Cephalotes basalis

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Cephalotes basalis
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Cephalotes
Species: C. basalis
Binomial name
Cephalotes basalis
(Smith, F., 1876)

Cephalotes basalis P casent0900246.jpg

Cephalotes basalis D casent0900246.jpg

Specimen Label

Synonyms

This ant has been collected in a variety of moist forest habitats as well as at the edge of pastures, in canopy fogging samples and from a beach (presumably the beach vegetation). Little else is known about its biology.

Identification

A member of the basalis clade characterised, in the worker, by the pronotal lamellae anteriorly and posteriorly obtuse and by the petiolar spines shorter than the basal face of the propodeum, and, in the soldier and gyne, by the vertex with a pair of developed spines. (de Andrade and Baroni Urbani 1999)

Keys including this Species

Distribution

Distribution based on Regional Taxon Lists

Neotropical Region: Brazil (type locality), Colombia, Costa Rica, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama.

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.

  • basalis. Cryptocerus basalis Smith, F. 1876d: 608 (q.) BRAZIL. De Andrade & Baroni Urbani, 1999: 273 (m.). Combination in Paracryptocerus: Kempf, 1951: 232; in Zacryptocerus: Hespenheide, 1986: 395; in Cephalotes: De Andrade & Baroni Urbani, 1999: 269. Senior synonym of multispinus: De Andrade & Baroni Urbani, 1999: 269.
  • multispinus. Cryptocerus cordatus r. multispinus Emery, 1890b: 75, pl. 9, fig. 5 (w.) COSTA RICA. [Also described as new by Emery, 1894k: 59.] Emery, 1894c: 202 (s.); Forel, 1899c: 49 (q.); Wheeler, G.C. & Wheeler, J. 1954b: 155 (l.). Combination in Cryptocerus (Paracryptocerus): Emery, 1915i: 192; in Paracryptocerus: Kempf, 1951: 204; in Zacryptocerus: Brandão, 1991: 387. Raised to species: Dalla Torre, 1893: 143; Emery, 1894c: 201. Junior synonym of basalis: De Andrade & Baroni Urbani, 1999: 269.

Description

Worker

Kempf (1951) of synonymized multispinus - Length 7.1 mm. Median head length 1.75 mm; Weber's length of thorax 2.34 mm. Black.

Head subopaque, subquadrate. Mandibles finely reticulate-punctate, finely reticulate-rugose. Sides of head sinuate, conspicuously converging in front, concave in front of, convex and visibly upturned above, the eyes. Frontal carinae prolonged behind the scrobe, as a visible carina, which reaches the sharply angulate, subspinose occipital corner. Occipital border concave, sharply crested laterad, the middle piece slightly convex. Upper surface of head little convex, finely reticulate-punctate, densely foveolate, each foveola containing a broad, appressed, short, canaliculate, silvery scale. Checks strongly marginate beneath, densely covered with large silvery scales. Lower surface of head more fulgid, sparsely scaled.

Thorax subopaque. Sides of lateral pronotal plates converging behind, the anterior angle acute, subspinose, the posterior angle subrectangular. Promesonotal suture obsolete. Mesonotum with a strong, lateral spine. Mesoepinotal suture vestigial. Basal face of epinotum with a broad, plate-like, triangular, lateral tooth, with an accessory smaller tooth arising from its anterior border, and a longer, subacuminate, posterior spine, projecting obliquely backward and slightly upward, subequal to the length of the basal face. Promesonotum somewhat convex in profile. Dorsum of thorax finely reticulate-punctate and foveolate, each foveola containing an appressed canaliculate scale, as on head. Laterotergite of pronotum longitudinally striated. Sides of thorax densely scaled below, smooth above. Declivous face of epinotum finely reticulate, very finely and distantly longitudinally rugulose, its sides marginate. Femora slightly less inflated than in femoralis, the posterior side only finely reticulate, and subfulgid. Hind basitarsus elongate, broadened and flattened proximad.

Petiole and postpetiole subopaque, sculptured as upper surface of thorax, with a median longitudinal carinule above, arising on the postpetiole distinctly behind the anterior border which is slightly impressed mesad. Petiole with very long, slightly raised, lateral spines.

Gaster subopaque, broadly cordiform, very convex above. First gastral tergite slightly emarginate in front mesad, crested antero-Iaterad, sculptured as dorsal surface of thorax, foveolae more or less obsolete, but similarly scaled; scales large, canaliculate. First sternites with a few longitudinal rugosities on the sides. Erect hair confined to the terminal tergites and the sternites of the gaster, and few erect setulae on the internal curvature of the frontal carinae.

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL 5.96-7.20; HL 1.42-1.72; HW 1.72-2.20; EL 0.48-0.56; PW 1.68-2.12; PeW 1.28-1.68; PpW 1.08-1.40; HBaL 0.63-0.85; HBaW 0.22-0.29; CI 121.1-130.6; PI 101.9-108.5; PPeI 126.2-139.4; PPpI 150.0-170.4; HBaI 31.8-42.0

Soldier

Kempf (1951) of synonymized multispinus - Length 10 mm. Median head length 2 .73 mm; Weber's length of thorax 2.93 mm. Black.

