Sceloattalus nigroprominens Tong & Yang, 2023

Tong, Junbo, Tshernyshev, Sergei E., Liu, Haoyu & Yang, Yuxia, 2023, First record of the genus Sceloattalus Wittmer, 1966 (Coleoptera, Malachiidae) from China, with description of a new species, ZooKeys 1181, pp. 1-7 : 1

Sceloattalus nigroprominens Tong & Yang sp. nov.

Figs 1 , 2

Diagnosis.

This species is similar to Sceloattalus kopetzi Tshernyshev, 2015 but can be distinguished from the latter by the antennae mostly yellow with a small black spot at apex of last antennomere, elytra without metallic lustre, and tarsi of all legs yellow. In contrast, S. kopetzi has antennae mostly black with antennomeres 1-4 yellow, elytra with blue-metallic lustre, and tarsi yellow to black.

Materials examined.

Holotype: China: Xizang: ♂, Nang, Nyingchi , 3100 m elev., 29.VI.1997, Chaodong Zhu leg (IZAS) . Paratype: China: Xizang: 1♀, same data as holotype (IZAS). The type specimens are deposited in Institute of Zoology, Chinese Academy of Sciences , Beijing, China (IZAS) .

Description.

Male. Length of body 4.8 mm; width at widest part of elytra 1.9 mm and at the base of elytra 1.5 mm.

Body yellow, with elytra and metathorax black. (Fig. 1A ). Mandibles somewhat black. Antennae with a small black spot at apex of last antennomere. Fore legs with a small black spur-like comb on tarsomere 2 (Fig. 2A ), hind legs yellow to black. Vesicles and thoracic mesepimera yellow. Elytra covered with black setae, while head and pronotum double consisting of yellow adpressed pubescence and sparse black stiff bristles. Sculptures evenly punctuated, stronger on elytra than other parts.

Head narrower than pronotum. Frons slightly impressed. Clypeus distinct. Antennae filiform extending over the apical quarter of the elytra; antennomere 1 elongate and clavate; 2 shortened and rectangular; 3 and 4 slightly widened; 5-11 cylindrical and approximately equal in length.

Pronotum transverse, anterior margin slightly protruding, posterior margin flattened and curved upwards.

Scutellar shield small, triangular, almost completely covered by pronotum.

Elytra slightly widened behind base; base of elytra approximately as wide as pronotum. Humeri distinct, slightly protruding. Disc without metallic lustre. Elytral apices evenly rounded.

Hind wings normally developed.

Legs slender. Hind femora not reaching elytral apices. All tibiae thin and straight. All tarsi with 5 tarsomeres; tarsomere 2 of fore tarsi produced in a spur-like comb, not extending over the tarsomere 3 (Fig. 2A ); tarsomere 1 longest and tarsomere 4 shortest in mid and hind legs. Claws thin, curved, with membrane at base and long setae at middle.

Metathorax simple, lacking appendages. Pygidium (apical tergite) broad, with triangular emargination on distal side (Fig. 2B ); ultimate abdominal ventrite (apical sternite) short, transverse, with a triangular emargination terminally (Fig. 2C ). Tegmen short and wide; aedeagus stout, slightly narrowing to blunt apex in ventral view (Fig. 2D, E ).

Female. Length of body 4.8 mm; width at widest part of elytra 1.9 mm and at the base of elytra 1.5 mm.

Similar to male species except for hind legs uniformly yellow and not dilated at apices of tibiae (Fig. 1B ). Pygidium subtrapezoid (Fig. 2G ). Ultimate abdominal ventrite subtriangular, with long spiculum ventrale (Fig. 2H ). Ovipositor elongate and membranous (Fig. 2I ).

Distribution.

China (Xizang).

Etymology.

The specific epithet Sceloattalus nigroprominens derives from the Latin words " niger " (black) and " prominens " (prominent) and refers to the black prominence on hind tibiae.

Figures

Figure 1. Habitus of Sceloattalus nigroprominens Tong & Yang, sp. nov., dorsal views A holotype, male B paratype, female. Scale bars: 1.0 mm.

Figure 2. Sceloattalus nigroprominens Tong & Yang, sp. nov. A-F, holotype, male A fore tarsi B pygidium (apical tergite) C ultimate abdominal ventrite (apical sternite) D male genitalia, lateral view E male genitalia, ventral view F hind tibia G-I paratype, female G pygidium (apical tergite) H ultimate abdominal ventrite (apical sternite) I ovipositor. Scale bars: 0.2 mm.