Cephalotes maculatus

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

Cephalotes maculatus casent0173687 profile 1.jpg

Cephalotes maculatus casent0173687 dorsal 1.jpg

Specimen labels

Synonyms

A common Cephalotes species that is widely distributed and occurs in many habitat types.

Identification

A member of the pinelii clade differing from all the other species of the clade in the worker by the maximum diameter of the eyes greater than 1/3 of the head length, in the soldier, by the flat vertex, in the soldier and in the gyne by the concolour head and pronotum. The workers and soldiers from Mexico, Guatemala, Honduras, Nicaragua and Costa Rica (in part) are larger and with denser foveae on the head than the southern representatives of the species. This geographic trend does not appear in Costa Rican specimens from Alajuela, Orotina, Turrialba and Hamburg Farm. (de Andrade and Baroni Urbani 1999)

Keys including this Species

Distribution

Mexico, Guatemala, Honduras, Nicaragua, Costa Rica, Panama, Colombia, Trinidad, Guyana, French Guiana, Brazil, Ecuador, Peru, Bolivia, Argentina and Paraguay.

Distribution based on Regional Taxon Lists

Neotropical Region: Argentina, Bolivia, Brazil (type locality), Colombia, Costa Rica, Ecuador, Guatemala, Guyana, Honduras, Mexico, Nicaragua, Panama, Paraguay, Peru, Trinidad and Tobago, Venezuela.


Distribution based on AntMaps

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Distribution based on AntWeb specimens

Check data from AntWeb

Biology

Longino found a colony in a one day old treefall in Corcovado National Park: A nest was in the center of a live stem, stem dia. 14mm, at the very top of the tree. A single round hole extended perpendicularly from the surface to a central cavity which extended in both directions. The cavity was 5.5cm long and 3mm wide. The nest contained only a major, one mature worker, one callow worker, and 7 individual brood, ranging from a very small larva to a pupa.

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

Worker

Soldier

Male

Nomenclature

The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.

  • maculatus. Cryptocerus maculatus Smith, F. 1876d: 607, pl. 11, fig. 6 (q.) BRAZIL. Emery, 1894c: 208 (s.w.); Forel, 1905b: 158 (m.); Wheeler, G.C. & Wheeler, J. 1954b: 156 (l.). Combination in Paracryptocerus (Harnedia): Kempf, 1952: 18; in Zacryptocerus: Hespenheide, 1986: 395; in Cephalotes: De Andrade & Baroni Urbani, 1999: 375. Senior synonym of nanus and material of the nomen nudum cearensis referred here: Kempf, 1952: 19; of magdalenensis: De Andrade & Baroni Urbani, 1999: 375. See also: Forel, 1911e: 258; Menozzi, 1927d: 336.
  • magdalenensis. Cryptocerus grandinosus r. magdalenensis Forel, 1899b: 303 (w.) COLOMBIA. [Also described as new by Forel, 1899d: 275.] Junior synonym of grandinosus: Kempf, 1952: 11; of maculatus: De Andrade & Baroni Urbani, 1999: 337.
  • nanus. Cryptocerus maculatus r. nanus Forel, 1912e: 202 (w.) TRINIDAD. Junior synonym of maculatus: Kempf, 1952: 19.

Description

Worker

Kempf (1952) - Length 2.6-3.0 mm. Fuscous reddish-brown to black. Outer face of tibiae pale brown. Rest of legs ferruginous. Frontal carinae and membranaceous borders of thorax, peduncle and gaster whitish.

Head subquadrate, longer than wide, the median head length as long as, or longer than, the interocular width. Edge of lateral border smooth. Sides of head slightly convex and upturned above eyes. Occipital corner little or not membranaceous, sharply angulate to subdentate. Occipital border straight. Greatest diameter of eyes almost one third of maximum head length.

Thorax longer than wide. Membranaceous border of pronotum and epinotum broad, not forming a reentrant angle at the mesonotum. Shoulders subacutely angulate. Sides of mesonotum with a small projecting tooth, the tip of which is often membranaceous. Mesoepinotal suture distinct. Declivous face of epinotum differentiated from the basal face. Dorsum of hind femora longitudinally marginate, not crested, on the apical half; no crest on the lower face.

Peduncular segments subequal in width to the width of the cpinotum, with conspicuous lateral membranaceous appendages. Anterior face of petiole usually notched mesally.

Gaster longer than wide, proportionally shorter than in pinclii and grandinosus. Anterolateral membranaceous border rounded.

