Cephalotes cordiae

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Cephalotes cordiae
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Cephalotes
Species: C. cordiae
Binomial name
Cephalotes cordiae
(Stitz, 1913)

De Andrade 1999 Cephalotes OCR - Copy-247 Cephalotes-cordiae.jpg

The type series was collected from Cordia.

Identification

A member of the basalis clade characterised in the worker and soldier by the propodeum with only a pair of spines, and, in all castes, by the HBaI ≥ 53 (the sole known gyne has HBaI = 57.5, the highest of the clade). The workers of C. cordiae share with Cephalotes ramiphilus, its closest relative, the high HBaI (≥ 47 in both species as compared with < 43 in the other species of the clade except femoralis). The worker and the soldier of cardiae can be easily distinguished from those of ramiphilus by the presence of only one pair of spines between the basal and declivous face of the propodeum and by the obtuse anterior border of the pronotal lamellae. The gyne of cordiae differs from that of ramiphilus by the sculpture, more superficial. (de Andrade and Baroni Urbani 1999)

Keys including this Species

Distribution

Peru, Bolivia and Brazil

Distribution based on Regional Taxon Lists

Neotropical Region: Bolivia, Brazil (type locality), Peru.

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.

  • cordiae. Cryptocerus cordiae Stitz, 1913: 207, fig. 1 (s.w.) BRAZIL. Kempf, 1951: 201 (q.); De Andrade & Baroni Urbani, 1999: 245 (m.). Combination in Cryptocerus (Paracryptocerus): Emery, 1924d: 307; in Paracryptocerus: Kempf, 1951: 199; in Zacryptocerus: Brandão, 1991: 385; in Cephalotes: De Andrade & Baroni Urbani, 1999: 242.

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) - Length 6.4 mm. Median head length 1.45 mm; Weber's length of thorax 2.07 mm. Black; the following fuscous ferruginous; apex of mandibles, anterior corner of frontal carinae, three apical tarsal segments. Tip of last funicular segment orange-brown.

Head subopaque, subquadrate. Mandibles very finely reticulate-punctate, not rugulose. Sides of head not sinuate, not upturned above the eyes. Forontal carinae greatly curved mesad in front, prolonged behind the scrobe, fading out above the eyes. Occipital corner obtusely angulate, more or less rounded. Occipital border almost straight, scarcely emarginate mesad, not crested nor marginate laterad. Upper surface conspicuously convex, finely reticulate-punctate, more sparsely and somewhat vestigially foveolate, each foveola containing a small, usually simple, bright, shiny and appressed scale. Cheeks weakly to indistinctly carinate below, rather densely covered with large, silvery, appressed, canaliculate scales. Lower surface of head more fulgid, with sparser scales.

Thorax subopaque. Sides of lateral pronotal plates strongly converging caudad, their lateral border crested, the anterior corner subspinose, the posterior corner rounded. Promesonotal suture obsolete mesad. Mesonotum with a lateral, apically rounded, lobe-like tooth. Mesoepinotal suture impressed. Basal face of epinotum without a lateral tooth, sides moderately arcuate, immarginate, the posterior corner with a longer, somewhat divergent and upturned spine, shorter than the length of the basal face. Promesonotum in profile, conspicuously convex. Posterior border of basal face submarginate. Declivous face longer than basal face, the sides marginate. Dorsum of thorax finely reticulate-punctate, without distinctly impressed foveolae, scales sparse, short and simple. Sides of thorax and declivous face finely reticulate. Tibiae prismatic.

Petiole and postpetiole subequal in width, subopaque, without a median longitudinal carinule above. Spines of petiole upturned and slightly recurved.

Gaster subopaque, elongate, finely reticulate-punctate. First gastral tergite scarcely emarginate mesad, narrowly crested antero-Iaterad, with simple, minute scattered, appressed scales. Erect hairs confined to the following tergites and sternites.

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL 5.32-5.86; HL 1.36-1.48; HW 1.64-1.76; EL 0.37-0.44; PW 1.52-1.68; PeW 1.16; PpW 1.04-1.08; HBaL 0.56-0.60; HBaW 0.31-0.32; CI 118.9-120.6; PI 104.8-107.9; PPeI 131.0-144.8; PPpI 140.7-161.5; HBaI 53.3-55.3.

