Gnamptogenys sichuanensis

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Gnamptogenys sichuanensis
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Ectatomminae
Tribe: Ectatommini
Genus: Gnamptogenys
Species: G. sichuanensis
Binomial name
Gnamptogenys sichuanensis
Lattke, 2004

Nothing is known about the biology of Gnamptogenys sichuanensis.

Identification

Lattke (2004) - The following traits serve to separate Gnamptogenys from China that could be confused with G. sichuanensis. Gnamptogenys panda is distinguished by the anteromedian irregular strigae on the pronotum, the irregularly strigose mesopleuron, and the more weakly impressed mesopleural suture. The postpetiolar strigae lack anterior anastomization and the lateral rugulae of the fourth abdominal segment are lower, not as prominent. Gnamptogenys taivanensis can be separated from G. sichuanensis by its lack of an occipital lobe and the presence of short propodeal denticles. The postpetiolar dorsum of G. taivanensis is mostly longitudinally strigulose-punctate compared with the posterior thinning of the rugulae into very low transverse to arching strigulae in G. sichuanensis. The dorsum of the second gastric segment of G. taivanensis is mostly smooth with abundant punctae and occasional traces of longitudinal striae.

Keys including this Species

Distribution

Distribution based on Regional Taxon Lists

Palaearctic Region: China (type locality).

Distribution based on AntMaps

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Distribution based on AntWeb specimens

Check data from AntWeb

Biology

Not much is known about the the biology of Gnamptogenys sichuanensis. We can speculate that the biology of this species is similar to other species of the genus. Gnamptogenys are predatory ponerine ants that inhabit tropical and subtropical mesic forests. Nesting is typically at ground level in rotten wood or leaf litter. Some exceptions include species that are arboreal, a dry forest species and species that nests in sandy savannahs. Colony size tends to be, at most, in the hundreds. Queens are the reproductives in most species. Worker reproduction is known from a few species in Southeastern Asia. Generalist predation is the primary foraging/dietary strategy. Specialization on specific groups (millipedes, beetles, other ants) has developed in a few species.

Castes

Queen and male are unknown.

Nomenclature

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

  • sichuanensis. Gnamptogenys sichuanensis Lattke, 2004: 221, fig. 62 (w.) CHINA.

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

Occipital lobe well developed in lateral view, with thin, almost translucent lamella. Promesonotum longitudinally rugose-punctate; pronotal side and mesopleuron with parallel longitudinal strigae; postpetiolar dorsum anterad with anastomizing rugae.

Brown (1958:300, Fig. 18) misidentified the present two specimens of G. sichuanensis as G. panda.

Description

Worker

Lattke 2004 Gnamptogenys fig 61-63

Metrics. [Holotype] Paratype: HL [1.37] 1.35, HW [1.24] 1.23, ML [0.72] 0.71, SL [1.10] 1.13, ED [0.15] 0.16, WL [1.70] 1.78 mm. CI [0.91] 0.91, SI [0.89] 0.92, MI [0.58] 0.58, OI [0.12] 0.13. Head with posterior margin straight to weakly concave in dorsal view; anterior clypeal margin convex; clypeus anterolaterally with longitudinal strigulae, rugose-punctate posterad; frontal triangle U-shaped, with smooth bottom; longitudinal strigulae arch posterad over eyes becoming rugose-punctate laterally, frons laterally longitudinally strigulose, areolate toward vertex; posterior cephalic margin convex in lateral view; occipital lobes well developed, with thin, almost translucent lamella. Humeral angle well developed, not protuberant, without shallow posterior sulcus, laterally with longitudinal strigae separated by broad sulci, with anteroventral blunt angle and posteroventral rounded lobe; pronotal dorsum longitudinally rugose-punctate, rugae more continuous medially than laterally; promesonotal suture partially impressed, not breaking sculpture; mesopleuron longitudinally strigose, mesopleural suture well defined; mesosomal dorsum with dense longitudinal strigae, strigae irregular on propodeum; propodeum rugose-punctate, declivituous face with transverse carinae, rest smooth; mesosoma evenly convex until propodeal declivity in lateral view, declivity vertical, slightly convex.

Petiolar node rugose-punctate; subpetiolar process broadly triangular in lateral view, ventrally not cuneiform; postpetiolar dorsum with anterior anastomizing rugae, rugae diverging and less prominent posterad, posteromedially with arching strigulae, laterally with parallel strigae; sternite transversely strigose-punctate; postpetiolar process forms two contiguous convex lobes in ventral view, with median cleft and brief median carinae; fourth abdominal tergite with patches of longitudinal striae centered around punctae on smooth background, posterior margin strigulose-striate; sternite transversely strigose. Fore coxae laterally transversely strigose; fore tarsal dorsum punctate, with abundant pilosity; basal concavity with row of stout setae; metacoxal tooth low, triangular. Dorsum of thorax and abdominal segments 1-4 with scattered erect to subdecumbent hairs. Body with abundant golden decumbent pilosity; body brown; legs, antennae, and mandibles ferruginous brown.

Type Material

Holotype worker. China, Szechwan [Sichuan], near Muping, 6000ft [1829m], July 1929, D.C. Graham leg. Deposited in National Museum of Natural History. Paratype. Same data as holotype, but Sichuan is spelled "Szechuen," 1 worker in Museum of Comparative Zoology.

Etymology

The species name is derived from the name of the province that contains the type locality: Sichuan.

References

  • Lattke, J. E. 2004. A Taxonomic Revision and Phylogenetic Analysis of the Ant Genus Gnamptogenys Roger in Southeast Asia and Australasia (Hymenoptera: Formicidae: Ponerinae). University of California Publications in Entomology 122: 1-266 (page 221, fig. 62 worker described)