Cephalotes cordiventris

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Cephalotes cordiventris
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Cephalotes
Species: C. cordiventris
Binomial name
Cephalotes cordiventris
(Santschi, 1931)

Cephalotes cordiventris P casent0627939.jpg

Cephalotes cordiventris D casent0627939.jpg

Specimen Label

The report by Cornaby (1974) of unidentified Cephalotini feeding on carrion in Costa Rica refers to this species. Specimens have been collected in a number of wet/moist forest habitats.

Identification

A member of the basalis clade differing from its sister species Cephalotes mompox by the absence of striation on the posterior face of the femora. cordiventris may be easily differentiated from the similar Cephalotes basalis as follows: worker with narrower pronotal lamellae and first propodeal teeth angulate instead of pointed, soldier and gyne with reduced vertexal spines (instead of pointed denticles as in basalis). The limited material of gynes available (two for cordiventris and four of basalis) suggest important differences also in the size, position and colour of the gastral spots, as detailed in their respective descriptions. (de Andrade and Baroni Urbani 1999)

Keys including this Species

Distribution

Occurs in Costa Rica and Panama.

Distribution based on Regional Taxon Lists

Neotropical Region: Costa Rica, Panama (type locality).

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.

  • cordiventris. Cryptocerus (Paracryptocerus) multispinus var. cordiventris Santschi, 1931c: 274 (s.w.) PANAMA. De Andrade & Baroni Urbani, 1999: 263 (q.). Combination in Cephalotes: De Andrade & Baroni Urbani, 1999: 259. Junior synonym of multispinus: Kempf, 1951: 204. Revived from synonymy and raised to species: De Andrade & Baroni Urbani, 1999: 259.

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

Description

Worker

de Andrade and Baroni Urbani (1999) - Differing from mompox essentially in sculpture and little in morphology: small workers of cordiventris possess the pronotal lamellae less broad and converging posteriorly into a gently notched border, the propodeum less broad and the HBaI greater.

Sculpture. The reticulation and the foveae on the mesosoma are less dense than in mompox. Declivous face of the propodeum and legs minutely and superficially reticulate instead of longitudinally rugose.

Measurements (in mm) and indices: TL 6.32-7.44; HL 1.56-1.80; HW 1.88-2.28; EL 0.52-0.60; PW 1.78-2.24; PeW 1.20-1.48; PpW 1.12-1.28; HBaL 0.76-0.94; HBaW 0.27-0.32; CI 120.5-126.7; PI 101.9-105.9; PPeI 145.7-151.3; PPpI 158.9-175.0; HBaI 34.0-35.5.

Soldier

de Andrade and Baroni Urbani (1999) - Head subquadrate, convex and without disc. Vertexal angles obtuse. Vertex with a pair of small median teeth or simply a pair of swellings. Frontal carinae broad anteriorly, converging in front of the eyes and superficially marked behind the eyes. Mandibles broad, their sides with an impressed, round, carinate protuberance. Eyes almost flat.

Mesosoma. Anterior pronotal border convex. Pronotal sides with a pair of broad lamellae, pointed anteriorly, straight or gently convex medially and strongly converging posteriorly.

Pronotal carina thick, raised and interrupted medially by an impression. Promesonotal suture impressed. Mesonotal sides with a pair of broad spines with pointed or round tip. Propodeal suture deeply impressed. Propodeum with differentiate basal and declivous faces; basal face either straight anteriorly or gently diverging over the whole sides into a pair of broad, large, pointed or round teeth. These teeth are followed by a concavity and by another, larger pair of teeth with round tip; sides of the declivous face converging posteriorly.

Petiole. Anterior face truncate; posterior face sloping backwards and with a superficial, median, transversal carina. Petiolar sides diverging posteriorly and with a pair of broad, long, pointed spines curved upwards. Dorsum of the postpetiole gently convex. Postpetiolar spines thick, pointed and arising from the anterior side of the postpetiole.

Gaster round, slightly longer than the mesosoma; anterolateral border of the first gastral tergite with a lamella not surpassing the first gastral stigma posteriorly.

Legs. Fore coxae tumuliform anteriorly. Fore femora as broad as or slightly narrower than the hind ones. Mid and hind femora angulate medially; mid and hind basitarsi laterally compressed and with broad base.

