view. Anterior pronotal border straight; pronotal sides with a broad, gently concave membranaceous expansion, anteriorly angulate and narrowing posteriorly. Promesonotal suture superficially impressed or absent. Mesonotum with two pairs of triangular, membranaceous teeth, the anterior pair longer, thicker and broader than the posterior one. Propodeal suture impressed. Declivous face of the propodeum gently sloping backwards. Basal and declivous propodeal faces with a broad membranaceous expansion starting from the anterior part of the basal face and strongly projected anteriorly, almost reaching the mesonotal spines forwards and broadening backwards.

Petiole with a concave anterior face laterally marked by a small pair of obtuse denticles; petiolar dorsum sloping anteriorly. Sides of the petiole with a broad, gently concave, wing-shaped, membranaceous expansion with round tip. Postpetiole slightly convex dorsally; postpetiolar sides with another broad, wing-shaped, membranaceous expansion with round tip.

Gaster and legs as in persimplex.

Sculpture. Head dorsum with dense, small foveae diminishing in size and less impressed anteriorly. Frontal carinae with faint, sparse, superficial foveae and with longitudinal rugosities. Ventral face of the head reticulate and with thin, superficial, longitudinal rugosities. Mesosoma with irregular foveae superimposed by longitudinal, irregular rugosities. Pedicel with the same type of sculpture as on the mesosoma but with smaller foveae. Gaster and legs strongly reticulate; thin, irregular, longitudinal rugosities on the anterior third of the first gastral tergite and on the legs. Membranaceous expansion of mesosoma, pedicel and gaster punctate and with thin, longitudinal rugosities.

Pilosity. Each fovea with a decumbent or an appressed hair; similar hairs but not originating from the foveae on the membranaceous expansions of the body. Legs and gaster with appressed hairs thinner and shorter than the hairs originating from the foveae. Frontal carinae anteriorly and over the eyes, and posterior part of the gastral segments with rare to sparse, clubbed hairs. The gastral sternites bear, in addition, a few long, thin, slightly pointed hairs.

Colour. Body light brown. Frontal carinae opaque, yellow. Membranaceous expansions whitish and semi-transparent. Tarsi brown.

Measurements (in mm) and indices: TL 3.52-4.56; HL 0.83-1.08; HW 0.95-1.24; EL 0.26-0.29; PW 0.87-1.16; PeW 0.56-0.76; PpW 0.55-0.76; HBaL 0.22-0.3 1 ; HBaW 0.09-0.15; CI 113.6-115.9; PI 105.6-107.4; PPeI 150.8-160.7; PPpI 149.2-163.6; HBaI 40.0-48.4.

Soldier

Head disc subquadrate, with the border differentiate, sparsely and superficially crenulate and raised on the sides only; sides of the disc parallel or broadening anteriorly, covering or not the eyes. Posterior border of the disc with a pair of small denticles. Floor of the disc gently convex in the middle. Vertexal angles obtuse to pointed, completely separate from the disc and with marked, crenulate border. Mandibles laterally carinate and laterally hidden by the frontal carinae.

Mesosoma. Anterior pronotal border gently convex. Humeral angles with a short or broad, obtuse, membranaceous expansion with straight sides posteriorly up to the middle of the pronotal sides where it continues into the pronotal carina. Posterior half of the pronotal sides strongly converging. Pronotal carina high, each half posteriorly convex and diminishing in height towards the middle of the pronotum. Pronotal suture impressed. Promesonotal suture deeply impressed. Mesonotal sides with a pair of broad, triangular, obtuse or pointed teeth followed by a pair of thin, pointed, membranaceous denticles. Propodeum with differentiate basal and declivous faces; sides of the basal face with a narrow, crenulate, membranaceous expansion, forming cranially a pair of obtuse teeth directed anteriorly and followed by a convexity converging posteriorly into a pair of small denticles. Declivous face of the propodeum narrowing posteriorly and with a broad, membranaceous expansion.