Subopaque, finely shagreened. Dorsum of head, thorax and peduncle with small squamiferous foveolae. Dorsum of thorax, especially on the region of the mesoepinotal suture usually with distinct longitudinal rugosities. Sides of thorax, except the laterotergite of the pronotum, and the declivous face longitudinally striated. Scale-like hair small, shiny, appressed. No erect setae on the first gastral tergite."

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL 2.81-3.93; HL 0.70-0.92; HW 0.78-1.00; EL 0.25-0.31; PW 0.72-0.96; PeW 0.50-0.59; PpW 0.48-0.56; HBaL 0.18-0.26; HBaW 0.06-0.09; CI 108.7-111.4; PI 104.2-108.3; PPeI 144.0-162.7; PPpI 150.0-171.4; HBaI 33.3-34.6.

Soldier

Kempf (1952) - Length 3.9-4.2 mm. Color as in worker. Head disc uniformly fuscous reddish-brown to black, the portion overlying the antennal scrobe not membranaceous nor differently colored. First gastral tergite, especially in larger specimens, with lighter yellowish-brown spots, one toward each corner, the anterior pair often fusing mesally into a transverse band, the posterior pair usually small, somewhat removed from the posterior border.

Head slightly longer than wide; disc not well rounded, subrectangular, excavate, flat to scarcely convex mesally. Supramandibular excision subsemicircular. Border of disc not glassy nor membranaceous. Occipital border of cephalic disc usually straight and without a pair of small, projecting denticules. Sides of head continuous with the truncate occiput, not separated by a margination or ridge.

Thorax as long as wide across the pronotum. Anterior border of pronotum broadly excised laterad, the shoulders acute and spine-like. Transverse pronotal carina slightly interrupted mesally. Mesonotum much narrower than pronotum, with a projecting, usually angulate lobe on each side. Basal face of epinotum with a small rounded lobe laterally and an upturned tubercular tooth on each posterior corner. Sides of declivous face narrowly crested. Hind femora without a dorsal and ventral crest on the apical half.

Peduncular segments as in worker; the lateral membranaceous appendages less prominent.

Gaster elliptical. The anterolateral lobes rounded, the crests lacking in large soldiers.

Integument opaque, finely shagreened. Head disc coarsely and densely foveolate. The foveolae are much smaller on the dorsum of the thorax and the peduncular segments. Gaster and sides of thorax without any conspicuous foveolae. Scales as in worker, absent on the declivous face.

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL 3.76-4.86; HL 0.96-1.20; HW 1.04-1.28; EL 0.28-0.30; PW 1.04-1.32; PeW 0.51-0.64; PpW 0.51-0.68; HBaL 0.24-0.28; HBaW 0.08-0.10; CI 106.7-108.3; PI 97.0-100.0; PPeI 203.9-206.2; PPpI 194.1-203.9; HBaI 33.3-35.7.

Queen

Kempf (1952) - Length 5.6-6.4 mm. Color as in soldier. The four maculae of the first gastral tergite better delimited and usually more prominent than in soldier, yellowish to ferruginous-yellow.

Head elongate, one and one fourth times as long as wide. Supramandibular excision narrow, subsemicircular. Cephalic disc elongate, subrectangular, moderately convex, slightly excavated, but not membranaceous, above the antennal scrobe; the sides subparallel, scarcely curved, often somewhat converging caudad; the edges of the disc scarcely crenulate, very little upturned, forming only a slightly prominent ridge postero-laterally above the occipital lobes.

Thorax elongate. Anterior border of pronotum somewhat excised laterally, not quite as prominent as in soldier. Shoulders acute. Transverse pronotal carina ininterrupted. Lower plate of mesopleura anteriorly with a tooth. Basal face of epinotum with a rounded lateral lobe and a rather sharp tooth on the posterior corner. Hind femora neither crested nor angulate above near the middle.

Peduncular segments massive, with the lateral projections scarcely membranaceous. Petiole with a lateral small tooth, pointing obliquely caudad, the postpctiole with a lateral obliquely truncate lobe, similar to that of soldier.

Gaster with the anterior border deeply emarginate, the anterolateral lobes rounded to subangulate.

Sculpture and pilosity as in soldier. The scales of the gaster are glistening and minute.

Wings hyaline. The venation of the fore wing of the usual pattern: a close and appendiculate marginal cell; transverse cubital vein present.

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL 5.64-6.84; HL 1.20-1.28; HW 1.08-1.22; EL 0.29-0.32; PW 1.06-1.14; PeW 0.44-0.51; PpW 0.60-0.68; HBaL 0.33-0.35; HBaW 0.10-0.11; CI 90.0-95.3; PI 101.9-107.0; PPeI 223.5-240.9; PPpI 167.6-176.7; HBaI 30.3-31.4.

