Cephalotes serraticeps

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Cephalotes serraticeps
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Cephalotes
Species: C. serraticeps
Binomial name
Cephalotes serraticeps
(Smith, F., 1858)

Cephalotes serraticeps P casent0900230.jpg

Cephalotes serraticeps D casent0900230.jpg

Specimen Label

Specimens have been collected from wet forest.

Identification

A member of the atratus clade characterised in the worker, soldier and gyne by the autapomorphic laterally compressed and distally much narrower first tarsomeres of the mid and hind legs; from the sister species Cephalotes alfaroi, in addition, it can be separated by the strongly crenulate frontal carinae. (de Andrade and Baroni Urbani 1999)

Keys including this Species

Distribution

Distribution based on Regional Taxon Lists

Neotropical Region: Brazil (type locality), Colombia, 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.

  • serraticeps. Cryptocerus serraticeps Smith, F. 1858b: 188, pl. 11, fig. 7 (q.) BRAZIL. Wheeler, G.C. & Wheeler, J. 1983: 607 (l.); De Andrade & Baroni Urbani, 1999: 133 (s.w.q.m.). Combination in Eucryptocerus: Kempf, 1951: 132; in Cephalotes: Kempf, 1963c: 437.

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 subquadrate. Frontal carinae crenulate, diverging backwards, not covering the cheeks posteriorly and ending behind the eyes. Vertexal margin laterally carinate and medially prolonged backwards in a "neck"; vertexal angles with two pairs of spines, the internal pair narrower than the external one. Antennal scrobes over the eyes, surpassing their posterior border. Eyes globose. Postoccipital suture open antero-ventrally. Cheeks ventrally marginate. Mandibles massive and with a superficial tumulus.

Mesosoma flat and sloping posteriorly. Scapular angles anteriorly prominent. Humeral angles with a pair of long, thick spines directed upwards; tip of the pronotal spines bispinose, the anterior arm directed forwards, ca. half as long as the posterior one, directed backwards. Pronotal dorsum with a thick, transversal carina converging medially to a longitudinal, anterior one. Promesonotal suture impressed laterally only. Mesonotum unarmed, converging posteriorly. Propodeal suture impressed. Propodeum with differentiated basal and declivous faces and bearing a pair of thick, long, diverging spines directed upwards; deelivous face straight and with little converging sides.

Petiole with differentiated anterior and superior faces; anterior face truncate; superior face angular in side view, with a pair of spines at the edge. Petiolar sides almost parallel and unarmed. Postpetiole broader and shorter than the petiole, slightly convex, its dorsum with a pair of pointed spines anteriorly. Postpetiolar sides convex anteriorly and converging posteriorly.

Gaster oval, with a pair of well developed anterolateral lamellae almost reaching the stigma but surpassing the latter in form of a thin carina only.

Mid and hind femora neither angulate nor denticulate; their dorsum with a pair of longitudinal carinae more impressed on their distal half. Mid and hind tibiae laterally compressed and with a pair of well impressed longitudinal carinae dorsally. Mid and hind basitarsi strongly compressed and very broad in lateral view; their dorsum, in profile, makes an obtuse angle before the articulation with the second tarsomere.

Sculpture. Head dorsum reticulate, with superimposed, superficial, small, sparse foveae, and with irregular, thin rugosities on its posterior fourth. Frontal carinae much more superficially reticulate ncar the frons. Ventral face of the head and checks with the same sculpture as on the posterior fourth of the head dorsum but with more longitudinal rugosities. Marginal part of the antennal scrobes with transversal rugosities. Mesosoma and pedicel reticulate and with irregular foveae separated by thin, longitudinal rugosities, less marked on the pedicel. Gaster and legs reticulate, the reticulation less impressed and the integument more shining on the centre of the first gastral sternite and on the basitarsi.

Pilosity. Body with three types of hairs: (1) appressed and thin originating from each fovea; (2) hair similar to the type (1) but thinner on the legs and on the gaster; (3) erect to suberect, thick, of variable length and surrounding the frontal carinae, sparser on the ventral face of the head, on the vertexal and pronotal spines, on the legs and on the apex of the gaster, rare on the mesosoma and pedicel; (4) long, erect, truncate on the apex of the gaster and on the coxae.

Colour. Black; frontal carinae, tarsomeres and anterolateral lamellae of the first gastral tergite reddish-brown.

Measurements (in mm) and indices: TL 7.56-8.92; HL 1.60-1.84; HW 2 .04-2.28; EL 0.45-0.54; PW 1.84-2.16; PeW 0.44-0.50; PpW 0.60-0.61; HBaL 1.28-1.52; HBaW 0.34-0.41; CI 123.9.-127.5; PI 105.5-110.9; PPeI 418.2-432.0; PPpI 306.7-354.1; HBaI 26.6-27.0.

Soldier

de Andrade and Baroni Urbani (1999) - Differing from the worker for the following characters: head dorsum broader anteriorly than posteriorly; frontal carinae covering the cheeks, partially hiding the eyes and narrowing backwards. Vertexal angles with a broad, subtriangular tooth. Vertex with a pair of short, stout teeth. Vertexal margin deeply concave and with a short "neck". Eyes less globose.

