Aenictus gutianshanensis

Aenictus gutianshanensis
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Dorylinae
Genus:	Aenictus
Species:	A. gutianshanensis
Binomial name
Aenictus gutianshanensis Staab, 2014 Specimen Labels

No direct biological information is available. The type series was collected in a single pitfall trap in a secondary mixed evergreen broad-leaved forest. Thus, the species probably lives and forages on and in the leaf-litter preying on small ants of the subfamily Formicinae, as it has been previously reported for species in the A. wroughtonii group (Rościszewski and Maschwitz 1994, Jaitrong et al. 2010). Possible prey species of the genera Prenolepis and Nylanderia are common at the type locality (Staab, 2014).

Identification

dorsal view of pronotum

Stabb (2014) - Aenictus gutianshanensis can be easily distinguished from all other species of the wroughtonii group by the pronotum, the petiole, and the side of the postpetiole completely finely reticulate. The new species is most similar to Aenictus vieti and Aenictus camposi but slightly larger in all measurements. In addition to having the pronotum and petiole completely finely reticulate, A. gutianshanensis can be easily distinguished from A. vieti and A. camposi by the following characters (characters for A. vieti and A. camposi are given in brackets): ventral margin of subpetiolar process almost straight (ventral margin convex), femora densely punctate (smooth and shiny in Jaitrong et al. 2010, but superficially and irregularly sculptured and shiny in two paratypes examined by the reviewer), postpetiolar process more developed with a rim below (less developed, without ventral rim), and longest standing hairs on pronotal dorsum distinctly longer (maximal 0.13 mm).

Keys including this Species

• Key to Aenictus wroughtonii group species

Distribution

South-East China

Latitudinal Distribution Pattern

Latitudinal Range: 29.215° to 29.215°.

North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

• Source: AntMaps

Distribution based on Regional Taxon Lists

Palaearctic Region: China (type locality).

Distribution based on AntMaps

Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.

Habitat

Biology

Explore Overview of Aenictus biology  Little is known about the biology of Aenictus gutianshanensis. The genus is comprised of species that live an army ant lifestyle. Aenictus typically prey on other ants, from other genera, or other insects such as wasps or termites. There are reports of Aenictus preying on other insects as well and even have been observed collecting honeydew from homopterans (Santschi, 1933; Gotwald, 1995) but this appears, at least from available evidence, to be uncommon. Foraging raids can occur day or night across the ground surface. Occasionally raids are arboreal. During a raid numerous workers attack a single nest or small area, with several workers coordinating their efforts to carry large prey items back to the nest or bivouac. Aenictus have a nomadic life style, alternating between a migratory phase in which nests are temporary bivouacs in sheltered places above the ground and a stationary phase where semi-permanent underground nests are formed. During the nomadic phase bivouacs move regularly, sometimes more than once a day when larvae require large amounts of food. Individual nests usually contain up to several thousand workers, although nest fragments containing only a few hundred workers are often encountered. Queens are highly specialised and look less like workers than in most ant species. They have greatly enlarged gasters (dichthadiform) and remain flightless throughout their life. New colonies are formed by the division of existing colonies (fission) rather than by individual queens starting colonies on their own. ‎

Castes

Known only from the worker caste.

Nomenclature

The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

• gutianshanensis. Aenictus gutianshanensis Staab, 2014: 67, figs. 1-5 (w.) CHINA (Zhejiang).
  • Type-material: holotype worker, 5 paratype workers.
  • Type-locality: holotype China: Zhejiang Prov., Gutianshan National Nature Reserve, ca 30 km. NW Kaihua, 29°12’54’’N, 118°7’18’’E, ca 250 m., 28.vi.2009, CSP26/SW7(2009), pitfall trap (A. Schulz); paratypes with same data.
  • Type-depositories: IZAS (holotype); CASC, IZAS, MNHU (paratypes).
  • Status as species: Jaitrong & Ruangsittichai, 2018: 113 (in key).
  • Distribution: China.

