Cephalotes duckei

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Cephalotes duckei
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Cephalotes
Species: C. duckei
Binomial name
Cephalotes duckei
(Forel, 1906)

Cephalotes duckei casent0909262 p 1 high.jpg

Cephalotes duckei casent0909262 d 1 high.jpg

Specimen Labels

Nothing is known about the biology of Cephalotes duckei.

Identification

A member of the laminatus clade differing from all the other species of the clade in the worker and in the soldier by the rectangular pronotal lamellae and the angulate hind femora, and in the soldier and in the gyne by the presence of an incomplete disc. (de Andrade and Baroni Urbani 1999)

Keys including this Species

Distribution

Known from Colombia and Brazil.

Distribution based on Regional Taxon Lists

Neotropical Region: Brazil (type locality), Colombia.

Distribution based on AntMaps

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Distribution based on AntWeb specimens

Check data from AntWeb

Abundance

This species appears to be rare in the collections, even in those from intensely collected areas, like the Reserva Ducke in Amazonas.

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.

  • duckei. Cryptocerus duckei Forel, 1906d: 233, fig. 1 (w.) BRAZIL. De Andrade & Baroni Urbani, 1999: 189 (q.m.). Combination in Cryptocerus (Paracryptocerus): Emery, 1924d: 307; in Paracryptocerus: Kempf, 1951: 231; in Zacryptocerus: Kempf, 1974a: 69; in Cephalotes: Baroni Urbani, 1998: 326; De Andrade & Baroni Urbani, 1999: 186. See also: Kempf, 1967e: 363.

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

Description

Worker

Kempf (1974) - Total length 3.7-4.3 mm; head length 1.11-1.28 mm; interocular width (distance between the inner borders of the eyes across the head) 1.13-1.35 mm; maximum diameter of eyes 0.27-0.30 mm; Weber's length of thorax 0.97-1.10 mm; pronotum width (projecting flange included) 1.03-1.19 mm; petiole width 0.45-0.54 mm; postpetiole width 0.39-0.54; gaster width 1.37-1.51 mm. Exactly like the types (aborted soldiers) with the following differences: Head slightly narrower but still broader than long; occipital flanges more projecting and semidiaphanous. Scapular corners acute. Lateral projection of pronotum apically bidentate, foliaceous and semidiaphanous. Transverse pronotal carina absent (the large specimens of the series already have vestiges of a transverse carina in the form of a pair of minute denticles on pronotum). Tips of propodeal, petiolar and postpetiolar spines likewise depigmented and light in color.

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL 3.84-4.60; HL 0.95-1.08; HW 1.28-1.48; EL 0.28-0.30; PW 1.04-1.20; PeW 0.49-0.56; PpW 0.45-0.50; HBaL 0.3 6-0.44; HBaW 0.11-0.13; Cl 134.7-137.0; PI 123.1-123.3; PPeI 212.2-214.3; PPpI 231.1-240.0; HBaI 29.5-30.5.

Soldier

de Andrade and Baroni Urbani (1999) - Head feebly convex. Frontal carinae converging before the eyes and prolonging behind the eyes as a margin. Vertexal angles obtuse. Vertex with a pair of median short teeth connected each other by a median carina continuing laterally to join the frontal carinae. Mandibles broad, with a small lateral tumulus.

Mesosoma. Scapular angles short. Humeral angles with a broad lateral lamella, with pointed anterior border followed by a concavity and a subround, obtuse tooth, and posteriorly converging sides. Pronotal carina wide, interrupted in the middle by a deep notch. Promesonotal suture impressed on the sides. Mesonotum with a broad, rounded tooth. Propodeal suture deeply impressed. Propodeum clearly differentiated in basal and dcclivous faces. Basal face with three pairs of teeth; the anterior one, small, broad and subtriangular, the median one small and high, and the posterior pair broad, subpointed, lamellaceous and converging towards the declivous face.

Petiole with the anterior border slightly concave; petiolar spines directed backwards and with round tips. Postpetiolar spines as in the petiole, but originating on the anterior face of the postpetiole and curved laterally.

Gaster oval, with a broad lamellaceous border reaching the stigma and continuing backwards as a thin margin.

Legs. Fore coxae with a broad lobe anteriorly. Mid and hind femora forming an angle without denticles. Hind basitarsi flat and broad at the base.