Mesosoma. Pronotal sides with thicker and shorter spines not bifurcate at the apex. Pronotal dorsum with a pair of broad, triangular teeth.

Anterolateral lamellae of the gaster narrower.

Sculpture. Head superficially and minutely reticulate, with dense foveae on the posterior third, the foveae diminishing in size and sparser anteriorly, smaller and shallower on the frontal carinae. Ventral face of the head, mesosoma and pleurae with the same type of sculpture as on the posterior third of the head, the foveae absent on the middle of the mesopleurae and on the lower metapleurae. Peduncular segments with superficial, irregular foveae. Gaster and legs reticulate, the reticulation less impressed on the centre of the first gastral sternite and on the basitarsi. The anterior third of the first gastral tergite, in addition, is covered by superficial foveae with superimposed, superficial, longitudinal rugosities. Mid and hind femora with thin, transversal rugosities; this sculpture equally present but less impressed and oblique on the fore femora.

Pilosity. Body with four types of hairs: (1) short, appressed, thin originating from each fovea; (2) appressed and pointed on the gaster and on the legs; (3) erect to suberect, thick, slightly clavate and variable in length surrounding the head, on the mesosoma, on the peduncular segments, on the gaster and on the legs; (4) long and pointed on the two last gastral tergites and on all sternites.

Colour. Black.

Measurements (in mm) and indices: TL 11.88; HL 2.80; HW 3.32; EL 0.68; P W 2.76; PeW 0.80; PpW 0.84; HBaL 1.84; HBaW 0.52; CI 118.6; PI 120.3; PPeI 345.0; PPpI 328.6; HBaI 28.3.

Queen

de Andrade and Baroni Urbani (1999) - Head longer than broad and without disc. Vertex with a pair of subround teeth. Vertexal angles with a small subtriangular tooth. Frontal carinae with parallel sides, distinctly crenulate over their whole length; the denticles constituting the crenulation well marked and spaced. Pair ocelli obsolete and confused with the microsculpture. Eyes moderately protruding laterally.

Mesosoma, in profile, raised and flat at the height of the mesonotum. In dorsal view the sides subparallel up to the propodeum - which is much narrower - moderately bulging at the level of the alar sclerites. Pronotum abruptly sloping cranially. Scapular angles distinct, their distance shorter than the one between the pronotal spines; the latter short, pointed and obliquely directed forwards. Scutellum nearly flat, abruptly sloping caudally. Propodeum with the basal face gently sloping caudally, moderately convex and much shorter than the descending one. Descending face concave. Propodeal spines horizontal and parallel, about half as long as their distance at the apex.

Petiole sessile, with abrupt anterior face making an angle of almost 90° with the superior one. Postpetiole only slightly broader than the petiole, with short but distinct anterior face separate by a weak, marginate angle from the superior one; ventral postpetiolar tooth moderately prominent but marked. Petiole and postpetiole without lateral spines or expansions.

Gaster nearly twice longer than broad, poorly marginate anteriorly; laterally the margination docs not reach the stigma of the first segment.

Fore tibiae moderately, mid and hind tibiae strongly compressed laterally. Hind basitarsi 1 strongly compressed and very broad (more than in the aI/aroi workers) in lateral view; its dorsal side, in profile, makes an obtuse angle before the articulation with the second tarsomere.

Fore wings. Distal part of R+Sc depigmented; 2r well visible; Rsf5 connected with R1 partially outlining the distal border; A, Cu-A, Cu-A l and Mf4 well marked and reaching the distal border; cu-a interrupted in the middle.

Hind wings: R, M+CuA, lA, CuA, r-m1 and M well marked; distal parts of CuA and M vestigial and nearly reaching the distal border. Two or three additional r-m present.

Sculpture. Body largely smooth and shining, the sculpture relatively uniform, composed essentially of deep round, foveae. The foveae much denser on the head capsule and on the pedicel (their distance equal to their maximum diameter) than on the mesosoma (distance between the pits ca. twice their maximum diameter) and on the gaster where they are much less impressed, concentrated on the anterolateral portion of the first tergite and sparser (distance between the pits often three times their diameter). Posterior border of the first gastral tergite, first gastral sternite and remaining gastral segments finely reticulate-punctate with superimposed shallow foveae. Mandibles longitudinally striate. Legs and antennal scapes minutely reticulate-punctate.

Pilosity. Besides the minute foveal hairs, the pilosity consists of long, clavate hairs around the antennal scrobes (more clearly clavate than in alfaroi). Similar clavate hairs on the sides of the mesosoma and on the scutellum. A few truncate or pointed hairs on the propodeum. Pedicel and dorsal face of the gaster with truncate, subtruncate, or pointed sparse hairs. Sparse, acuminate hairs on the first gastral tergite. Distal half of the first dorsally and remaining gastral sternites wholly with long, pointed hairs. Mandibles and antennae covered by thick, appressed, truncate or subtruncate hairs. Legs similarly covered by suberect to subdecumbent clavate or truncate hairs.

