Cephalotes foliaceus

Every Ant Tells a Story - And Scientists Explain Their Stories Here
Jump to navigation Jump to search
Cephalotes foliaceus
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Cephalotes
Species: C. foliaceus
Binomial name
Cephalotes foliaceus
(Emery, 1906)

Cephalotes foliaceus P casent0904925.jpg

Cephalotes foliaceus D casent0904925.jpg

Specimen Label

Nothing is known about the biology of Cephalotes foliaceus.

Identification

A member of the grandinosus clade differing from all the other species of the clade in the worker and soldier by the first gastral tergite surrounded by a membranaceous border. (de Andrade and Baroni Urbani 1999)

Keys including this Species

Distribution

Panama, Colombia, Peru and Bolivia.

Distribution based on Regional Taxon Lists

Neotropical Region: Bolivia, Colombia, Panama, Peru (type locality).


Distribution based on AntMaps

AntMapLegend.png

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.

  • foliaceus. Cryptocerus foliaceus Emery, 1906c: 172 (footnote), fig. 32 (w.) PERU. Kempf, 1952: 8 (s.). Combination in Paracryptocerus (Harnedia): Kempf, 1952: 7; in Zacryptocerus: Hespenheide, 1986: 395; in Cephalotes: De Andrade & Baroni Urbani, 1999: 431.

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

Description

Worker

Kempf (1952) - Length 4.2 mm. Median head length 1.07 mm. Weber's length of thorax 1.12 mm. Yellowish-brown, the anterior portion of the first gastral tergite much paler. Membranaceous borders and frontal carinae yellowish-white.

Head longer than thorax (52:46), broader than long (59:52), convex discally above. Supramandibular excision broad, subrectangular. Borders of frontal carinae and occipital corners finely denticulate. Lateral border of head slightly concave, scarcely upturned above eyes. Occipital corners rounded and membranaceous. Greatest diameter of eyes about 1/5 of maximum head length (11:52).

Thorax, in dorsal view, subquadrate, depressed; sides parallel. Anterior corners of pronotum obtusely angulate, posterior corners rounded. Mesonotum with a broad, apically truncate, membranaceous plate on each side. Mesoepinotal suture distinct laterad, obsolete mesally. Epinotum as wide as pronotum, both with broad membranaceous border. Declivous face not differentiated from the basal face. Femora with a strong longitudinal membranaceous crest apically above and below.

Petiole slightly wider than postpetiole, not impressed anteromesally, without distinctly truncate anterior face above the thoracic insertion, the lateral membranaceous expansions containing a solid recurved spine.

Gaster subcircular, about as wide as long. First gastric tergite surrounded by a broad circular membranaceous border, interrupted only at the postpetiolar insertion.

Head and thorax somewhat shiny; the gaster and appendages subopaque, finely shagreened. Dorsum of head and thorax with squamiferous foveolae. Gaster without conspicuous foveolae. Scales short, rounded and canaliculate. No erect setae on first gastral tergite.

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL 4.52-4.88; HL 1.10-1.14; HW 1.62-1.68; EL 0.28; PW 1.24-1.32; PeW 0.88-0.97; PpW 0.84-0.93; HBaL 0.31; HBaW 0.19; CI 147.3-147.4; PI 127.3-130.6; PPeI 136.1-141.0; PPpI 141.0-147.6; HBaI 61.3.

Solider

Kempf (1952) - Length 5.0 mm. Median head length 1.27 mm. Weber's length of thorax 1.44 mm. Ferruginous-yellow. Funicular segments 2-9, tarsi, basal end of femora ferruginous. Anterior portion of pronotum, first gastral tergite, except a large circular ferruginous-yellow central area, pale orange to creamy. Marginal foliaceous crests glassy, semitransparent, dark orange around cephalic disc, paler on thorax and femora, almost colorless around gaster.

Head broader than long (80:63), surmounted by an elliptical, excavated disc, the borders of which are subperpendicularly upturned, having two vestigial denticules projecting from the mesal portion above occiput. Supramandibular excision about twice as broad as deep. Apical part of mandibles deflected downward, forming a distinct angle, visible from above as a crest running obliquely across the mandibles. Center of cephalic disc with a median convexity having a pair of antero-lateral extensions and a single postero-median branch. Postero-lateral portion of disc excavate and concave. Occipital lobes crested and obliquely truncate. Antennal scrobes ventral in position; part of cephalic disc above it semitransparent and membranaceous.

Thorax broader than long (69:56), with marginal membranaceous crests. Transverse pronotal carina strongly crested, interrupted mesally. Promesonotal suture obsolescent mesally. Sides of mesonotum with flattened, rounded and crested lobe. Mesoepinotal suture distinct. Epinotum broader than mesonotum, longitudinally convex with scarcely differentiated basal and declivous faces. A solid upturned tooth on each posterior corner of the basal face. Femora compressed, the apical half with a conspicuous dorsal and ventral crest. Tibiae short and stout, about twice as long as broad. Tarsi very short, the first and fifth segments less than twice as long as broad, segments 2-4 broader than long.

Petiole with a recurve and slender spine on each side, contained within the broad membranaceous border. Anterior and dorsal face of petiole continuously curved in profile. Postpetiole with a foliaceous spine on each side, projecting laterad and slightly cephalad.

Gaster subcircular, the median length subequal to the maximum width (67:69); excised antero-mesially, the remaining margin of the first tergite with a continuous membranaceous border.

Horizontal part of mandibles finely shagreened, deflected portions coarsely rugulose. Head except the excavated part of the disc, coarsely reticulate-rugose. Excavation smooth along the margins, finely reticulate-punctate in the center, with large, sparse, rounded, squamiferous foveolae. Dorsum of thorax and peduncular segments similarly sculptured, the foveolae being somewhat denser and the intervals almost smooth and shiny. Sides of thorax finely reticulate-striated. Appendages finely reticulate-punctate. Dorsum of gaster reticulate-punctate, the squamiferous foveolae very small, shallow, and vestigial.

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL 3.24 (without postpetiole and gaster missing in the sole known specimen); HL 1.28; HW 1.72; EL 0.28; PW 1.60; PeW 0.96; HBaL 0.32; HBaW 0.19; CI 134.4; PI 107.5; PPeI 166.7; HBaI 59.4.

Holotype Specimen Labels

Type Material

de Andrade and Baroni Urbani (1999) - Worker. Type locality: Pachitea River, Peru. Type material: one worker labelled "Peru, Pachitea, Stdg" Museo Civico di Storia Naturale, Genoa, 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 431, Combination in Cephalotes)
  • Emery, C. 1906c [1905]. Studi sulle formiche della fauna neotropica. XXVI. Bull. Soc. Entomol. Ital. 37: 107-194 (page 172, (footnote) fig. 32 worker described)
  • 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 8, soldier described, page 7, Combination in Paracryptocerus (Harnedia))