Hydrosmecta koreana Lee & Ahn, 2024

Lee, Seung-Gyu & Ahn, Kee-Jeong, 2024, Korean species of Hydrosmecta Thomson (Coleoptera: Staphylinidae: Aleocharinae) with descriptions of two new species, Zootaxa 5399 (3), pp. 265-274 : 269

publication ID	https://doi.org/ 10.11646/zootaxa.5399.3.5
publication LSID	lsid:zoobank.org:pub:5BEEF684-5E7D-4C2D-B71B-70A994C8FD79
DOI	https://doi.org/10.5281/zenodo.10516870
persistent identifier	https://treatment.plazi.org/id/A7078785-3977-FF87-FF31-EF80FEE903AB
treatment provided by	Plazi
scientific name	Hydrosmecta koreana Lee & Ahn
status	sp. nov.

Treatment

Hydrosmecta koreana Lee & Ahn , sp. nov.

( Figs. 1B View FIGURE 1 , 3A–F View FIGURE 3 , 4A–H View FIGURE 4 , 5A–B View FIGURE 5 , 6A–H View FIGURE 6 )

Description. Length about 2.0– 2.3 mm. Body surface fairly glossy and densely pubescent, with fine microsculpture. Body dark brown; antennae, elytra and legs slightly paler. Head. Quadrate ( Fig. 4A View FIGURE 4 ), about as wide as long, widest across eyes, about as wide as pronotum; eye large and distinctly prominent, about 1.4–1.5 times as long as temple; gular sutures moderately separated, more or less diverged basally; infraorbital carina absent; cervical carina absent. Antennomeres ( Fig. 4B View FIGURE 4 ) distinctly elongate, 1 longest, 2 slightly longer than 3, 4 shortest, 11 about as long as 1, slightly shorter than preceding two combined. Mouthparts. Labrum ( Fig. 3A View FIGURE 3 ) distinctly transverse, emarginate in anterior margin, with ε-sensillum and 6 macrosetae on each side of midline; epipharynx with several sensilla, including 2 lateral sensory rows on each side of midline; α-sensillum setaceous, less than 2.0 times as long as ε-sensillum; β- and γ-sensilla very short, pointed at apex. Mandibles ( Fig. 3C–D View FIGURE 3 ) asymmetrical, elongate, decurved and pointed apically, approximately 1.8 times as long as basal width, internal margin slightly serrulate; right one ( Fig. 3C View FIGURE 3 ) with pointed internal tooth; prostheca developed, composited three portions. Galea and lacinia of maxilla ( Fig. 3E View FIGURE 3 ) slightly long and slender; lacinia composited seven spines in distal comb region, two isolated spines present; last spine of distal comb region and isolated spines close together; maxillary palpus elongate and pubescent; palpomere 1 smallest, 2 about 2.6–2.8 times as long as wide, 3 slightly longer than 2, about 2.2–2.4 times as long as wide, 4 digitiform, filamentous sensilla reaching to basal half. Labium ( Fig. 3F View FIGURE 3 ) with ligula elongate and parallel-sided, divided into 2 lobes in apical half; prementum with 2 medial setae moderately separated; 2 basal pores narrowly separated, about 1.0–2.0 times width of basal pore; a few median pseudopores present, several lateral pseudopores, 1 setal pore and 2 real pores present on each side of midline; labial palpus elongate, with many setulae; palpomere 1 largest, about 1.7–1.8 times as long as wide, with γ-setula close to b-seta, 2 shortest, about 1.2–1.3 times as long as wide, 3 parallel-sided and slightly shorter than 1, about 3.5–4.0 times as long as wide. Mentum ( Fig. 3F View FIGURE 3 ) trapezoidal, anterior margin slightly emarginate; v-seta very short. Thorax. Pronotum ( Fig. 4C View FIGURE 4 ) transverse, 1.2 times as wide as long, widest in apical third, pubescence directed anteriorly in median region; hypomeron fully visible in lateral view. Scutellum as in Fig. 4G View FIGURE 4 . Metanotal scutum ( Fig. 4E View FIGURE 4 ) with 1 long seta and about 4–6 short setae on each side of midline. Mesoventral process ( Fig. 4F View FIGURE 4 ) pointed at apex, shorter than isthmus and longer than metaventral process; length ratio of mesoventral process, isthmus and metaventral process 2:4:1. Elytra slightly longer and wider than pronotum; elytron ( Fig. 4H View FIGURE 4 ) approximately 1.7 times as long as wide, pubescence directed posteriorly and postero-laterally; postero-lateral margin straight; hind wings fully developed, flabellum ( Fig. 4E View FIGURE 4 ) composed of about 6 long setose lobes. Legs slender and long, with pubescence and macrosetae; middle and hind tibia with different length of 2 spurs at apex; tarsal formula 4-5-5, length ratio of tarsomeres 19:20:20:44 (front tarsus); 23:24:26:25:42 (middle tarsus); 36:33:31:29:46 (hind tarsus); 1 empodial seta present, shorter than claw. Abdomen. Surface glossy, with imbricate microsculpture ( Fig. 5A–B View FIGURE 5 ); macrochaetal arrangement of tergites II–VI 01-02-12-12-12; male tergite VIII ( Fig. 6A View FIGURE 6 ) with 4 macrosetae on each side of midline, posterior margin subtruncate; male sternite VIII ( Fig. 6B View FIGURE 6 ) with 8 macrosetae on each side of midline, posterior margin subtruncate, with long marginal setae; posterior margin of female tergite VIII ( Fig. 6C View FIGURE 6 ) truncate; female sternite VIII ( Fig. 6D View FIGURE 6 ) with 6 macrosetae on each side of midline, posterior margin convex, very slightly prolonged, with long marginal setae, minute setae present in median region.

Aedeagus. Median lobe ( Fig. 6E–F View FIGURE 6 ) ovate, apical process constricted in basal region and pointed apically in ventral view; apical process more or less foot shape, sharply bent ventrad in lateral view. Apical lobe of paramere ( Fig. 6G View FIGURE 6 ) elongate and dilated apically, with four setae; b-seta longest, the other setae short, subequal in length. Spermatheca. S-shaped; bursa elongate, with long and large umbilicus; duct recurved ( Fig. 6H View FIGURE 6 ).

Type material. Holotype, labeled as follows: ‘ Gangwon Prov., Jeongseon-gun, Jeongseon-eup, Joyang-river , N37°23'1.5" E128°38'41.8" 306 m, 27 V 2009, YH Kim, JH Song, near stream’ GoogleMaps . Paratypes, 17 exx., same data as holotype.

Distribution. Korea (South).

Remarks. This species is very similar to H. longula (Heer) in external form but can be distinguished by the body more flattened dorso-ventrally, antenna paler, antennomere 2 slightly longer than 3, and the form of aedeagus and the shape of spermatheca (see fig. 8 in Yosii & Sawada 1976). All specimens were collected near a stream by the Joyang river.