Head subfulgid, subquadrate. Mandibles finely reticulate, almost smooth, sparsely foveolate. Frontal carinae rounded anteriorly, slightly raised laterally, continued behind the scrobe as a distinct carina, reaching the occipital corner. Upper surface of head little convex, vertex with two short teeth above the truncate occiput, which is submarginate above mesad and laterad. Cheeks marginate beneath, with a strong carina extending back to the occipital corner, densely foveolate and scaled. Upper and lower surface of head smooth, covered with small foveolae. Lower surface of head superficially reticulate, the foveolae sparser containing a distinctly visible hair.

Thorax fulgid. Pronotum greatly expanded laterad, the anterior border scarcely arcuate, the lateral borders subparallel, sharply crested, converging mesad, behind the conspicuous, medially interrupted, transverse pronotal crest. Promesonotal suture distinct. Mesonotum with a strong lateral apically rounded tooth. Mesoepinotal suture impressed, greatly arcuate caudad. Basal face of epinotum with a strong, broad triangular tooth on each side, and a posterior strongly divergent, somewhat upturned apically, stout spine the posterior border of which is continuous with the marginate posterior border of the basal face. Dorsum of thorax and laterotergite of pronotum mostly smooth, vestigially and very finely reticulate, sparsely foveolate, the foveolae larger, rather dense, containing visible scales on epinotum. Sides of thorax mostly smooth, with a patch of very dense silvery scales on mesopleura and metapleura. Declivous face perpendicular to basal face, smooth and fulgid.

Petiole with smooth anterior truncate face, which is marginate above. Lateral spines greatly upturned, upper face densely scaled and foveolate. Postpetiole narrower than petiole, lateral spines not upturned. Sculpture as on petiole.

Gaster fulgid above, subfulgid below. Broadly cordiform, slightly emarginate in front mesad, narrowly crested antero-laterad. First gastral tergite with dense large canaliculate scales on the anterior corners and on the apical third, scales and foveolae more or less obsolete discad. Sternites finely reticulate, more sparsely scaled. Erect hair confined to apical third of gaster.

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL 8.48-9.52; HL 2.12-2.642; HW 2.76-3.16; EL 0.60-0.65; PW 2.60-3.00; PeW 1.68-2.00; PpW 1.46-1.60; HBaL 0.79-0.84; HBaW 0.32-0.35; CI 119.7-130.2; PI 104.0-108.8; PPeI 142.8-164.4; PPpI 178.1-189.7; HBal 40.0-43.7.

Queen

de Andrade and Baroni Urbani (1999) - Head convex. Frontal carinae broadly expanded anteriorly, slightly converging before the eyes, slightly upturned over them, and ending in an obtuse tooth on the vertexal angles. Vertex with a pair of thick teeth connected by a faint carina. Mandibles laterally carinate.

Mesosoma almost flat in profile. Humeral angles with a short, obtuse tooth. Pronotal carina concave and marked on the sides, convex and faint in the middle. Mesonotum and scutellum 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 concavity, the first pair short, triangular, the second one long and pointed. Declivous face of the propodeum with converging sides posteriorly.

Petiole with distinctly differentiated anterior and posterior faces; anterior face oblique with gently convex anterior border; posterior face sloping backwards, with a pair of pointed lateral spines, half of the petiolar length and directed backwards. Postpetiole broadly convex in the middle, and bearing a faint, incomplete "V" shaped carina; postpetiolar spines arising from the anterior border of the postpetiole and directed laterally.

Gaster marginate anteriorly by a strong carina not surpassing the stigma backwards.

Legs. Mid and hind femora angulate. Mid and hind basitarsi flat and broad at the base.

Sculpture. Head dorsum minutely punctate and covered with small, superficial foveae smaller than their interspaces. Mesosoma and pedicel superficially punctate, superficially shining, with foveae larger than those on the head dorsum, sparser on the anterior half of the pronotum and mesonotum, denser on the posterior half of the pronotum, on the scutellum, on the propodeum, on the pedicel and on the mesopleurae. Ventral face of the head and proplcurae with large foveae and almost shining. Metapleurae, declivous face of the propodeum, anterior face of the petiole, gaster and legs superficially reticulate-punctate and slightly shining. Small, sparse, superficial foveae on the centre of the anterior fourth of the first gastral tergite, on the first gastral sternite and on the legs, denser on the sides of the anterior fourth of the first gastral tergite and on the remaining gastral segments.

Pilosity. Each fovea bearing an appressed, canaliculate hair, of thickness proportional to the size of the foveae. Gaster, except the centre of the first tergite, distal part of femora, outer face of the tibiae with dense, appressed, thick canaliculate h ai rs. Apex of the gaster with long, erect, truncate hairs, rare on the legs.

