Cephalotes patei

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Cephalotes patei
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Cephalotes
Species: C. patei
Binomial name
Cephalotes patei
(Kempf, 1951)

Cephalotes patei casent0912612 p 1 high.jpg

Cephalotes patei casent0912612 d 1 high.jpg

Specimen Labels

Cephalotes patei has never collected in its natural environment. Records from the United States are from interception of individuals at plant quarantine stations.

Identification

The only member of the patei clade. Separable at glance from the members of its closest clades by the lack of vertexal denticles and, in particular, from crenaticeps and ecuadorialis by the lack of coloured spots on the gaster of all three female castes and from emeryi by the coloration, brown with lighter frontal carinae instead of uniformly black. (de Andrade and Baroni Urbani 1999)

Keys including this Species

Distribution

Known only from samples of probable Colombian origin intercepted at U. S. plant quarantine stations.

Distribution based on Regional Taxon Lists

Neotropical Region: Colombia (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.

  • patei. Paracryptocerus (Harnedia) patei Kempf, 1951: 235, figs. 151, 153-155 (s.w.q.m.) COLOMBIA. Combination in Zacryptocerus: Brandão, 1991: 387; in Cephalotes: De Andrade & Baroni Urbani, 1999: 517.

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

Description

Worker

Length 5.7 mm. Median head length 1.41 mm; Weber's length of thorax 1.63 mm. Black; the apex of the funicular segment and the three apical tarsal segments ferrugenous. Tips of mandibles fuscous-ferruginous.

Head subopaque, subquadrate; its maximum length distinctly shorter than the interocular width (65:72). Mandibles rugulose. Frontal carinae with semitransparent, more or less infuscated maculae; the lateral border vestigially crenulate, slightly sinuate and diverging behind, scarcely upturned above the eyes. Occipital angles obliquely truncate, the edges serrate or notched. Eyes small, their greatest diameter less than one fourth of the median head length. Upper surface of head scarcely but evenly convex, finely reticulate-punctate, more sparsely covered with squamiferous foveolae, which are somewhat denser and larger towards the occiput. Vertex without a pair of small denticules. Lower surface of head rather coarsely reticulate-rugose.

Thorax subopaque. Anterior border moderately arcuate. Shoulders subrectangular. Sides of pronotum with a flat, narrow rectangular projecting lamella, the apical border of which is emarginate and bidentate, the posterior border emarginate and converging towards the rectangular, subdentate posterior corner of the pronotum. Promesonotal suture vestigial. Mesonotum with a small denticule on each side. Mesoepinotal suture distinct, slightly impressed. Anterior corner of basal face of epinotum rather obtuse, not sharply rectangular, the sides with a triangular tooth. Declivous face more or less differentiated from the basal face. Dorsum of thorax finely reticulate-punctate, rather densely covered with squamiferous foveolae, the slightly raised intervals between which form a coarse reticule. A few ongitudinal rugae mesad on basal face of epinotum. Declivous face of epinotum, the laterotergite of pronotum and the greater portion of the thoracic pleura coarsely longitudinally striated. Femora not angulate above at the half. Hind basitarsi compressed and somewhat broadened basad.

Peduncolar segments subopaque, the dorsolateral sculpture as on dorsum of thorax. Petiole narrower than postpetiole, its anterior face obliquely truncate, finely reticulate-punctate, subfulgid, without macrosculpture and pilosity. Anterior corners subangulate, the sides with a small, acute tooth. Postpetiole with a slender, acute tooth, arising from the anterior corner. Upper face flat, not bordered by longitudinal ridges.

Gaster short, suboval, subopaque. Strongly convex above. Scarcely emarginate in front mesad, the anterolateral border sharply marginate and crested. Length: depth proportion less than 1.5 (75:55). First gastral tergite finely reticulate-punctate, more coarsely areolate-rugose, each areole containing a shallow squamiferous groove. Sculpture not evanescent discally.