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

Description

Worker

Measurements and indices. Holotype: TL 3.30, HL 0.68, HW 0.63, SL 0.70, ML 1.17, MTL 0.75, PL 0.30, CI 93, SI 112. Paratypes (n=5): TL 3.10–3.30, HL 0.69–0.75, HW 0.60–0.65, SL 0.65–0.70, ML 1.17–1.25, MTL 0.69–0.83, PL 0.29–0.31, CI 87–91, SI 104–113.

Head in full-face view elliptical, slightly longer than broad, with convex sides and almost straight posterior margin of head. Antennal scape long, reaching posterior corner of head; antennal segments II-X each longer than broad; II as long as III, but longer than each of IV-VII; terminal segment (X) longer than each of II-IX; the last four segments forming an indistinct club. Frontal carina long, extending slightly beyond the posterior margin of antennal torulus. Clypeus short with its anterior margin slightly convex, bearing 7-8 bluntly rounded denticles. Mandible subtriangular, masticatory margin straight, with a large curved apical tooth which is followed by 9-10 minutes teeth on masticatory margin. With mesosoma in profile, pronotum dorsally convex, not distinctly separated from mesonotum by a promesonotal suture. Propodeum slightly lower than promesonotum, its dorsal outline gently sloping posteriorly; propodeal junction angulate; declivity of propodeum straight in the dorsal part, concave in the ventral part when viewed in profile, encircled by a thin rim. Petiole in profile as long as high, its node convex dorsally. Subpetiolar process present, its ventral margin almost straight, bearing a thin rim below, anteroventral corner angulate. Postpetiole slightly longer than petiole, its node convex dorsally in profile; ventral postpetiolar process developed, angulate, bearing a thin rim below, slightly projecting over the posterior part of the petiole.

Head including mandible smooth and shiny; antennal scape punctate. Entire mesosoma finely reticulate, dorsal face of pronotum finely reticulate but shiny, reticulation on mesopleuron, metapleuron and lateral face of propodeum finer than on pronotum, appearing almost punctate in magnification lower 64×. Entire petiole finely reticulate. Postpetiole finely reticulate, except the dorsum smooth and shiny. Gaster smooth and shiny. Coxae finely reticulate, femora densely punctate, tibiae sparsely punctate.

Body except anterior part of mesonotum with abundant standing hairs and interdispersed short hairs; length of longest hairs on dorsa of head and pronotum 0.20–0.30 mm. Antennal scape and legs with abundant standing hairs. Head, mandible, gaster and legs yellowish brown. Mesosoma, antennal scape, petiole and postpetiole reddish brown.

Type Material

Holotype. Worker from China, Zhejiang Province, Gutianshan National Nature Reserve, ca. 30 km NW of Kaihua, 29°12'54"N / 118°7'18"E, ca. 250 m above sea level, 28.VI.2009, leg. Andreas Schuldt, label: “CSP26/SW7(2009)”, deposited in Institute of Zoology, Academia Sinica (Chinese Academy of Sciences). Paratypes. Five workers, same data as holotype. Three deposited in IZAS; one each deposited in ZMBH and California Academy of Sciences. All type specimens were collected in a single pitfall trap in a secondary mixed evergreen broad-leaved forest.

Etymology

The scientific name is after the type locality, the Gutianshan National Nature Reserve in South-East China.

References

• Staab, M. 2014. A new species of the Aenictus wroughtonii group (Hymenoptera, Formicidae) from South-East China. ZooKeys 391, 65–73 (doi: 10.3897/zookeys.391.7213).

References based on Global Ant Biodiversity Informatics

• Staab M. 2014. A new species of the Aenictus wroughtonii group (Hymenoptera, Formicidae) from South-East China. ZooKeys 391: 65–73. doi: 10.3897/zookeys.391.7213
• Staab M., A. Schuldt, T. Assmann, H. Bruelheide, and A.M. Klein. 2014. Ant community structure during forest succession in a subtropical forest in South-East China. Acta Oecologia 61: 32-40.