Colour. Black. Anterior third of the first gastral tergite with an orange spot on each side.

Measurements (in mm) and indices: TL 11.72-13.07; HL 2.64-2.72; HW 2.72-2.96; EL 0.60-0.65; PW 2.76-3.00; PeW 1.64-1.76; PpW 1.56-1.80; HBaL 0.90-1.08; HBaW 0.35-0.38; CI 107.8-108.8; PI 95.9-104.2; PPeI 165.9-186.5; PPpI 162.2-182.9; HBaI 35.2-38.9.

Male

de Andrade and Baroni Urbani (1999) - Head (eyes included) about 1/3 broader than long; vertexal margin superficially carinate, straight in the middle and curved laterally, diverging into two obtuse angles. Vertex and ocelli protuberant. Eyes broadly convex, in the middle of the sides of the head. Frontal carinae not raised and shortly diverging backwards. Frons gently convex and separate from the clypeus by a superficial furrow. Clypeus convex, its anterior face almost truncate. Mandibles with a superficial lateral carina. Scapes thick, twice as long as the first funicular joint; remaining funicular joints thickening from the base to the apex.

Mesosoma. Pronotum in dorsal view with a slightly marked scapular angle and broadening backwards. Mesonotum convex; median Mayrian carina and parapsidal furrows weakly impressed.

Scutellum convex, its sides converging posteriorly. Propodeum with differentiate basal and declivous faces; basal face with the sides gently convex and converging posteriorly towards the declivous face, the latter converging posteriorly with the lateral carinae.

Petiole slightly narrower than the postpetiole, with truncate and medially concave anterior face and with the posterior face sloping backwards; petiolar sides with a small, obtuse denticle medially. Postpetiole convex dorsally; postpetiolar sides with a small, pointed denticle anteriorly and converging posteriorly.

Gaster narrower than the mesosoma.

Wings as in the gyne.

Sculpture. Head, propleurae and pedicel reticulate and with small, superficial foveae dense on the vertexal angles, on the frons and on the sides of the pedicel, rare close to the eyes, on the propleurae and on the dorsum of the pedicel. Mesosoma reticulate and with deeper and larger foveae than on the frons. Propodeum with irregularly longitudinal rugosities. Mesopleurae anteriorly superficially reticulate and with dense, superficial, small foveae, this sculpture less impressed posteriorly. Metapleurae feebly shining, with longitudinal rugosities on the lower part. Gaster and legs reticulate, the reticulation less impressed on the legs and on the first gastral sternite.

Pilosity. Head, mesosoma and pedicel covered by dense, long, suberect hairs; similar hairs but sparse on the posterior border of the tergites, of the sternites and on the legs. Gaster and legs with appressed, thin, short hairs.

Colour. Head and mesosoma black, pedicel lighter. Gaster and femora ferrugineous. Remaining parts of the legs yellowish.

Measurements (in mm) and indices: TL 6.36-7.10; HL 0.96-1.04; HW 1.24-1.36; EL 0.56-0.57; PW 1.48-1.64; PeW 0.56-0.60; PpW 0.64-0.68; HBaL 0.72; HBaW 0.12; CI 130.8-135.5; PI 82.9-83.8; PPeI 264.3-273.3; PPpI 231.2-241.2; HBaI 16.7.

Type Material

de Andrade and Baroni Urbani (1999):

Gyne. Type locality: Chontales (Nicaragua), erroneously given as Brazil. Type material: holotype gyne in The Natural History Museum, labelled as type, "Braz.", with the reference number 70 59, examined.

Cryptocerus cordatus multispinus. Worker. Type material: one syntype worker in the Museo Regionale di Scienze Naturali, Torino (Casolari & Casolari Moreno, 1980: 84), not available for the present study; 5 workers from Jimenez, Alajuela and S. Jose (Costa Rica) in Museo Civico di Storia Naturale, Genoa, examined. 6 syntype workers and one syntype soldier (Costa Rica) in Museo Civico di Storia Naturale, Genoa and Musee d'Histoire Naturelle Genève, examined. Synonymy suggested by R. R. Snelling, personal communication, confirmed by our examination of the type material.

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 273, male described, page 269, Combination in Cephalotes and senior synonym of multispinus)
  • Hespenheide, H.A. 1986. Mimicry of ants of the genus Zacryptocerus. J. N. Y. Entomol. Soc. 94: 394-408 (page 395, Combination in Zacryptocerus)
  • Kempf, W. W. 1951. A taxonomic study on the ant tribe Cephalotini (Hymenoptera: Formicidae). Rev. Entomol. (Rio J.) 22: 1-244 (page 232, Combination in Paracryptocerus)
  • Smith, F. 1876d. Descriptions of new species of Cryptoceridae, belonging to the genera Cryptocerus, Meranoplus, and Cataulacus. Trans. Entomol. Soc. Lond. 1876: 603-612 (page 608, queen described)