Pedicel and legs as in persimplex.

Gaster oval, with a pair of lobes protruding anteriorly and bearing narrow membranaceous expansions.

Sculpture. Head dorsum superficially punctate, slightly shining and with foveae with diameter smaller than their interspaces and diminishing in size anteriorly. Ventral face of the head punctate and with anastomosing, superficial foveae denser over the sides. Mesosoma and pedicel with the same type of sculpture as the posterior part of the head dorsum but with denser foveae, the foveae smaller on the propodeum and on the pedicel. Declivous face of the propodeum, gaster and legs reticulate; few longitudinal, thin rugae on the declivous face of the propodeum and on the anterior third of the first gastral segment. Center of the first gastral sternite superficially shining.

Pilosity. Each fovea with an appressed hair. Legs and gaster with appressed hairs thinner and shorter than the hairs originating from the foveae. Frontal carinae, vertexal angles, mesosoma, pedicel with sparse, clubbed hairs; similar hairs but shorter on the gaster. The sternites bear, in addition, a few long, thin, slightly pointed hairs.

Colour. As in the worker.

Measurements (in mm) and indices: TL 4.38-5.60; HL 1.04-1.28; HW 1.22-1.48; EL 0.27-0.32; PW 1.20-1.44; PeW 0.57-0.77; PpW 0.58-0.80; HBaL 0.22-0.33; HBaW 0.12-0.16; CI 115.5-121.4; PI 95.7-104.7; PPeI 185.5-217.5; PPpI 180.0-210.2; HBaI 40.9-48.5.

Queen

Head disc present. Head dorsum convex with gently concave anterolateral sides. Frontal carinae crenulate, expanded anteriorly, converging posteriorly and connected by a slightly convex carina on the vertex. Vertex with a superficial depression between the pair ocelli. Vertexal angles obtuse and with crenulate margin. Eyes visible in full dorsal view. Ocelli remote from the posterior border of the head disc. Anterior clypeal border concave. Mandibles with a lateral carina and partially hidden by the frontal carinae.

Mesosoma. Anterior pronotal border gently convex. Humeral angles with or without a pair of small, obtuse, membranaceous teeth converging posteriorly and connected with a narrow pronotal carina. Pronotal sides posterior to the angles straight. Promesonotal suture impressed. Lower mesopleurae with a denticle. Mesonotum and scutellum flat. Propodeum with differentiate basal and declivous faces; sides of the basal face convex and ending in a round tooth posteriorly; declivous face converging posteriorly and with a narrow membranaceous border on the posterior half.

Pedicel, gaster and legs as in pcrsimplex.

Sculpture. Head dorsum with dense, deep, round foveae diminishing in size anteriorly. Interspaces between the foveae minutely punctate and shining. Ventral part of the head and propleurae with superficial, irregular, anastomosing foveae, the foveae denser on the ventral sides of the head. Pronotum, propleurae, mesonotum and scutellum minutely reticulate and foveolate, the foveae sparser on the mesonotum and on the propleurae. Basal face of the propodeum, mesopleurae and pedicel superficially reticulate and with dense, small foveae, the foveae rare on the middle of the lower mesopleurae. Declivous face of the propodeum, metapleurae, gaster and legs reticulate; few longitudinal rugosities on the declivous face of the propodeum, on the upper and lower parts of the metapleurae and on the anterior third or anterior half of the first gastral tergite, the latter also with sparse piligerous foveae.

Pilosity. Each fovea with a decumbent or appressed hair. Legs and gaster with appressed hairs slightly thinner than the hairs originating from the foveae, sparser on the sternites. Prontal carinae wilh spars e, clubbed hairs. Gastral tergites and sternites with slightly clubbed, suberect hairs, denser on the sternites. The gastral sternites bear, in addition, a few long, thin, slightly pointed hairs.

Colour. Light brown. Frontal carinae yellowish-opaque. Tarsi brown. First gastral tergite with a pail: of dark brown maculae on the middle of the dorsum faintly connected medially in some specimens.

