Adota kamchatkaensis Yoo and Ahn, 2024

Yoo, In-Seong, Jung, Jong-Keun & Ahn, Kee-Jeong, 2024, Description of a new coastal Adota Casey (Coleoptera: Staphylinidae: Aleocharinae) species from Kamchatka, Zootaxa 5433 (4), pp. 595-600 : 595-596

Adota kamchatkaensis Yoo and Ahn , sp. nov.

( Figs. 1–4 )

Description. Length 3.2–4.2 mm. Body dark brown to black; head and pronotum almost black; antenna and legs paler than other parts; surface fairly glossy, imbricate and densely pubescent. Head. Slightly transverse, approximately 1.1 times as wide as long, widest across eyes, about as wide as pronotum; eye slightly prominent, about 0.8 times as long as temple; gular sutures widely separated; occipital carina and cervical carina present. Antenna ( Figs. 2A , 3A ) long and slender; antennomeres 1–3 elongate, 1 longest, 4 almost as long as wide, 5–10 variable, quadrate to subquadrate, occasionally 5–7 slightly elongate, 11 as long as the preceding two combined. Mouthparts. Labrum strongly transverse, anterior margin truncate, α- β- γ- ε-sensillum and about 8 long macrosetae present on each side of midline. Mandibles asymmetrical, subtriangular, decurved and pointed apically, about 1.4–1.5 times as long as basal width; right one with small internal tooth, internal margin slightly serrulate; prostheca developed. Galea and lacinia of maxilla long and slender; lacinia composed of six spines in distal comb region, two isolated spines present; maxillary palpus elongate with pubescence and long setae; palpomere 1 smallest, 2 about 2.8–3.0 times as long as wide, 3 slightly longer than 2, about 2.8 times as long as wide, 4 digitiform, filamentous sensilla reaching to basal half. Labium with ligula very long and slender, divided into two lobes in basal half; prementum with two medial setae narrowly separated; medial pseudopores, several lateral pseudopores, one setal pore and several pores present on each side of midline; labial palpus elongate, with many setulae; palpomere 1 largest, about 1.8–2.0 times as long as wide, 2 shortest, about 1.2–1.3 times as long as wide, 3 more or less dilated apically and about as long as 1, about 2.4 times as long as wide. Mentum trapezoidal, anterior margin emarginate. Thorax. Pronotum roundly subquadrate, approximately 1.3 times as wide as long, widest in apical third; hypomeron fully visible in lateral aspect. Metanotal scutum with one long seta and about 3–5 short setae on each side of midline. Mesoventral process distinctly pointed at apex; length ratio of mesoventral process, isthmus and metaventral process 40:15:11; metendosternite Y-shaped, basal stalk longer than furcal arm. Elytra parallel-sided, slightly wider than pronotum; elytron approximately 1.6–1.8 times as long as wide, pubescence directed postero-laterally; postero-lateral margin straight; hind wing fully developed, flabellum composed of about 8–10 long setose lobes. Leg slender and long, with dense pubescence and macrosetae; middle and hind tibia with different length of two spurs at apex; empodial seta almost as long as claw; length ratio of tarsomeres 18:20:22:49 (front tarsus); 25:26:26:25:47 (middle tarsus); 33:31:33:34:63 (hind tarsus). Abdomen. Parallel-sided, convergent at apex; surface strongly glossy, with imbricate microsculpture; male tergite VIII ( Figs. 2B , 3B ) with five macrosetae on each side of midline, posterior margin emarginate medially; male sternite VIII ( Figs. 2D , 3D ) with nine macrosetae on each side of midline, posterior margin rounded; female tergite VIII ( Figs. 2C , 3C ) with five macrosetae on each side of midline, posterior margin similar to male but less emarginate medially; female sternite VIII ( Figs. 2E , 3E ) with five macrosetae on each side of midline, posterior margin broadly rounded, with long marginal setae, minute setae present in median region. Aedeagus. Median lobe ( Fig. 3F–G ) ovate, apical process broad and slowly convergent to apex in ventral aspect; internal sac complicated.Apical lobe of paramerites ( Fig. 3H ) with four setae; a- and b-setae long, a- slightly longer, c- and d-setae short and subequal in length. Spermatheca. Bursa elongate, with conical-shaped umbilicus; duct relatively slender, slowly narrowed to apex until coiled, coiled at apex ( Fig. 3I ).

Specimens examined. Holotype: 1♂ ( CNUIC), with labels as follows: “ Russia: Kamchatka, Petropavlovskkamchatsky, inlet of Avacha Bay , N52°55′55.4″ E158°41′17.6″, 28 VII 2011, KJ Ahn, IS Yoo, under seaweeds on seashore | Holotype Adota kamchatkaensis Yoo and Ahn, 2023 ” . Paratypes: 46 exx. (23 in 95% ETOH and 7 on slide), same data as holotype; 11 exx. (9 in 95% ETOH and 2 on slide), Russia: Kamchatka, Petropavlovskkamchatsky, inlet of Avacha Bay , N52°54′47.6″ E158°41′14.2″, 28 VII 2011, KJ Ahn, IS Yoo, under seaweeds on seashore .

Distribution. Russia (Kamchatka).

Etymology. Named after the locality of collected specimens.

Remarks. This species is similar to A. ushio , but can be distinguished by emarginate posterior margin of male abdominal tergite VIII, rounded posterior margin of male abdominal sternite VIII, and the different form and internal structure of the aedeagus and spermatheca ( Table 1 ). This also resembles A. madida (Bernhauer) in male tergite VIII and the shape of spermatheca. However, the new species does not possess the bifurcate microsetae on the posterior margin of male sternite VIII (fig. 8G in Sawada 1977) and the form of the aedeagus is different from that of A. madida (fig. 8H in Sawada 1977).

Figures

FIGURE 1. Habitus. A Adota kamchatkaensis Yoo and Ahn, sp. nov., 3.4 mm; B Adota ushio, 3.0 mm.

FIGURE 2. Line drawings of Adota kamchatkaensis Yoo and Ahn, sp. nov. A Antenna; B Male tergite VIII, dorsal aspect; C Female tergite VIII, dorsal aspect; D Male sternite VIII, ventral aspect; E Female sternite VIII, ventral aspect. Scale bars = 0.1 mm.

FIGURE 3. Microphotographs of Adota kamchatkaensis Yoo and Ahn, sp. nov. A Antenna; B Male tergite VIII, dorsal aspect; C Female tergite VIII, dorsal aspect; D Male sternite VIII, ventral aspect; E Female sternite VIII, ventral aspect; F Median lobe, lateral aspect; G Median lobe, ventral aspect; H Paramere, lateral aspect; I Spermatheca. Scale bars = 0.1 mm.

FIGURE 4. Habitat of Adota kamchatkaensis Yoo and Ahn, sp. nov. A Seaweed on a beach, Kamchatka, Russia; B Close up of seaweed.