Cephalotes conspersus

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Cephalotes conspersus
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Cephalotes
Species: C. conspersus
Binomial name
Cephalotes conspersus
(Smith, F., 1867)

Cephalotes conspersus P casent0901462.jpg

Cephalotes conspersus D casent0901462.jpg

Specimen Label

Synonyms

Nothing is known about the biology of Cephalotes conspersus.

Identification

A member of the angustus clade differing from its sister species, Cephalotes palta, in the worker by the first gastral tergite bicoloured and, in the soldier, by the foveae on the disc sparser and larger (de Andrade and Baroni Urbani 1999).

Keys including this Species

Distribution

Fernandez et a1. (1996) report this species from the Colombian state of Meta. We saw no Colombian specimens referable to this species. Although the record from Colombia is plausible, there is a chance that the specimens in question may refer to the closely related palta described from Colombia. (de Andrade and Baroni Urbani 1999)

Distribution based on Regional Taxon Lists

Neotropical Region: Brazil (type locality), Ecuador, Trinidad and Tobago.

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.

  • conspersus. Cryptocerus conspersus Smith, F. 1867: 523, pl. 26, fig. 1 (w.) BRAZIL. Combination in Paracryptocerus: Kempf, 1951: 232; in Zacryptocerus: Brandão, 1991: 385; in Cephalotes: De Andrade & Baroni Urbani, 1999: 697. Senior synonym of variegata: Kempf, 1958d: 108.
  • variegata. Cryptocerus denticulatus var. variegata Forel, 1911e: 262 (w.) BRAZIL. Junior synonym of targionii: Kempf, 1958a: 94; of conspersus: De Andrade & Baroni Urbani, 1999: 697.

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) - Head convex above, subquadrate. Frontal carinae superficially crenulate, diverging backwards, slightly converging in front, little upturned above the eyes. Vertexal angles truncate, bearing a pair of small, obtuse, membranaceous denticles, often with a minute notch in the middle. Vertexal margin concave and laterally connected to the denticles by means of a thin carina. Clypeal suture superficially impressed. Mandibles with a faint, thin, short, lateral carina.

Mesosoma gently convex. Scapular angles free. Pronotal sides with three pairs of short, membranaceous teeth, the first and the second pair triangular, the third pair, broader than the others, obtuse. Promesonotal suture poorly impressed. Mesonotum with a pair of triangular denticles with truncate tip. Propodeal suture more impressed on the sides. Propodeum with poorly differentiate basal and declivous faces; declivous face concave in the middle and shorter than the basal one. Propodeal sides with five, rarely six pairs of pointed denticles, sometimes the first, third, fifth and sixth pairs thinner and much smaller than the second and fourth pairs.

Petiole with truncate anterior face; its posterior face sloping and separate from the anterior one by a pair of minute denticles. Sides of the petiole with a pair of pointed, thin spines directed slightly backwards. Postpetiole convex and as broad as the petiole; postpetiolar spines directed slightly forwards at the base and curved at the apex.

Gaster oval. Anterolateral gastral border with semitransparent lamella reaching the stigma.

Hind femora subangulate to angulate.

Sculpture. Head dorsum reticulate and covered by superficial foveae as broad as their interspaces and slightly denser on the vertexal angles. Frontal carinae reticulate only. Ventral face of the head reticulate and with few, faint, longitudinal rugulae close to the hypostoma. Mesosoma, posterior face of the petiole, and postpetiole with the same sculpture as on the vertexal angles, the foveae more oval on the propodeum and less impressed on the pedicel. Middle of the declivous face of the propodeum, anterior face of the petiole, gaster and legs simply reticulate. Pleurae reticulate and with superficial, longitudinal striae. First gastral sternite with superficial, oval piligerous punctures. Middle of the posterior half of the first gastral sternite shining.