Sculpture. Head dorsum minutely reticulate-punctate and covered by faint, small oval foveae with their interspaces larger than maximum fovea diameter; this sculpture more superficial on the frontal carinae. Vertexal area behind the head disc, ventral part of the head, mesosoma and pedicel reticulate-punctate and foveolate, the foveae larger and deeper than those on the head dorsum, shallower on the basal face of the propodeum and on the pedicel, sparser on the propleurae. Declivous face of the propodeum, meso- and metapleura, legs and gaster reticulate-punctate. Posterior half of the first gastral sternite centrally faintly reticulate-punctate, almost shining.

Pilosity. Each fovea bears a thick, appressed, canaliculate hair; gaster and legs with sparse hairs, thinner than those on the pronotum. Mandibles, legs and posterior part of gaster with slightly clavate, suberect hairs, longer on the gaster. Cheeks without appressed hairs.

Colour. Head, mesosoma and basitarsi dark brown. Frontal carinae, pedicel and legs ferrugineous.

Gaster reddish to light brown.

Measurements (in mm) and indices: TL 6.24-6.72; HL 1.48-1.64; HW 2.00-2.08; EL 0.40; PW 1.88-2.04; PeW 0.73-0.80; PpW 0.70-0.72; HBaL 0.56-0.60; HBaW 0.20; CI 126.8-135.1; PI 101.9-106.4; PPeI 255.0-257.5; PPpI 268.6-2 83.3; HBaI 33.3-35.7.

Queen

de Andrade and Baroni Urbani (1999) - Head with traces of disc, dorsally convex. Frontal carinae convex anteriorly; their sides converging in front of and ending behind the eyes. Vertexal angles round. Vertex with a pair of median teeth connected each other by a median carina continuing laterally to junction of the mandibles.

Mesosoma. Humeral angles with a pointed anterior tooth. Pronotal crest narrow and superficially interrupted in the middle. Mesonotum and scutellum flat. Lower mesopleura with a small denticle.

Basal face of propodeum with two broad and round teeth, the anterior smaller than the posterior ones, the latter between the basal and declivous faces; declivous face concave. Petiole with the anterior border slightly concave and oblique; petiolar sides convex, without spines. Postpetiole broadly convex; anterior sides of the postpetiole with a small, obtuse tooth or unarmed.

Gaster with a broad anterior lobe.

Legs. Fore coxae with a broad lobe anteriorly. Mid and hind femora not angulate. Hind basi tarsi flat and slightly broadened at their base.

Wings. Fore wings with R+Sc superficially connected with a marked pterostigma. 2r marked, Rsf5 connected with R1. Distal parts of A, Cu-A1 and Mf4 vestigial. Hind wings with R, M+ CuA, M and 1A marked; CuA, M and distal part of 1A vestigial.

Sculpture. Head minutely reticulate-punctate and covered by faint, small foveae with their interspaces larger than their maximum diameter. Frontal carinae with foveae sparser than those on the head and superficially reticulate-punctate almost shining. Occipital area behind the head disc, ventral part of the head, mesosoma, pedicel reticulate-punctate and with foveae larger and deeper than those on the head dorsum; the foveae sparser on the anterior half of the propleurae and on the middle of the mesopleurae and on the pedicel dorsum, denser, deeper on the propodeum, over the metapleural gland. Concavity of the declivous face of the propodeum, anterior third of the mesoplcurae, area under the metapleural gland, legs and gaster reticulate-punctate. Shallower reticulation on the legs and on the gaster, slightly shining. First gastral sternite faintly reticulatc-punctated almost shining, centrally and posteriorly.

Pilosity. Each fovea bears a thick, appressed, canaliculate hair; mandibles, mesosoma, pedicel and legs with rare, slightly clavate, suberect hairs, longer and sparser on the apex of the gaster. Legs and gastral sternites with sparse and thinner hairs than those on the foveae.

Colour. Head, mesosoma, pedicel and basitarsi dark brown, frontal carinae and legs lighter. Gaster reddish to light brown, with two pairs of yellow spots, one on the gastral lobes and the other pair on the posterior sides of the first gastral tergite.

Measurements (in mm) and indices: TL 11.04-11.36; HL 2.04-2.12; HW 2.36; EL 0.44-0.48; PW 2.28-2.32; PeW 0.96-1.00; PpW 0.88-1.00; HBaL 0.72-0.75; HBaW 0.26-0.28; CI 113.2-115.7; PI 103.4-105.3; PPeI 228.0-241.6; PPpI 228.0-272.7; HBaI 34 .6-38.8.

