Proceratium brasiliense

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Proceratium brasiliense
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Proceratiinae
Tribe: Proceratiini
Genus: Proceratium
Species: P. brasiliense
Binomial name
Proceratium brasiliense
Borgmeier, 1959

Proceratium brasiliense ufv-labecol-000053 p 1 high.jpg

Proceratium brasiliense ufv-labecol-000053 d 1 high.jpg

Specimen Labels

Nothing is known about the biology of Proceratium brasiliense.

Identification

A member of the micrommatum clade. The sister species of Proceratium catio (q. v.), but differs from it, in the worker and gyne, by the petiole 1/8 longer than broad instead of 1/5 longer than broad, by the postpetiole longer than 1/2 of the gastral tergite I (LT4) instead of slightly shorter, and by the postpetiole and gaster less convex than in catio. (Baroni Urbani and de Andrade 2003)

Keys including this Species

Distribution

Distribution based on Regional Taxon Lists

Neotropical Region: Brazil (type locality).


Distribution based on AntMaps

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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

Nomenclature

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

  • brasiliense. Proceratium brasiliense Borgmeier, 1959a: 309, figs. 1, 2 (w.) BRAZIL. Baroni Urbani & De Andrade, 2003b: 143 (q.).

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

Description

Worker

Baroni Urbani and de Andrade (2003) - Head slightly longer than broad and with subparallel sides. Vertex convex in full face view. Clypeus corresponding to a small triangular tooth between the antennal sockets. Frontal carinae close to each other, not covering the antennal insertions. Frontal area behind the frontal carinae weakly convex. Lateral expansions of the frontal carinae relatively narrow, raised, diverging or subparallel. Genal carinae present and well marked. A superficial sulcus between the genal carinae and the gular area. Eyes present, composed by a clearly convex facet slightly below the midline of the head. Scapes thicker in the distal half and short of the vertexal margin. First funicular joint 1/3 longer than broad. Funicular joints 2-10 broader than long. Last funicular joint as long as the sum of joints 7-10. Mandibles with 3-4 denticles before the apical tooth. Palp formula 3,2.

Mesosoma slightly elongate. Promesonotal suture superficially impressed. Promesopleural and mesometapleural sutures impressed on the ventral half only. Basal face of the propodeum with a relatively high tumulus medially; area behind the propodeal tumulus with a superficial transversal sulcus; postero-lateral border of the sulcus with or without a minute, carinate angle. Declivous face of the propodeum flat; its sides submarginate. Propodeal lobes ventrally truncate and dorsally round. Propodeal spiracles small.

Petiole slightly longer than broad, with sides subparallel in the anterior fourth and convex posteriorly in dorsal view. Anterior border of the petiole with a superficially carinate tooth on each side, the teeth separated by a concavity. Ventral process of the petiole with one or two minute denticles followed or not by a small spine. Postpetiole longer than 1/2 of the gastral tergite I (LT4), with the sides gently convex in dorsal view. Postpetiolar sternite anteromedially with a marked subtriangular projection. Posterior half of the postpetiolar sternite slightly convex. Constriction between postpetiole and gastral segment I impressed. Gastral tergite I broad and round. Gastral sternite I very short medially. Remaining gastral tergites and sternites curved ventrally.

Legs slightly elongate. Mid tibiae without spur. Spurs of fore legs without basal spine. Fore basitarsi longer than the mid ones. Hind basitarsi about 1/5 shorter than hind tibiae. Second tarsomere of mid and hind legs longer than third and fourth tarsomeres, and shorter than pretarsus. Pretarsal claws simple. Arolia small.

Sculpture. Head, mesosoma, petiole and postpetiole granulate, and with traces of very superficial, small, irregular, foveae-like depressions. Few, irregular, short rugosities may be present between these structures. Dorsum of the first gastral tergite smooth and with minute piligerous punctures and very sparse minute granulation; area after the gastral curvature and sides of the gaster granulate. Scapes and legs less granulate than the other body parts.

Body covered by hairs of three main types: (1) short, dense, subdecumbent on the whole body, sparse and erect on the funicular joints; (2) long, erect or suberect and sparse on the whole body, absent from the tumulus of the basal face of the propodeum and on the antennae, slightly longer on the petiole; (3) shorter than hair type (1), dense, subdecumbent and appressed on the funicular joints only. In addition the funicular joints bear whitish, thick, appressed, short, sparse hairs, and the scapes with sparse hairs similar to type (2) but shorter.

Colour light or dark ferrugineous. Antennae and legs lighter.

Measurements in mm and Indices: TL 3.40-3.86; HL 0.77-0.90; HW 0.70-0.80; EL 0.05-0.06; SL 0.52-0.58; WL 0.94-1.03; PeL 0.35-0.36; PeW 0.31-0.34; HFeL 0.62-0.70; HTiL 0.51-0.59; HBaL 0.41-0.48; LS4 0.15-0.18; LT4 0.77-0.94; CI 88.9-91.7; SI 64.4-67.5; IGR 0.19-0.22.

Queen

Baroni Urbani and de Andrade (2003) - (previously undescribed). It differs from the worker in the following details: eyes large, about 1/4 of the head length and with ocular pilosity. Ocelli well developed. Funicular joints 2-10 slightly broader than long. Mandibles with 4-5 denticles before the apical tooth.

Mesosoma robust and convex in side view. Parapsidal furrows marked. Scutellum convex. Metanotum without tooth or spine-like projection. Basal face of the propodeurn very short, with or without a denticle on each side, mcdially incised and almost indistinguished from the declivous face.

Petiole in dorsal view subparallel in the anterior third or fourth and convex posteriorly. Anterior and dorsal faces of the petiolar node less convex. Postpetiole in dorsal view with convex sides.

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

Sculpture as in the worker.

Pilosity as in the worker except for the hair type (2) present on the whole propodeum. Colour light ferrugineous.

Measurements in mm and Indices: TL 3.65-4.21; HL 0.79-0.89; HW 0.70-0.82; EL 0.20-0.21; SL 0.57-0.72; WL 1.08-1.20; PeL 0.32-0.36; PeW 0.30-0.34; HFeL 0.69-0.83; HTiL 0.55-0.66; HBaL 0.45-0.56; LS4 0.16-0.22; LT4 0.85-1.05; CI 89.9-92.2; SI 72.1-80.9; IGR 0.19-0.21.

Type Material

Baroni Urbani and de Andrade (2003) - Type locality: Nova Teutenia, Xaxim, Cantareira, Brazil. Type material: two syntype workers labelled: "Brasilien Nova Teutonia, 27°11' B 52°23' L, 300 bis 500 mm, VIII.1957, X.1957, Fritz Plaumann; Cotypus; Syntypus; Proceratium brasiliense Cotype, det. Borgmeier"; one syntype worker labelled: "Xaxim, SC, XII.1957, F. Plaumann, Cotypus, Syntypus"; one worker labelled: Cantareira, SP, 1.11.59, Kempf & Santos, Cotypus, Syntypus", all in Museu de Zoologia da Universidade de Sao Paulo, examined.

References