Sides of head, excluding truncate occipital angles, sparsely beset with short, whitish, thick, projecting setulae, which are somewhat longer than those of emeryi. Upper surface of head, thorax, peduncle and gaster with oval, canaliculate scales, shorter than those of emeryi and not as aureate. Strictly silvery on the appendages and the densely scaled areas of the thoracic pleura. Apical borders of gastral tergitcs and sternites with common, sparse, erect pile.

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL 5.40-5.72; HL 1 .34-1.36; HW 1.68-1.72; EL 0.36; PW 1.52-1.60; PeW 0.56-0.64; PpW 0.68-0.72; HBaL 0.60-0.64; HBaW 0.22; CI 125.4-126.5; PI 105.0-113.1; PPeI 237.5-285.7; PPpI 222.2-235.3; HBal 34.4-36.7.

Soldier

Length 7.3 mm. Median head length 1.97 mm; Weber's length of thorax 2.10 mm. Black; the frontal carinae dark rufous brown; tip of last funicular segment and three apical tarsal segments ferruginous.

Head subopaque; surmounted by a circular, flat, completely marginate disc, with an antero-median emargination, exposing the strongly rugose mandibles from above. Anterolateral border of disc crenulate, the median portion of the posterior border strictly truncate, forming a bidentate crest above the perpendicularly truncate occiput. Floor of disc very slightly raised in the middle, just behind the vestigially outlined clypeus, and again less prominently farther behind on the vertex, very shallowly excavate laterad of the anterior convexity where the margins are slightly upturned. Occipital angles blunt, rounded, carinulate. Eyes moderately convex. Lower border of cheeks carinate. Upper surface and sides of head finely reticulate-punctate, coarsely, densely and deeply foveolate. Lower surface of head fulgid, areolate-foveolate.

Thorax subopaque. Shoulder angle scarcely visible from above. Pronotum greatly expanded on each side, the anterior angle acute and subdentate, the posterior angle bluntly rounded. Transverse pronotal crest strong and greatly raised, narrowly interrupted in the middle by a cut-like longitudinal incision. Promesonotal suture distinct. Sides of mesonotum bluntly rounded, the posterior border bisinuate, followed by a deeply impressed metanotal groove. Basal face of epinotum conspicuously transversely convex, with a short broad tooth on the sides and another similar tooth on the posterior corners. Declivous face more than twice as long as the basal face, immarginate laterad. Sculpture as on upper surface of head, the squamiferous foveolae more crowded and smaller. Sides of the thorax coarsely rugose. Legs as in worker. Peduncular segments and gaster similar to those of the worker; the postpetiole and petiole narrower.

Rim of projecting setulae extending around the disc to the posterior border of the eyes. Scales within the foveolae oval, canaliculate, as in worker.

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL 7.60-7.72; HL 2.00; HW 2.32; EL 0.40; PW 2.20-2.28; PeW 0.72-0.76; PpW 0.76-0.80; HBaL 0.72; HBaW 0.26; CI 116.0; PI 101.7-105.5; PPeI 300.0-305.5; PPpl 285.0-289.5; HBal 36.1.

Queen

Length 8.2 mm. Median head length 1.97 mm; Weber's length of thorax 2.39 mm. Resernbling the soldier in color, sculpture pilosity and general structure, with the exception of the peculiarities of the caste and the following details:

Head disc still flatter, the postero-lateral border only faintly marginate, the posterior portion behind the deeply sunken ocelli slightly curved downwards. The posterior border crested as in the soldier. Shoulders obsolete. Transverse pronotal crest distinct, not as strong nor as highly raised as in the soldier, the median interruption broader, not slit-like. The anterior tip of the lateral expansion of the pronotum forming an acute large, triangular tooth. Scutellum longitudinally convex. Basal face of epinotum very short, the lateral and posterior teeth more obtuse. Lower mesopleura with a strong tooth. First gastral tergite longer than the maximum length of the thorax (118:98). Gaster somewhat longer than in soldier. Wings hyaline, the veins brunneus, the stigma fuscous. Fore wing with a closed and appendiculate marginal cell and a transverse cubital vein. The second abscissa of the median vein not much longer than the transverse median vein.