Pilosity. Each fovea with an appressed canaliculate hair, both slightly longer on the propodeum and on the pedicel. Mandibles, border of the frontal carinae and legs with sparse, suberect hairs. Extensor face of the legs and gaster with dense, appressed hairs as those on the propodeum, thinner on the gaster. Posterior borders of the gastral tergites with clavate hairs; gastral sternites with the same clavate hairs as the tergites and rare, long and pointed hairs.

Colour. Black. Frontal carinae, distal part of the scapes, three first funicular joints, thoracic and peduncular spines, distal half of the femora, tibiae and tarsomeres yellowish to ferruginous. First gastral tergite with the following black parts: a pair of oval anterolateral spots and a lozenge in the middle, the rest ferruginous.

Measurements (in mm) and indices: TL 3.46-3.92; HL 0.88-0.94; HW 0.96-1.08; EL 0.28-0.30; PW 0.76-0.88; PeW 0.50-0.54; PpW 0.50-0.54; HBaL 0.35-0.37; HBaW 0.07; CI 109.1-114.9; PI 122.7-126.3; PPeI 152.0-162.9; PPpI 152.0-162.9; HBaI 18.9-20.0.

Soldier

de Andrade and Baroni Urbani (1999) - (tentative attribution). - Very similar to that of palta from which it differs in the following details: Floor of the disc less concave anteriorly. Humeral angles pointed. Pronotal sides subparallel. Pronotal carina superficially marked. Promesonotal suture impressed. Propodeum with well differentiate basal and declivous faces. Sides of the basal face anteriorly with three denticles, the first denticle smaller the others and the third one curved upwards. Declivous face concave in the middle; its sides converging posteriorly and bearing a minute denticle. Postpetiole more convex and with the "U" shaped carina less marked. Gastral lobes more oval. Anterolateral border of the first gastral sternites with a very thin margin not reaching the stigma posteriorly. Fore femora slightly incrassate. Hind femora without angles or denticles. Hind basitarsi slightly more compressed apically than distally and without broad base. Hind femora subangulate.

Sculpture. Foveae on the head larger and sparser on the dorsum, shallower on the ventral part. Propleurae with longitudinal striae on the lower part. Anterior fourth of the first gastral tergite with sparser foveae.

Pilosity. Mesosoma and pedicel without subclavate hairs.

Colour. Ventral part of the head including half of its sides, mesosoma, pedicel, coxae, femora, mid and hind tarsi and gaster black. Head dorsum, including the dorsal half of the sides, apex of femora, fore tibiae and fore tarsi, outer face of mid and hind tibiae, and tarsomeres yellowish-orange. Gaster with two pairs of yellow spots on the first tergite, the first pair anterolaterally, the second one placed on the postero-lateral half of the gaster.

Measurements (in mm) and indices: TL 4.92; HL 1.40; HW 1.32; EL 0.32; PW 1.16 PeW 0.56; PpW 0.59; HBaL 0.36; HBaW 0.10; CI 94.3; PI 113.8; PPeI 207.1; PPpI 196.6; HBaI 27.8.

Type Material

Holotype Specimen Labels

The following notes on F. Smith type specimens have been provided by Barry Bolton (details):

Cryptocerus conspersus

Presence of the holotype in Oxford University Museum of Natural History has been confirmed by W.W. Kempf.

de Andrade and Baroni Urbani (1999) - Worker. Type locality: Rio Amazonas, Brazil. Type material: holotype, unique, worker labelled “121, Type, Amaz, Cryptocerus conspersus. Sm. Trans Ent. Soc., Cryptocerus conspersus Sm. 1867 Holotypus, Paracryptocerus conspersus (F. Sm.) 1867 det. Kempf 1957, Type Hym. 1045”, in Oxford University Museum of Natural History, examined. Kempf, 1958 b.

Cryptocerus denticulatus var. variegata. Worker. Type locality: Amazonas. Type material: 3 syntype workers labelled “Amazonas, H. W. Bates S.”, 1 in Musee d'Histoire Naturelle Genève, 2 in Zoologische Staatssammlung, Munich, examined.

References