Cephalotes supercilii

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

De Andrade 1999 Cephalotes OCR - Copy-643 Cephalotes-supercilii.jpg

Nothing is known about the biology of Cephalotes supercilii.

Identification

A member of the fiebrigi clade differing from its next outgroup species, Cephalotes fossithorax, in the worker by the sides of the frontal carinae with erect, long, pointed hairs, and, in the soldier and in the gyne, by the same type of hairs but extended from the sides of the frontal carinae to those of the head. The unique soldier of supercilii has the mesonotal sides with the same integumental pits as fossithorax, although much smaller. (de Andrade and Baroni Urbani 1999)

Keys including this Species

Distribution

Distribution based on Regional Taxon Lists

Neotropical Region: Argentina (type locality), Ecuador.

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.

  • supercilii. Cephalotes supercilii De Andrade, in De Andrade & Baroni Urbani, 1999: 639, fig. 299 (w.q.) ARGENTINA.

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

Description

Worker

Head broader than long. Vertexal angles round. Vertexal margin concave. Frontal carinae not upturned over the eyes. Mandibles laterally carinate.

Mesosoma gently convex in side view. Scapular angles visible in dorsal view. Pronotum with a narrow lateral lamella with three pairs of irregular teeth, the first pair more pointed and the second and third ones more angulate. Sides of mesonotum with a pair of small teeth. Promesonotal suture superficially impressed. Propodeal suture weakly impressed. Propodeum with differentiate basal and declivous faces and with the sides narrowing backwards; sides of the basal face with two pairs of teeth, the first pair simply angulate and the second one larger and pointed; sides of the declivous face unarmed or with a pair of minute denticles.

Petiole anteriorly truncate; its anterior border superficially concave medially. Petiolar spines arising from the anterior face of the petiole, pointed and curved backwards. Postpetiole as broad as the petiole; its lateral expansions broad, developed anteriorly, curved and pointed backwards.

Gaster suboval, with a pair of broad, anterolateral lobes.

Mid and hind femora not angulate; mid and hind basitarsi flat and with subparallel sides.

Sculpture. Body minutely reticulate, the reticulation less impressed on the posterior half of the first gastral sternite which is shining. Head, mesosoma, pedicel, gaster and outer face of the femora and of the tibiae foveolate, the foveae larger on the posterior third of the head dorsum and on the pronotum, sparser on the frons, shallower on the frontal carinae, irregular on the ventral part of the head, absent on the upper pleurae, more oval and superficial on the pedicel, on the gaster and on the legs. Ventral part of the head and lower propleurae with additional irregular, longitudinal, thin rugosities.

Pilosity. Body with three types of hairs: (1) appressed and generally originating from each fovea, of size proportional to the one of the respective fovea, i.e. larger on the posterior third of the head dorsum and on the pronotum, shorter and thinner on the body parts without foveae; (2) pointed, long on the border of the frontal carinae, sparse on the gastral sternites, rare on the coxae and on the ventral face of the femora; similar but slightly longer and rare hairs on the posterior borders of the second and third gastral sternites; (3) short, truncate and rare on the posterior border of the remaining gastral tergites and on the legs.

Colour. Black, gaster and legs lighter. Frontal carinae, mesosomal and peduncular spines and outer face of the tibiae yellowish to light brown.

Measurements (in mm) and indices: TL 4.48-4.52; HL 1.04-1.06; HW 1.12; EL 0.29-0.30; PW 1.00; PeW 0.56-0.58; PpW 0.54-0.59; HBaL 0.39; HBaW 0.10; CI 105.7-107.7; PI 112.0; PPeI 172.4-178.6; PPpI 169.5-185.2; HBaI 25.6.

Queen

Differing from the soldier, besides than in the usual caste-dependent traits, in the following details:

Head almost as broad as long. Floor of the disc more convex posteriorly and flat anteriorly. Vertexal angles simply angulate medially. Humeral angles simply angulate. Pronotal sides straight. Mesonotum and scutellum flat. Sides of the basal face with a small pair of short, round denticles and with a pair of large, stout teeth, slightly diverging and directed backwards. Petiolar sides with a pair of very small denticles. Postpetiolar spines less developed and smaller. Gaster longer and with more protruding lobes.

Sculpture. Foveae denser on the ventral part of the head, less regular and sparser on the mesosoma Propleurae with denser rugosities.

Pilosity. Head dorsum with hair types (1) and (2) almost in the same proportions. Mesosoma, pedicel, first gastral tergite and legs with rare, subtruncate hairs of type (2). Posterior border of the gastral tergites with denser hairs of type (4).

Colour. As in the soldier except for the presence of a pair of yellow spots close to the posterior border of the first gastral tergite.

Measurements (in mm) and indices: TL 9.06; HL 1.70; HW 1.72; EL 0.38; PW 1.72; PeW 0.69; PpW 0.85; HBaL 0.50; HBaW 0.16; CI 101.2; PI 100.0; PPeI 249.3; PPpI 202.3; HBaI 32.0.

Type Material

Holotype: worker, Argentina, Rosario, W. M. Davis Museum of Comparative Zoology. Paratype: 1 gyne, same data as the holotype MCZ.

Etymology

This species is named from the Latin supercilium (= eyebrow), referred to the long hairs on the border of the frontal carinae.

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