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL 8.96-9.12; HL 2.00-2.04; HW 2.24-2.30; EL 0.41; PW 2.12-2.16; PeW 0.68; PpW 0.77-0.79; HBaL 0.76; HBaW 0.29; CI 112.0-112.7; PI 108.5-108.7; PPeI 331.8-317.6; PPpI 269.3-280.5; HBaI 38.1.

Male

Length 6.4 mm. Median head length 0.9 mm; Weber's length of thorax 2.19 mm. Black; the tip of mandibles, antennae, legs and gaster brunneous.

Head subopaque; transverse. Distance between the eyes longer than the median head length (49:39). Mandibles finely and densely punctate, somewhat rugulose at apex. Chewing border with a strong apical and postapical tooth, and three following minute teeth. Clypeus convex, with a transverse incision, near the posterior border. Front slightly impressed in front of the anterior ocellus. Eyes large, their maximum diameter slightly less than half of the median head length (18:39). Ocelli raised on short sockets. A vestigial crest extending from behind the eye to the bluntly rounded, yet visible occipital angle. Integument finely reticulate-punctate and rugose, the rugae being transverse between the eyes and the rather smooth front, forming a network between the cheeks, the occiput and the lower surface of the head. Scape and first antennal segment glabrous. Length of scape about one half of the second funicular segment.

Thorax subopaque, somewhat similar to that of the female. Pronotum with similarly projecting anterolateral, apically pointed, lobes on each side. Transverse crest inconspicuous, obsolescent towards the sides, ininterrupted mesad. Mayrian furrows deeply impressed in scutum. Epinotum unarmed. Sculpture as on head. The posterior portion of the sides and the epinotum with highly raised, undulating ridges, longitudinal on the sides, more or less transverse on the basal face of the epinotum.

Petiole about as long as wide, anterior face obliquely truncate, sides unarmed. Dorsal and lateral face covered with a network of raised ridges. Postpetiole slightly broader than petiole, with a tubercular tooth on each side, somewhat in front of the half. Sculpture as on petiole, ridges less conspicuous and predominantly longitudinal in direction.

Gaster subfulgid, very finely reticulate. First gastral tergite without erect pile. Head and thorax with abundant, long, flexuose, whitish and erect pile. A thin brush of similar hairs arising from beneath the postpetiole. Setae shorter, stiffer sparser and suberect on the remaining tergites of the gaster and on the sternites. Legs with similar pile, which is sparse and subdecumbent.

Wings short, scarcely projecting beyond the tip of the gaster when folded, hyaline, the veins pale brunneous, the stigma darker. Venation similar to that of female. Second abscissa of median vein subequal in length to the transverse median vein .

Type Material

de Andrade and Baroni Urbani (1999) - Worker, soldier, gyne, male. Type locality: intercepted in New Jersey on Cattleya (orchids) imported from Colombia. Type material: holotype worker in the U. S. National Museum, not available for the present study; paratypes numerous workers, soldiers, gynes and one male in Museu de Zoologia da Universidade de Sao Paulo, Museum of Comparative Zoology and National Museum of Natural History (examined in part).

References

  • Brandão, C. R. F. 1991. Adendos ao catálogo abreviado das formigas da região Neotropical (Hymenoptera: Formicidae). Rev. Bras. Entomol. 35: 319-412 (page 387, 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 517, Combination in Cephalotes)
  • Kempf, W. W. 1951. A taxonomic study on the ant tribe Cephalotini (Hymenoptera: Formicidae). Rev. Entomol. (Rio J.) 22: 1-244 (page 235, figs. 151, 153-155 soldier, worker, queen, male described)