Proceratium longiscapus

AntWiki - Where Ant Biologists Share Their Knowledge
Jump to: navigation, search
Proceratium longiscapus
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Proceratiinae
Tribe: Proceratiini
Genus: Proceratium
Species: P. longiscapus
Binomial name
Proceratium longiscapus
De Andrade, 2003

MCZ-ENT0035686 Proceratium longiscapus hal.jpg

MCZ-ENT0035686 Proceratium longiscapus had.jpg

Specimen Label

Known from a single queen collected at a light trap.

Identification

A member of the micrommatum clade. Differing from all the other species of the clade, in the gyne, by the antennal scapes reaching the cephalic vertex posteriorly and by the antennal joints longer than broad (Baroni Urbani and de Andrade 2003)

Distribution

Distribution based on Regional Taxon Lists

Neotropical Region: Dominican Republic (type locality), Greater Antilles.

Distribution based on AntMaps

AntMapLegend.png

Distribution based on AntWeb specimens

Check data from AntWeb

Biology

Very little is known about the biology of Proceratium ants. They nest in soil, rotten wood, under deep-set stones and, in a few cases, tree branches. For many species the nest consists of small rounded chambers hollowed out of soft rotten wood or in the soil. Toward the cooler limits of the range, particularly in North America, nests and foraging workers are found under deep set rocks instead of in rotten wood. The nest site is usually in forest shade, in old moist gardens, or similar habitats that are constantly moist. Some species of known to be egg predators of arthropods, especially of spiders.

Most Proceratium are relatively rare but this is not the full explanation for why they are not commonly collected. Colonies of most species are small. Based on anectdotal natural history information from a few species, it was once thought that most Proceratium would likely be found to have mature colonies that contain somewhere between 10 - 50 workers. Yet nests with more than 50, and in some cases up to 200, workers have been been reported. Besides small colonies, these ants also do not appear to forage in places where they are readily encountered.

Males and females are though to be produced in small numbers but we generally do not have enough data for colonies of any species to know what might be typical. Reproductive flights have been observered toward the end of the summer in some northern temperate areas. In these regions the nuptial flight occurs during the last half of August. Both sexes climb some distance from the nest entrance before taking flight. Workers too issue from the nest during the nuptial flight, as is often the case with otherwise cryptobiotic ants.

Castes

Workers and males are unknown.

Nomenclature

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

  • longiscapus. Proceratium longiscapus De Andrade, in Baroni Urbani & De Andrade, 2003b: 190, figs. 81, 82 (q.) DOMINICAN REPUBLIC.

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

Description

Queen

Head longer than broad and with subparallel sides. Vertex in full face view weakly convex. Clypeus reduced, subround and slightly longer than the antennal sockets. Antenna1 socket with broad torulus. Frontal carinae close each other, not covering the antennal insertions. Frontal area behind the frontal carinae weakly convex. Lateral expansions of the frontal carinae relatively narrow, feebly raised and parallel. Genal carinae marked. A sulcus between the genal carinae and the gular area. Eyes large, about 1/4 of the head length and with ocular pilosity. Ocelli well developed. Scapes reaching the vertexal margin. First funicular joint about 1/2 longer than broad. Funicular joints 2-10 longer than broad. Last funicular joint about as long as the sum of joints 6-10. Mandibles with 4 denticles before the apical tooth. Palp formula probably 3,2.

Mesosoma convex in side view. Parapsidal furrows marked. Scutellum with the sides converging posteriorly and with the posterior border rounded. Metanotum without triangular tooth. Basal face of the propodeum short, weakly angulate laterally, incised and almost as flat as the declivous face medially. Propodeal lobes round. Propodeal spiracles small.

Petiole longer than broad, with the sides subparallel in the anterior third and convex posteriorly in dorsal view. Anterior border of the petiole almost straight and carinate. Ventral process of the petiole corresponding to a narrow, crenulate, longitudinal lamella. Postpetiole slightly shorter than 1/2 of the gastral tergite I (LT4), with the sides gently convex in dorsal view. Postpetiolar sternite anteromedially with a subtriangular projection. Posterior half of the postpetiolar sternite flat. Constriction between postpetiole and gastral segment I impressed. Gastral tergite I convex on the curvature. Gastral sternite I short medially. Sides of gastral sternite I flat and not protruding anteriorly. Remaining gastral tergites and sternites curved ventrally.

Mid tibiae without spur. Spurs of fore legs without basal spine. Fore basitarsi longer than the mid ones. Hind basitarsi about 116 shorter than hind tibiae. Second tarsomere of mid and hind legs longer than the third and fourth and slightly shorter than pretarsus. Pretarsal claws simple. Arolia very small.

Fore wings of our type 4, hind wings of our type 3 as defined in the description of the genus.

Sculpture. Head with small reticulation, sparsely rugulose and granulate. Pronotum, scutellum, pleurae and basal face of the propodeum with small granulation and rare, short, thin, rugosities, the rugosities ticker on the metapleurae. Mesonotum with superficial, srnall piligerous punctures. Petiole and postpetiole granulate. First gastral tergite superficially smooth and covered by small piligerous punctures, larger on the sides. Legs punctate.

Body covered by hairs of three main types: (1) short, dense, subdecumbent on the whole body; (2) longer than hair type (I), erect and sparse on the whole body, shorter on the scapes; (3) shorter than hair type (I), dense, decumbent on the funicular joints only. In addition the funicular joints bear whitish, sparse, tick, appressed hairs and suberect hairs similar to type (1) but slightly shorter.

Colour light brown.

Measurements in mm and Indices: TL 3.15; HL 0.71; HW 0.58; EL 0.18; SL 0.60; WL 0.90; PeL 0.31; Pew 0.26; HTiL 0.48; HBaL 0.40; LS4 0.19; LT4 0.80; CI 81.6; SI 84.5; IGR 0.24.

Type Material

Holotype gyne from the Dominican Republic labelled "Dominican Republic, Bonao, 29.VIII.1997, C. O'Brien & R. Baronowski, blacklight trap", In Museum of Comparative Zoology. MCZ-ENT0035686

Etymology

From the Latin longus (= long) and scapus (= stalk), referred to the most salient morphological trait of this species.

References

  • Baroni Urbani, C., de Andrade, M.L. 2003. The ant genus Proceratium in the extant and fossil record (Hymenoptera: Formicidae). Museo Regionale di Scienze Naturali, Monografie, 36, 1–492. (page 190, figs. 81, 82 queen described)