Soldier

Kempf (1951) - Length 7.3 mm. Median head length 1.78 mm; Weber's length of thorax 2.19 mm. Black.

Head subfulgid; subquadrate. Mandibles smooth, subfulgid, sparsely punctate. Frontal carinae greatly curved mesad in front, scarcely raised, continued behind the scrobe as a faint carina, fading out above the eyes, not reaching the rounded occipital corner. Clypeus obliquely inclined, not perpendicular to the conspicuously convex upper surface of head. Vertex without a pair of median teeth. Occiput distinctly truncate, immarginate above. Checks submarginate with a vestigial carina below the eyes reaching back to the occipital corner. Upper surface of head smooth, very finely punctate, sparsely covered with very small, vestigial foveolae, not containing a distinctly visible hair. Hair more apparent on lower surface of head.

Thorax subfulgid to subopaque. Pronotum greatly expanded laterad, the anterior border conspicuously arcuate, the anterior corner angulate and subspinose, the lateral border not crested, the sides converging caudad. Promesonotum, in profile, greatly convex, pronotum without a distinct transverse crest or margination. Promesonotal suture vestigial. Mesonotum with a strong, apically rounded, lateral, lobe-like tooth. Mesoepinotal suture impressed, scarcely arcuate caudad. Basal face of epinotum rounded anteriorly the sides immarginate, subparallel, without a tooth, the posterior corner with a strong, rather short, slightly divergent and slightly upturned spine, the basal face being somewhat impressed above, in front of the base of each spine. Posterior border of basal face scarcely emarginate, but marginate. Dorsum of thorax and laterotergite of pronotum microscopically punctate, with sparse, more or less obsolete foveolae. Mesopleura and metapleura very finely, superficially reticulate with a few scattered scale-like hairs. Declivous face smooth, fulgid, superficially and very finely reticulate.

Petiole with smooth anterior truncate face, immarginate above mesad, submarginate laterad. The upper face rather vestigially scaled and foveolate. The spines greatly upturned and recurved. Postpetiole as wide as petiole, the spines not upturned, rather stout, blunt at apex.

Gaster subopaque, finely reticulate-punctate, broadly subcordiform. The first gastral tergite scarcely emarginate anteriorly mesad, not distinctly crested, but marginate anterolaterad, with rather dense, scattered, minute appressed shiny setulae. Sternites subfulgid, shallowly and finely reticulate, more sparsely scaled. Erect sparse setae on the following tergites and the sternites of the gaster.

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL 6.88-7.52; HL 1.68-1.84; HW 1.98-2.12; EL 0.43-0.44; PW 1.88-2.00; PeW 1.12-1.20; PpW 1.08-1.16; HBaL 0.67; HBaW 0.36; CI 115.2-117.8; PI 105.3-106.0; PPeI 166.7-167.8; PPpI 172.4-174.1; HBaI 53 .7.

Queen

Kempf (1951) - Length 10 mm. Median head length 2.12 mm; interocular width 2.17 mm; Weber's length of thorax 3.07 mm. Black; the anterior corner of the frontal carinae, the tibiae, tarsi, sides and apical border of the gastral sclerites with rufous hues.

Head, as in soldier, fulgid, finely and shallowly punctate. Median head length subequal to interocular width. Mandibles fulgid, finely and sparsely punctured, with a projecting angle above, near the base. Frontal carinae not upturned, not prolonged above beyond the eyes. Upper surface of head greatly convex, with very sparse, larger punctures. Cheeks immarginate above and below; no carinule beneath the eyes. Ocelli light and colorless. Occiput truncate, immarginate above and below. Occipital corners bluntly rounded. Lower surface of head sparsely and more coarsely punctate-foveolate.

Thorax fulgid, its maximum length subequal to the length of the first gastral tergite. Pronotum above with a transverse blunt keel, not interrupted mesad. Sides immarginate, with a stout, short, conical scapular tooth, pointing obliquely foreward. Part of pronotum in front of the keel subvertical. Basal face of epinotum very short, transverse, its posterior border emarginate and submarginate, having a stout conical tooth on each posterior corner. Declivous face perpendicular, much longer than the basal face. Upper mesopleura greatly convex, lower mesopleura with a tooth. Upper surface of thorax very finely punctate, very sparsely and vestigially foveolate. Sides and eclivous face finely and shallowly reticulate. Femora incrassated, somewhat compressed, angulate above. Tibiae twice as broad as thick. Mid and hind basitarsi greatly broadened and flattened proximad, narrower and less compressed distad, less than twice as long as broad.