Measurements (in mm) and indices: TL 6.60-8.40; HL 1.16-1.56; HW 1.20-1.64; EL 0.32-0.37; PW 1.08-1.56; PeW 0.55-0.75; PpW 0.70-0.90; HBaL 0.40-0.50; HBaW 0.15-0.18; CI 101.3-105.9; PI 104.2-111.1; PPeI 196.4-226.7; PPpI 154.3-188.9; HBaI 34.1-40.0.

Male

Head (eyes included and mandibles excluded) 1/2 broader than long. Vertexal angles gently convex in d orsal view. Frontal carinae marginate or not, not surpassing the first ocellus and diverging posteriorly. Frons flat. Clypeus posteriorly convex and almost straight anteriorly. Mandibles strongly carinate. Scapes thick, twice longer than the first funicular joint; remaining funicular joints thickening from the base to the apex.

Mesosoma. Pronotal sides slightly diverging and carinate. Mesonotum and scutellum almost flat in side view; median Mayrian furrow superficially impressed. Propodeum slightly lower than the rest of the mesosoma, with differentiate basal and declivous faces; basal face and anterior part of the declivous face convex; propodeal sides each with a thin lateral carina converging posteriorly.

Pedicel convex and very broad. Petiole slightly narrower than the postpetiole and with concave anterior face; petiole and postpetiole arched laterally.

First gastral tergite almost twice as broad as the maximum postpetiolar width.

Legs with femora relatively inflated.

Sculpture. Head punctate, irregularly foveolate on the posterior fourth, with oblique rugosities on the vertexal angles, longitudinal between the ocelli until the frontal carinae, transversal in front of the eyes and between the scapes. Ventral part of the head punctate, irregularly foveolate-rugulose, the rugae oblique around the eyes and irregularly longitudinal on the middle. Pronotum, mesonotum and scutellum superficially and minutely reticulate, subopaque, sparsely and superficially foveolate and longitudinally rugose, the rugae generally thin, more impressed on the Mayrian furrows and on the scutellum. Propodeum minutely reticulate, shining or not, with thick longitudinal rugosities prolonging backwards. Pedicel minutely reticulate-punctate, superficially shining and completely covered by longitudinal rugosities. Pleurae moderately shining and longitudinally rugose, the rugae less impressed on the metapleurae and on one specimen on the lower part of the mesopleurae as well. Gaster and legs almost completely shining.

Pilosity. Body with long, flexuous hairs, sparser on the gaster and on the legs. Gaster and legs with additional hairs subdecumbent to decumbent, shorter than the flexuous ones. Funiculi densely covered by thin, short, decumbent hairs; similar hairs but thinner, sparser and slightly longer on the legs and on the gaster.

Colour. Black. Pedicel, gaster and legs brown.

Measurements (in mm) and indices: TL 6.00-6.84; HL 0.80-0.84; HW 1.04-1.08; EL 0.42-0.43; PW 1.00-1.20; PeW 0.65-0.71; PpW 0.72-0.77; HBaL 0.50-0.53; HBaW 0.11-0.13; CI 128.6-130.0; PI 90.0-104.0; PPeI 153.8-169.0; PPpI 138.9-155.8; HBaI 22.0-24.5.

Type Material

Holotype soldier, Tanquinho, Feira de Santana, Bahia, Brazil, 08.XII.1953, C. R. Goncalves Museu de Zoologia da Universidade de Sao Paulo; paratypes 1 worker, 1 soldier, same data as the holotype MZSP.

Etymology

From the Latin persimilis = very similar (Cicero), referred to the great similarity between this species and C. grandinosus.

References

  • de Andrade, M. L.; Baroni Urbani, C. 1999. Diversity and adaptation in the ant genus Cephalotes, past and present. Stuttgarter Beitrage zur Naturkunde Series B (Geolgie and Palaontologie). 271:1-889. (page 441, figs. 201-204 soldier, worker, queen, male described)