Cephalotes adolphi

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Cephalotes adolphi
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Cephalotes
Species: C. adolphi
Binomial name
Cephalotes adolphi
(Emery, 1906)

Cephalotes adolphi P casent0904906.jpg Cephalotes adolphi D casent0904906.jpg Specimen Label

This rare species is known on two workers only: the holotype from Coxipo and a second one collected recently not very far from the type locality. (de Andrade and Baroni Urbani 1999)

Identification

A member of the angustus clade differing from its sister species, Cephalotes dentidorsum, in the worker by the less shining body, opaque and with more impressed sculpture; the difference between the two micro sculptures is particularly impressive on the gaster. (de Andrade and Baroni Urbani 1999)

Keys including this Species

Distribution

Distribution based on Regional Taxon Lists

Neotropical Region: Brazil (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

Known only from the worker caste.

Nomenclature

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

  • adolphi. Cryptocerus adolphi Emery, 1906c: 172, fig. 33 (w.) BRAZIL. Combination in Paracryptocerus (Harnedia): Kempf, 1958a: 86; in Zacryptocerus: Brandão, 1991: 384; in Cephalotes: De Andrade & Baroni Urbani, 1999: 733. See also: Kempf, 1960f: 439.

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 gently convex above, broader than long. Frontal carinae diverging backwards, incised in front and upturned above eyes. Vertexal angles bearing a subtruncate, broad, superficially crenulate lamella. Vertexal margin concave and marginate. Clypeal suture superficially impressed. Mandibles with a thin, short lateral carina.

Mesosoma declivous posteriorly. Scapular angles visible in dorsal view. Pronotal sides with a pair of pointed, triangular teeth followed by a pair of broad, stout, triangular lobes pointed upwards; apex of the pronotal lobes pointed and with a third minute denticle posteriorly. Promesonotal suture superficially impressed on the sides. Propodeum sloping backwards, with weakly differentiate basal and declivous faces; declivous face superficially concave in the middle and as long as the basal one. Propodeal sides with 4 pairs of pointed denticles, the first and the third pairs subequal and shorter, the second pair much longer, the fourth pair minute.

Petiole with oblique anterior face, with a pair of denticles dorsally and a pair of long, pointed, spines laterally. Postpetiole slightly broader than petiole; its node gently convex; postpetiolar spines long, thin, directed forwards at the base and curved at the apex.

Gaster oval. Anterolateral gastral border with a semitransparent lamella not surpassing the stigma posteriorly.

Hind femora without angles or denticles. Mid and hind basitarsi with subparallel sides.

Sculpture. Head dorsum minutely punctate and covered by small, round, superficial, variably clumped foveae, absent on the frontal carinae. Ventral part of the head superficially and minutely reticulate and with shallower, oval foveae on the anterolateral parts. Mesosoma, pleurae, pedicel, outer face of the femora and of the tibiae minutely and superficially punctate and with dense, oval foveae, sparser on the pleurae, shallower on the pedicel, on the outer face of the femora and of the tibiae. First gastral tergite with deep reticulation and covered by dense, superficial, oval foveae similar to those of the mesosoma but smaller. Remaining gastral segments and parts of the legs reticulate, the reticulation absent on the posterior half of the first gastral sternite.

Pilosity. Each fovea with an appressed canaliculate hair. Mandibles, border of the frontal carinae, sides of the postpetiole, posterior half of the first gastral tergite, and legs with rare, suberect, subclavate hairs. Posterior border of the gastral tergites and sternites with truncate hairs, rare on the sternites. Sternites with long, sparse, pointed hairs.

Colour. Light brown lighter on the frontal carinae, on the anterior third of the first gastral tergite, on the femora and on the tibiae.

Measurements (in mm) and indices: TL 4.00; HL 1.04; HW 1.26; EL 0.32; PW 0.95; PeW 0.64; PpW 0.68; HBaL 0.40; HBaW 0.08; CI 121.1; PI 132.6; PPeI 148.4; PPpI 139.7; HBaI 20.0.

Type Material

de Andrade and Baroni Urbani (1999) - Worker. Type locality: Coxipo (Mato Grosso). Type material a worker (holotype) labelled “Coxipu, IX.900, typus”, in Museo Civico di Storia Naturale, Genoa, examined.

References

  • Brandão, C. R. F. 1991. Adendos ao catálogo abreviado das formigas da região Neotropical (Hymenoptera: Formicidae). Rev. Bras. Entomol. 35: 319-412 (page 384, Combination in Zacryptocerus)
  • De Andrade, M. L.; Baroni Urbani, C. 1999. Diversity and adaptation in the ant genus Cephalotes, past and present. Stuttg. Beitr. Naturk. Ser. B (Geol. Paläontol.) 271: 1-889 (page 733, Combination in Cephalotes)
  • Emery, C. 1906c [1905]. Studi sulle formiche della fauna neotropica. XXVI. Bull. Soc. Entomol. Ital. 37: 107-194 (page 172, fig. 33 worker described)
  • Kempf, W. W. 1958a. New studies of the ant tribe Cephalotini (Hym. Formicidae). Stud. Entomol. (n.s.) 1: 1-168 (page 86, Combination in Paracryptocerus (Harnedia))
  • Kempf, W. W. 1960f. Miscellaneous studies on Neotropical ants (Hymenoptera, Formicidae). Stud. Entomol. (n.s.) 3: 417-466 (page 439, see also)