Male

de Andrade and Baroni Urbani (1999), translation of the description of Menozzi (1927) - "Black, antennae, tibiae and tarsi ferruginous. Abundant pilosity over the whole body; pubescence limited to the antennae, tibiae and tarsi. Head much wider than long, opaque, striate-punctate, except a transversal part between the eye and the frontal lamina, smooth and shining. Mandibles small, finely punctate, with the masticatory border armed with several very small teeth. Clypeus equally very small and strongly convex posteriorly. Antennae with very short scape; the first funicular joint one third of the second in length, the latter being the longest; the last joints twice as long as broad, and, beginning from the tenth, they broaden gradually up to the last, forming a club. Thorax with pronotum and mesonotum sculptured as the head but the striae constitute the dominant pattern, particularly on their sides; scutellum simply punctate or, rarely, with two or three striae; metanotum and epinotum with visible rugae more or less curved on the dorsum, markedly straight on the sides. Mesonotum with deep Mayrian furrows. Basal face of the epinotum as long as the declivous one to which it is joined by an obtuse angle.

Petiole punctate, subquadrate and slightly marginate on the sides; postpetiole nearly shining, finely reticulate, slightly larger than the petiolar node, equally marginate on the sides which bear two small tubercles anteriorly. Gaster with sculpture similar to the one of the postpetiole, with the basal segment pyriform and occupying more than half of the whole gaster. Genitalia testaceous, with stipes broad and distally hairy; volsella terminating in a long hook with the lacinia built as a short lobe, partly concealed by the volsella itself. Wings hyaline with iridescent reflexes; pterostigma and veins testaceous; one cubital and one closed, not appendiculate radial cell, at least in the six males available to me. Length 5.2-5.8 mm.

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL 3.31-4.41; HL 0.54-0.65; HW 0.67-0.82; EL 0.31-0.38; PW 0.54-0.68; PeW 0.27-0.33; PpW 0.25-0.32; HBaL 0.29-0.31; HBaW 0.05-0.06; CI 124.1-126.1; PI 120.6-124.1; PPeI 200.0-206.1; PPpI 212.5-216.0; HBaI 17.2-20.0.

Type Material

de Andrade and Baroni Urbani (1999):

Gyne. Type locality: Salvador (Bahia, Brazil). Type material: Holotype gyne labelled "Bahia" in The Natural History Museum, examined.

Cryptocerus grandinosis magdalenensis. Worker. Type locality: Colombia (San Pablo, Magdalena R., specified by Forel, 1899 c: 275). Type material: holotype worker labelled "Cr. grandinosus r. magdalenensis, For., type, San Pablo and Magdalena, Colombie”, in Zoologische Staatssammlung, Munich (examined).

Cryptocerus maculatus nanus. Worker. Type locality: Trinidad (savannah). Type material: 1 worker labelled: "Cr. maculatus Sm., R. nanus, type Forel, Savanne, Trinidad (Forel)", in Musee d'Histoire Naturelle Genève, 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 375, Combination in Cephalotes, page 375, Senior synonym of magdalenensis)
  • Emery, C. 1894d. Studi sulle formiche della fauna neotropica. VI-XVI. Bull. Soc. Entomol. Ital. 26: 137-241 (page 208, soldier, worker described)
  • Forel, A. 1905e. Miscellanea myrmécologiques II (1905). Ann. Soc. Entomol. Belg. 49: 155-185 (page 158, male described)
  • Forel, A. 1911g. Die Ameisen des K. Zoologischen Museums in München. Sitzungsber. Math.-Phys. Kl. K. Bayer. Akad. Wiss. Münch. 11: 249-303 (page 258, see also)
  • 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. 1952. A synopsis of the pinelii-complex in the genus Paracryptocerus (Hym. Formicidae). Stud. Entomol. 1: 1-30 (page 18, Combination in Paracryptocerus (Harnedia); page 19, Senior synonym of nanus, and material of the unavailable name cearensis referred here.)
  • Menozzi, C. 1927d. Formiche raccolte dal Sig. H. Schmidt nei dintorni di San José di Costa Rica (Schluss). Entomol. Mitt. 16: 336-345 (page 336, see also)
  • 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 607, pl. 11, fig. 6 queen described)
  • Wheeler, G. C.; Wheeler, J. 1954b. The ant larvae of the myrmicine tribes Cataulacini and Cephalotini. J. Wash. Acad. Sci. 44: 149-157 (page 156, larva described)