Colour. Black very shining over most of the body, opaque only on the lateral and posterior border of the first and on the following segments of the gaster and on the appendages where the microscopic reticulation-punctuation is present. Wings yellowish transparent with opaque brown distal part of the submarginal and of the marginal cells. Hairs golden.

Measurements (in mm) and indices: TL 15.50-16.00; HL 2.88-3 .00; HW 3.00-3.10; EL 0.68; PW 2.80; PeW 0.92-0.96; PpW 1.04-1.08; HBaL 1.80-1.84; HBaW 0.60-0.64; CI 103.3-104.2; PI 107.1-110.7; PPcI 291.7-304.3; PPpI 259.2-269.2; HBaI 33.3-34.8.

Male

de Andrade and Baroni Urbani (1999) - Head (eyes included) more than 1/3 broader than long. Vertexal angles, internally , with a short, triangular denticle and with a broad, triangular tooth close to the posterior border of the eye. Vertexal margin prolonging backwards into a broad "neck". Vertex dorsally convex and bearing salient ocelli. Compound eyes convex, in the middle of the sides of the head. Frontal carinae low, not reaching the impair ocellus. Frons flat posteriorly, slightly declivous anteriorly. Clypeus-convex posteriorly, marked by a transverse, median angle sloping anteriorly. Mandibles slender, laterally with a superficial carina. Scapes thick and short, not reaching the posterior border of the eyes.

Mesosoma. Pronotum in dorsal view anteriorly protruding, and with the sides diverging backwards. Pronotal dorsum separate from the sides by a transverse carina. Mesonotum convex in side view; Mayrian furrows impressed. Scutellum as high as the mesonotum, its sides converging posteriorly. Basal face of the propodeum much lower than the scutellum; dorsum of the basal face sloping backwards, but differentiate from the declivous one; sides of the basal face gently converging backwards, without denticles or teeth. Declivous face with converging sides, laterally and medially marked by a pair of longitudinal carinae.

Petiole with truncate anterior face; petiolar sides unarmed and gently converging posteriorly. Postpetiole broader than the petiole; postpetiolar sides bearing a round denticle in their anterior third.

Gaster with its maximum width at the posterior border of the first segment, almost three times broader than its articulation with the postpetiole.

Sculpture. Head dorsum reticulate; posterior half and sides of the head with irregular, slightly longitudinally oriented reticulate rugosities; this sculpture more superficial and the inter-reticular depressions smaller on the frons. Ventral part of the head with the same type of sculpture as on the vertexal angles and, around the eyes, with short, transversal rugosities. Pronotal dorsum, mesonotum, scutellum and basal face of the propodcum reticulate and with dense, irregular foveae with marked border. Sides of the pronotum, posteriorly, reticulate and with irregular, longitudinal rugosities. Pleurae reticulate and with longitudinal rugosities more regular on the metapleurae; lower mesopleurae with additional, irregular foveae. Declivous face of the propodeum, anterior third of the petiole and of the postpetiole reticulate and with irregular rugosities; the rugosities longitudinal on the sides of the petiole and postpetiole. First gastral tergite superficially reticulate; the same sculpture but more superficial and slightly shining on the remaining tergites, on the sternites and on the legs.

Pilosity. Body with two types of hairs: (1) flexuous, long, pointed hairs, more dense on the head and on the mesosoma, sparser on the pedicel and on the gaster; (2) shorter than the type (1) hairs, decumbent and dense on the legs, sparse on the scapes; (3) short, thin, on the antennae. Colour. Black.

Measurements (in mm) and indices: TL 10.10; HL 1.36; HW 1.68; EL 0.65; PW 1.44; PeW 0.65; PpW 0.79; CI 123.5; PI 116.7; PPeI 228.6; PPpI 182.3.

Holotype Specimen Labels

Type Material

de Andrade and Baroni Urbani (1999) - Gyne. Type locality: Ega (= Tefe), Amazonas (Brazil). Type material: Holotype gyne labelled "Cryptocerus serraticeps, Type Sm., 56 84" in The Natural History Museum (Kempf, 1964a: 437), examined.

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 133, soldier, worker, queen, male described)
  • Kempf, W. W. 1951. A taxonomic study on the ant tribe Cephalotini (Hymenoptera: Formicidae). Rev. Entomol. (Rio J.) 22: 1-244 (page 132, Combination in Eucryptocerus)
  • Kempf, W. W. 1963c. Nota sinonímica acêrca de formigas da tribo Cephalotini (Hymenoptera, Formicidae). Rev. Bras. Biol. 23: 435-438 (page 437, Combination in Cephalotes)
  • Smith, F. 1858a. Catalogue of hymenopterous insects in the collection of the British Museum. Part VI. Formicidae. London: British Museum, 216 pp. (page 188, pl. 11, fig. 7 queen described)
  • Wheeler, G. C.; Wheeler, J. 1983a. Supplementary studies on ant larvae: Myrmicinae. Trans. Am. Entomol. Soc. 108: 601-610 (page 607, larva described)