Petiole with a stout conical tooth on each side. The anterior face obliquely truncate, marginate above, twice as long as the dorsal face. Postpetiole with a stout conical tooth on each side, its dorsal face greatly convex. Both peduncular segments fulgid and smooth, the microsculpture vestigial.

Gaster elongate oval, sides moderately convex, scarcely emarginate anteriorly, the anterior corners not producted, immarginate. Subfulgid, finely but distinctly reticulate, and sparsely and more or less vestigially foveolate.

Erect pile on mandibles, and apical segments of gaster; minute decumbent setulae on legs and the first gastral tergites and sternites.

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL 10.00; HL 2.04; HW 2.24; EL 0.55; PW 2.08; PeW 1.24; PpW 1.32; HBaL 0.80; HBaW 0.46; CI 109.8; PI 107.7; PPeI 167.7; PPpI 157.6; HBaI 57.5.

Male

de Andrade and Baroni Urbani (1999) - Head, eyes included, about 1/3 broader than long; vertexal margin straight in the middle and diverging laterally into two convex angles. Vertex and ocelli slightly protuberant. Eyes convex and placed 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 border almost truncate. Mandibles short and without 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 marked scapular angles and broadening backwards. Mesonotum convex; median Mayrian carina weakly impressed. Scutellum convex, its sides converging posteriorly. Propodeum with differentiate basal and declivous faces; basal face with the sides posteriorly converging and angulate; declivous face converging posteriorly and laterally marginate.

Petiole with the anterior face truncate and with the posterior face gently sloping backwards; petiolar sides convex. Postpetiole convex dorsally; postpetiolar sides gently convex, the sole specimen available has the left side with a small medial denticle and the right side simply convex.

Gaster narrower than the mesosoma.

Sculpture. Head and pronotum reticulate and with small, sparse, very superficial foveae, denser on the vertexal angles. Mesonotum and scutellum reticulate, with deeper and larger foveae than on the vertexal angles. Propodeum reticulate and with slightly longitudinal rugosities. Mesopleurae anteriorly reticulate and with dense, superficial, small foveae, this sculpture rare on the posterior half. Posterior half of the mesopleurae and metapleurae weakly shining and with longitudinal rugosities more impressed on the lower metapleurae. Propleurae, declivous face of the propodeum, pedicel, gaster and legs reticulate, the reticulation less impressed on the legs and on the gastric sternites.

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

Colour. Head, mesosoma and pedicel dark brown, femora and gaster lighter. Remaining parts of the legs yellowish and light brown.

Note: the colour of this male may not represent the adult coloration since the sole available specimen is likely to be a freshly emerged one; the genitals have been not dissected to avoid possible damaging; the wing venation is also almost indistinguishable.

Measurements (in mm) and indices: TL 6.48; HL 0.96; HW 1.24; EL 0.49; PW 1.52; PeW 0.63; PpW 0.64; HBaL 0.72; HBaW 0.14; CI 129.2; PI 81.6; PPeI 241.3; PPpI 237.5; HBal 19.4.

Type Material

de Andrade and Baroni Urbani (1999) - Worker and soldier. Type locality: Alto Acre (Brazil). Type material: one syntype worker labelled "Brasilien, Alto Acre", in Naturhistorisches Museum Wien, Vienna (examined) and one syntype soldier also in Naturhistorisches Museum Wien, Vienna (Kempf, 1951: 199).

References

  • Brandão, C. R. F. 1991. Adendos ao catálogo abreviado das formigas da região Neotropical (Hymenoptera: Formicidae). Rev. Bras. Entomol. 35: 319-412 (page 385, Combination in Zacryptocerus)
  • 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 245, male described, page 242, Combination in Cephalotes)
  • Emery, C. 1924f [1922]. Hymenoptera. Fam. Formicidae. Subfam. Myrmicinae. [concl.]. Genera Insectorum 174C: 207-397 (page 307, Combination in Cryptocerus (Paracryptocerus))
  • Kempf, W. W. 1951. A taxonomic study on the ant tribe Cephalotini (Hymenoptera: Formicidae). Rev. Entomol. (Rio J.) 22: 1-244 (page 201, queen described; page 199, Combination in Paracryptocerus)