Formicoxenus gebaueri, Seifert, 2023

Seifert, Bernhard, 2023, Two new species of Formicoxenus Mayr 1855 and Leptothorax Mayr 1855 from Tibet (Hymenoptera: Formicidae), Soil Organisms 95 (2), pp. 129-142 : 137

Formicoxenus gebaueri n.sp.

Etymology: dedicated to the collector Axel Gebauer.

Type material:

Holotype and 7 paratype workers from the same nest labelled ‘ CHINA: 36.82°N, 102.53°E, Beishan Nat. Park , 2600 m, Picea-Pinus-Wald, Geröllhang. A. Gebauer 1996.05.30 ’

Diagnosis: --Worker ( Figs 14–17 , key). Numeric data given are arithmetic means based on measurement of 5 specimens (for standard deviation, minimum and maximum values see Tab. 1). Medium-sized, CS 738 µm.Head elongated, CL/CW 1.253. Genae in dorsal view nearly parallel. Median third of anterior margin of clypeus and hind margin of vertex in dorsal view straight. Frons narrower than in F. sibiricus (FRS/CS 0.432), scape slightly shorter (SL/CS 0.712. Eye very small, EYE/CS 0.164. Dorsal profile of promesonotum and propodeum slightly convex, metanotal depression moderately deep (MGr/CS 2.95 %). Spines rather short and acute (SP/CS 0.153), their bases moderately distant (SPBA/CS 0.289). Petiole with strong anterolateral corners, in profile without peduncle and with a less broad subpetiolar lobe. Postpetiolar sternite with a well-developed spine. All surfaces of head, mesosoma, waist and appendages matt due to a reticulate microsculpture. Dorsal vertex strongly longitudinally carinulate-rugulose. Gaster smooth and shiny but in contrast to F. sibiricus with subdecumbent to semierect setae. Head, mesosoma, waist, and gaster with long (PnHL/ CS 0.128) setae, tapering apicad ( Fig. 17 ) and round in cross-section. Color of head, mesosoma, waist and gaster homogenously yellowish brown.

Taxonomic comments. As a combination of long, tapering setae, well-developed sculpture on head, mesosoma, waist and appendages and narrower frons, Formicoxenus gebaueri n.sp. is unmistakable among the Palaearctic Formicoxenus species.

Biology. The type sample was collected below a stone within a Picea-Pinus forest on a slope with rubble. The host species was an undescribed species of the subgenus Serviformica Forel 1913 .

Figures

Figure 14–17: Formicoxenus gebaueri n.sp., holotype; (14) head in dorsal view; (15) lateral view (flipped horizontally); (16) dorsal view; (17) dorsolateral view on eye. China: Beishan National Park, 1995.05.30