Tapinoma sichuense, Seifert & Kaufmann & Fraysse, 2024

Seifert, Bernhard, Kaufmann, Bernard & Fraysse, Lorenzo, 2024, A taxonomic revision of the Palaearctic species of the ant genus Tapinoma Mayr 1861 (Hymenoptera: Formicidae), Zootaxa 5435 (1), pp. 1-74 : 65-66

Tapinoma sichuense n.sp.

Etymology: referring to the Chinese province Sichuan where the two type samples were collected.

Type material: Holotype plus 2 paratype worker on the same pin labeled “ China, Sichuan, NW Jiuxiangzhen N 29.533, E 102.463, 1310 m asl., 2009-07-08, leg. Kabak, Chi 2009 242a”; 1 paratype worker labelled “CHI: 30.667°N, 100.758°E, Sichuan W. Qiaoqi 3 km S. 1950 m. 1997-07-11 ”, both samples deposited in SMN Görlitz.

Geographic range. Only known from the two type localities.

Diagnosis:—Worker ( Tab. 7 Figs. 17–19 ): All shape ratios given below are given in the sequence arithmetic mean [minimum, maximum]. Small-sized, CS 695 [665, 720]. Head less elongated than in dabashanica n. sp., CL/ CW 1.140 [1.126, 1.157]. Postocular rather small, PoOc/CL 0.397 [0.387, 0.404]. Anteromedian clypeal excision wider than deep, ExCly/CS 4.84 [4.69, 5.01]%, ExClyW 7.98 [7.51, 8.75]%. The margin of clypeal excision forms a sharp cuticular edge being at same level as the adjacent clypeal surface. Sum of pubescence hairs and smaller setae protruding at a few micron across margin of clypeal excision low, nExCly 2.0 [2.0, 2.0]. Posterior margin of head in full face view very feebly excavated, ExOcc/CS 0.50 [0.20, 0.77]%. Scape more elongated than in dabashanica n. sp., SL/CS 1.040 [1.004, 1.065]. Minimum distance of the inner margins of antennal socket rings medium-sized, dAN 0.305 [0.296, 0.309]. Eye rather large, EL/CS 0.284 [0.279, 0.289]. Dorsal profiles of mesonotum and of propodeum less convex than in dabashanica n. sp., metanotal depression rather shallow, MGr/CS 1.84 [1.29, 2.04]%. Mesosoma more slender than in dabashanica n. sp., MW/CS 0.662 [0.657, 0.665], ML/CS 1.377 [1.356, 1.394]. Second funiculus segment short, Fu2L/CS 12.74 [12.57, 12.97]%, IFu2 1.403 [1.313, 1.437]. Head, mesosoma and gaster covered by a rather dense pubescence. Anterior margin of clypeus with few short standing setae. Remaining surface of head capsule and dorsal mesosoma without standing setae, a few of these are present on mandibles, coxae and gaster sternites. Head, mesosoma, gaster, antennal scape, femora and tibiae dark to blackish brown. Tarsae, metatarsae and funiculus segments paler.

Taxonomic comments. It might be asked if the heterospecificity of Tapinoma dabashanica n. sp. and sichuense n. sp. appears credible considering the few specimens available. An first answer might be given when pooling the data of the 7 specimens of both species. This results in a coefficient of variation of 3.65% in the character ML/CS. The same coefficient is 2.28 ± 0.27 [1.78, 2.95]% in the 19 remaining Palaearctic species. Hence, considering conspecificity of Tapinoma dabashanica n. sp. and sichuense n. sp., the coefficient of variation in ML/CS would be clearly outside the intraspecific variance known in the genus. Another argument for heterospecificity is the differing mesosomal profile which is not caused by allometric effects because the absolute size of all specimens is very similar (compare Figs. 15 and 18 ). Furthermore, the mountainous type localities of T. dabashanica n. sp. and sichuense n. sp. are 700 km apart and separated by a wide lowland area.

Biology. Unknown.

Incertae Sedis

The following taxa have been allocated to the genus Tapinoma but a proper classification is impossible due to missing types and insufficient information in the original description.

Figures

FIGURE 15. Tapinoma dabashanica n. sp., holotype, lateral view, Gaoguan / China, 2010.05.18.

FIGURE 17. Tapinoma sichuense n. sp., holotype, head in full face view, Jiuxiangzhen /China, 2009.07.08.

FIGURE 18. Tapinoma sichuense n. sp., holotype, lateral view, Jiuxiangzhen /China, 2009.07.08.

FIGURE 19. Tapinoma sichuense n. sp., holotype, anterior head in dorsofronal view, Jiuxiangzhen /China, 2009.07.08.