Sculpture. Head, mesosoma and pedicel minutely punctate and covered by small, superficial foveae smaller than their interspaces, larger and denser on the lateral part of the propodeal dorsum, on the petiole and on the postpetiolar spines. Ventral face of the head and propleurae minutely punctate and with the same sculpture as on the propodeal sides or with broader and deeper foveae in some specimens only. Lower meso- and metapleurae, outer face of the distal part of the femora, tibiae and anterolateral fourth of the first gastral tergite with dense, oval foveae. Declivous face of the propodeum, remaining parts of the pleurae and of the legs minutely reticulate-punctate. First gastral tergite with minute, superficial reticulation and foveae in small specimens; the same sculpture but less impressed and very shining in large specimens. First gastral sternite reticulate on the sides and shining in the middle.

Pilosity. Each fovea bearing an appressed hair of size proportional to the size of the fovea. Legs and posterior border of the gastral segments with erect, slightly clavate hairs. First gastral tergite anterolaterally covered by a spot of appressed hairs.

Colour. Shining black. First gastral tergite anterolaterally with a whitish-golden macula made out of a tuft of dense hairs.

Measurements (in mm) and indices: TL 8.44-10.20; HL 2.24-2 .68; HW 2.56-3.08; EL 0.61-0.65; PW 2.56-3.04; PeW 1.52-2.00; PpW 1.32-1.68; HBaL 0.80-0.96; HBaW 0.30-0.36; CI 112.0-114.9; PI 100.0-101.3; PPeI 152.0-168.4; PPpI 180.9-193.9; HBal 36.9-37.5.

Queen

de Andrade and Baroni Urbani (1999) - Head as in the soldier, but with the frontal carinae less broad and the eyes more convex. Ocelli far from the vertexal margin.

Mesosoma moderately convex in profile. Pronotal sides with short, obtuse humeral angles. Pronotal carina absent or superficially impressed on the sides. Mesonotum flat in side view. Lower mesopleurae with a lateral tooth. Sides of the basal face of the propodeum with two pairs of teeth separate by a superficial concavity, the first pair broad and triangular, the second longer than the first and with obtuse or pointed tips. Declivous face of the propodeum with posteriorly converging sides.

Petiole with distinctly differentiate anterior and posterior faces; anterior face truncate; posterior face sloping backwards. Petiolar sides with a broad, short, pointed, lateral spine directed backwards. Postpetiole convex, bearing in the middle of the node a superficial, incomplete "U" shaped carina; postpetiolar spines short, broad, arising from the anterior border of the postpetiole and directed laterally.

Gaster weakly protruding anterolaterally and with a marginate carina not reaching the stigma backwards.

Legs. As in the soldier but with narrower femora.

Sculpture. Head, pronotum and mesonotum minutely punctate and covered by small, superficial foveae smaller than their interspaces. Ventral part of the head, propleurae and basal face of the propodeum minutely and superficially punctate and with large, deep and dense foveae. Posterior face of the petiole, of the postpetiole, lower mesopleurae, distal half of the outer face of the femora and outer face of the tibiae minutely reticulate-punctate and with dense, oval foveae; this same type of sculpture but the foveae more round on the upper mesopleurae. Lateral and posterior border of the gastral tergites and posterior border of the sternites minutely reticulate. Remaining parts of the gaster shining and with small, superficial foveae denser on the anterolateral part of the first tergite. Legs superficially reticulate.

Pilosity. Each fovea bearing an appressed hair of size proportional to the size of the fovea. Legs and posterior border of the gastral segments with erect, slightly clavate hairs.

Colour. Shining black. First gastral tergite with a pair of yellowish-white, oval spots on the middle of the sides.

Measurements (in mm) and indices: TL 11.04-12.04; HL 2.32-2.60; HW 2.60-2.92; EL 0.60-0.64; PW 2.48-2.84; PeW 1.16-1.44; PpW 1.32-1.50; HBaL 1.04-1.08; HBaW 0.35-0.40; CI 112.1-112.3; PI 102.8-104.8; PPeI 197.2-213.8; PPpI 187.9-189.3; HBal 33.6-37.0.

Type Material

de Andrade and Baroni Urbani (1999) - Worker and soldier. Type locality: Canal Zone (Panama). Type material: 8 workers and 10 soldiers labelled "Panama, Canal Zone, Bierig, 1930" in Naturhistorisches Museum Basel (examined).

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 263, queen described, page 259, combination in Cephalotes, revived from synonymy and raised to species).
  • Kempf, W. W. 1951. A taxonomic study on the ant tribe Cephalotini (Hymenoptera: Formicidae). Rev. Entomol. (Rio J.) 22: 1-244 (page 204, Junior synonym of multispinus)
  • Santschi, F. 1931d. Fourmis de Cuba et de Panama. Rev. Entomol. (Rio J.) 1: 265-282 (page 274, soldier, worker described)