Cephalotes goniodontus

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

De Andrade 1999 Cephalotes OCR - Copy-312 Cephalotes-goniodontus.jpg

Nothing is known about the biology of Cephalotes goniodontus.

Identification

A member of the multispinosus clade characterised, in the worker, by the sides of the propodeum armed with a broad, triangular tooth. Easily distinguishable from Cephalotes multispinosus by its sculpturation and by the absence of lamellae behind the propodeal teeth. (de Andrade and Baroni Urbani 1999)

Keys including this Species

Distribution

Distribution based on Regional Taxon Lists

Neotropical Region: Mexico (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.

  • goniodontus. Cephalotes goniodontus De Andrade, in De Andrade & Baroni Urbani, 1999: 307, figs. 132, 133 (s.w.) MEXICO. [Cephalotes goniodontus Baroni Urbani, 1998: 326. Nomen nudum.]

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

Description

Worker

Kempf (1951), of the synonymized multispinosus - Length 6 mm. Median head length 1.41 mm; Weber's length of thorax 1.63. Black; the following ferruginous: Frontal carinae, tip of last funicular segment, tips of femora and tibiae. Pale yellowish: crests of thorax and peduncular spine. Yellow: a single spot on each anterior corner of the gaster.

Head subquadrate, subopaque. The anterior corners greatly rounded, the posterior corners subangulate, the sides parallel. Occipital border shallowly emarginate mesad, almost straight, with a very narrow light crest on each side. Frontal carinae not crenulate, without projecting setae from the border. Eyes very small, the maximum diameter less than 1/4 of the median head length. Vertex with a pair of small denticules. Upper surface of head densely foveolate, each foveola containing a short, broad, appressed, silvery, flat hair.

Thorax subopaque. Anterior border rounded, shoulders not separate from the lateral projections of pronotum. Sides of pronotum crested; the anterior half of the crest greatly projecting and bidenticulate, the posterior half constricted and narrow. Promesonotal suture vestigial. Mesonotum with a small lateral denticule. Mesoepinotal suture more or less distinct. Epinotum not differentiated into distinct basal and declivous faces, with a broad, large, flattened triangular tooth projecting from the anterior half of the lateral border, the posterior half carinate. Upper surface of thorax, except a small area mesially in front of the petiolar insertion, very finely shagreened, densely and coarsely foveolate, as the upper surface of head. Laterotergite of pronotum and sides of thorax finely reticulate-punctate, the laterotergite longitudinally striated, the remaining parts rugulose. Outer face of fore coxae finely longitudinally striated. Hind femora sharply angulate and denticulate above the half.

Petiole and postpetiole flattened above, the sides with a distinctly set off spine, the petiolar spine recurved, the postpetiolar spine pointing forward at base, recurved backward at apex.

Gaster subopaque, emarginate in front mesally, narrowly crested antero-laterad. All scales golden.

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL 5.40-5.92; HL 1.24-1.36; HW 1.64-1.70; EL 0.32-0.33; PW 1.42-1.52; PeW 0.69-0.76; PpW 0.77-0.82; HBaL 0.61-0.62; HBaW 0.15-0.16; CI 125.0-132.2; PI 111.8-115.5; PPeI 205.8-211.1; PPpI 184.4-185.4; HBaI 24.6-25.8.

Soldier

Kempf (1951), of the synonymized multispinosus - Length 7.7 mm. Median head length 1.78 mm. Weber's length of thorax 2.07 mm. Color as in worker. Quite similar to the worker, with the following differences: Upper surface of head subfulgid, not as shiny as in the race biguttatus, rather coarsely and densely foveolate. Each of the teeth on vertex sends out an oblique carina towards the sides, fading out shortly before reaching the lateral border of the head. Occipital angle rounded and crested. Pronotum with a bidenticulate lateral expansion, the sides converging obliquely towards the mesonotum behind the second denticule. Mesonotum with a blunt lateral lobe. Sculpture of thorax as coarse as on upper surface of head. Epinotum with a flat, triangular, large tooth, without a transparent crest behind. The basal and declivous faces slightly differentiated. Declivous face not excavated below. Spines of the peduncular segments shorter, less acute than in worker.

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL (approximate from two different specimens, one without gaster and one without head) 7.10-7.28; HL 1.60; HW 2.12; EL 0.40; PW 1.88-1.96; PeW 0.85-0.89; PpW 0.90-0.98; HBaL 0.70-0.72; HBaW 0.18; CI 132.5; PI 112.8; PPeI 220.2-221.2; PPpI 200.0-208.9; HBaI 25.0-25.7.

Type Material

Holotype worker from Compostela (Mexico), 22.IV.1933, W. M. Wheeler (Museum of Comparative Zoology); paratypes: 1 worker (same data as the holotype), 1 worker and 2 soldiers from vic. Compostela (Mexico), 28,V, 1 933, W. M. Wheeler, in MCZ.

Etymology

From the Greek term for angle and tooth, referred to the shape of the propodeal angles.

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 307, figs. 132, 133 soldier, worker described)
  • Kempf, W. W. 1951. A taxonomic study on the ant tribe Cephalotini (Hymenoptera: Formicidae). Rev. Entomol. (Rio J.) 22: 1-244.