Male

de Andrade and Baroni Urbani (1999) - Head (eyes inc!uded) 1/3 broader than long; sides of the head convex, converging to the straight vertexal margin. Vertex dorsally protruding, bearing salient ocelli. Compound eyes broadly convex, in the middle of the sides of the head. Frontal carinae diverging backwards, not reaching the median ocellus posteriorly. Frons flat. Clypeus slightly convex; its posterior border marked by a convex carina; its anterior border with a median concavity between a pair of small dentic!es absent in some specimens. Mandibles slim, with a pointed apical tooth followed by 4-5 minute denticles; external face without carina. Scapes thick, twice as long as the first funicular joint; remaining funicular joints filiform and thickening from the base to the apex.

Mesosoma. Pronotum in dorsal view with the sides diverging backwards, without carinae. Mesonotal scutum convex in side view; median Mayrian furrow little impressed. Scutellum convex, its sides converging posteriorly. Basal and declivous faces of the propodeum poorly differentiated; basal face little sloping and convex; declivous face shorter than the basal one and almost straight. Propodeal sides marked by a longitudinal, convergent carina.

Petiole narrower than the postpetiole. Anterior face of the petiole oblique and medially concave; posterior face flat. Petiolar sides convex anteriorly, converging posteriorly. Postpetiole little convex dorsally; its sides with a subround tooth.

Gaster as broad as the mesosoma.

Wings. As in the gyne.

Sculpture. Head dorsum reticulate, irregularly rugulose, with dense foveae on the vertexal border and sparse foveae on the frons. Ventral face of the head, lower mesopleurae, upper metapleurae, basal face and anterior half of the declivous faces of the propodeum, and sides of the petiole longitudinally rugulose. Mesonotum, scutellum, propleurae and upper mesopleurae superficially reticulate-foveolate. Postpetiole, first gastral tergite and sternite reticulate, remaining gastral segments and legs superficially reticulate and slightly shining.

Pilosity. Body with three types of hairs: (1) flexuous, long, thin, pointed hairs dense on the head, the mesosoma, the pedicel and the legs, slightly sparser on the gaster; (2) shorter than the cephalic hairs, decumbent, dense on the anterior border of the pronotum and on the dorsum of the petiole, and sparser on the outer face of the femora and on the postpetiolar dorsum; (3) short, appressed and suberect on the funiculi.

Colour. Head, mesosoma, pedicel and coxae dark brown to black; antennae lighter. Gaster, legs and wings yellow to light brown, wings slightly infuscated; tarsi reddish brown. Body hairs golden.

Measurements (in mm) and indices (based on two specimens from Reserva La Macarena, Meta, Colombia): TL 9.24-9.56; HL 1.08-1.16; HW 1.48; EL 0.48-0.50; PW 1.88-2.00; PeW 0.72-0.76; PpW 0.90-0.92; HBaL 0.92; HBaW 0.16; CI 127.6-137.0; PI 74.0-78.7; PPeI 261.1-263.1; PPpI 208.8-217.4; HBaI 17.4.

Type Material

de Andrade and Baroni Urbani (1999) - Small soldier. Type locality: Barce!os (Amazonas, Brazil). Type material: lectotype and paralectotype intercastes labelled "Barcellos, 2.7.1905, A. Ducke; Cr. Duckei Forel, worker type, Rio Negro, Amazonas (Ducke); P. duckei For. uppermost soldier Lectotypus WWK", in the Musee d'Histoire Naturelle Genève (Kempf, 1 967: 363) (examined).

References

  • Baroni Urbani, C. 1998b. The number of castes in ants, where major is smaller than minor and queens wear the shield of the soldiers. Insectes Soc. 45: 315-333 (page 326, Combination in Cephalotes)
  • 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 189, queen, male described, page 186, Combination in Cephalotes)
  • Emery, C. 1924f [1922]. Hymenoptera. Fam. Formicidae. Subfam. Myrmicinae. [concl.]. Genera Insectorum 174C: 207-397 (page 307, Combination in Cryptocerus (Paracryptocerus))
  • Forel, A. 1906d. Fourmis néotropiques nouvelles ou peu connues. Ann. Soc. Entomol. Belg. 50: 225-249 (page 233, fig. 1 worker described)
  • Kempf, W. W. 1951. A taxonomic study on the ant tribe Cephalotini (Hymenoptera: Formicidae). Rev. Entomol. (Rio J.) 22: 1-244 (page 231, Combination in Paracryptocerus)
  • Kempf, W. W. 1967e. A new revisionary note on the genus Paracryptocerus Emery (Hym. Formicidae). Stud. Entomol. 10: 361-368 (page 363, see also)
  • Kempf, W. W. 1974a. Taxonomic and faunistic notes on some Neotropical Cephalotini ants (Hymenoptera, Formicidae). Rev. Bras. Entomol. 18: 67-76 (page 69, Combination in Zacryptocerus)