Limnebius (s.str.) agnieszkae, Przewoźny, Marek, Greń, Czesław & Jäch, Manfred A., 2016

Przewoźny, Marek, Greń, Czesław & Jäch, Manfred A., 2016, Limnebius (Limnebius) agnieszkae sp. n. from the Crimean Peninsula (Coleoptera: Hydraenidae), Zootaxa 4184 (2), pp. 391-394 : 392

Limnebius (s.str.) agnieszkae sp. n.

( Figs. 1–3)

Type material. Holotype, male: “ Ukraina, Krym XQ03 [UTM] Hurzuf (Гурзуф), Avunda river [44°33'2''N 34°15'49''E] 13.06.2013 leg. Czesław GREŃ ” ; “Holotype Limnebius agnieszkae sp. n. des. M. Przewoźny, C. Greń & M.A. Jäch, 2016” [red printed label] (USMB). Paratypes: 1 male: “ UKRAINA, Krym, WQ73 [UTM] River Kokkozka Sokolinoe (Соколиное, Река Коккозка) [44°33'42''N 33°57'12''E] 13.06.2013, leg. Czesław GREŃ ” ( CCG) ; 6 spec. (3 males, 3 females): Ukraine, Crimea, Hurzuf , stream, 3.VII.2000, leg. S.K. Ryndevich ( CRB, NMW) ; 1 female: Ukraine, Crimea, Alushta, Ulu-Uzen River , 9.VII.2000, leg. S.K. Ryndevich ( NMW). Each paratype with red printed paratype label.

Diagnosis. Limnebius agnieszkae sp. n. is a member of the Limnebius furcatus subgroup of the L. parvulus species group (sensu Jäch 1993). It can be distinguished from Limnebius stagnalis Guillebeau, 1890 only by the aedeagus ( Fig. 3).

Description. Habitus as in Figs. 1–2. Measurements: Males: Body length (without abdomen) 1.85–2.00 mm (holotype: 2.00 mm), width 0.92–1.02 mm (holotype: 1.02 mm). Females: Body length (without abdomen) 1.86–1.94 mm, width 1.00– 1.06 mm. The paratype from River Kokkozka deviates considerably: length 1.64 mm, width 0.78 mm.

Body oval, dorso-ventrally flattened, black, lateral sides slightly paler, dark brown, antennae and legs also dark brown, hypomera and epipleura dark brown. Pronotum smooth and glabrous, usually sparsely micropunctate, laterally faintly microreticulate. Elytra distinctly microreticulate, sparsely micropunctate, punctures more or less the same size as on pronotum. Elytral apex weakly rounded, lateral hind angles distinctly rounded. Pronotum and elytra sparsely covered with pale setae. Ventral surface covered with short adpressed pale setae.

Male. Male ventrite VI with a dense fringe of long setae, surface with distinct microreticulation.

Aedeagus ( Fig. 3) 500–560 µm long. In size and shape it is very similar to that of Limnebius stagnalis (520–580 µm long) (see Jäch 1993: Fig. 75). Apical median appendix of main piece with a transverse terminal bar, which is distinctly excised on right side. Due the variability of the aedeagi, especially of the new species, there seem to be only very few reliable diagnostic characters: in L. stagnalis 1) basal part of apical median appendix slightly more slender at base, and 2) slightly more distinctly curved to dorsal side and to right side; 3) apical part of excision of terminal transverse bar more strongly hooked (claw-like) (arrow “a” in Fig. 3); 4) pseudoparamere more distinctly angulate (or at least more strongly curved) laterally (arrow “b” in Fig. 3).

The left branch of the terminal bar is usually, but not always, longer in L. stagnalis .

Variability. Externally, both species are quite variable, especially with regard to the pronotal punctation, which is hardly visible in some specimens.

The specimen from Sokolinoe deviates not only in the small body size, also its aedeagus is much shorter: 460 µm long. The punctation on pronotum and elytra is hardly visible in this specimen.

The left apical corner of the left paramere is highly variable and cannot be used to distinguish L. stagnalis and the new species.

Etymology. This species is dedicated to Agnieszka Przewoźna, wife of the first author. The specific epithet is a substantive in the genitive case.

Habitat. All specimens were found in running water in the Crimean Mountains. The type locality near Hurzuf is a small mountain stream (Avunda Rivulet), 1.0– 1.5 m wide, with a fast current, about several dozen cm deep, with a rocky bottom sparsely covered with moss. Additional water beetle species collected in this locality: Agabus dilatatus (Brullé, 1832) (26 spec.), Ilybius chalconatus (Panzer, 1797) (4 spec.), Hydroporus discretus Fairmaire & Brisout, 1859 (3 spec.), H. dobrogeanus Ieniştea, 1962 (1 spec.), H. planus Fabricius, 1781 (2 spec.), H. pubescens (Gyllenhal, 1808) (6 spec.), H. transgrediens Gschwendtner, 1923 (1 spec.), Helophorus brevipalpis Bedel, 1881 (2 spec.), H. flavipes Fabricius, 1792 (1 spec.), and Laccobius obscuratus aegaeus Gentili, 1974 (26 spec.). The locality at Sokolinoe ( Fig. 4 ) is a mountain river, about 12 m wide, up to 60 cm deep, with rocky bottom and dense mats of aquatic moss. Additional water beetles collected at this locality: Agabus bipustulatus (Linnaeus, 1767) (1 spec.), Helophorus brevipalpis Bedel, 1881 (55 spec.), H. flavipes Fabricius, 1792 (5 spec.), Laccobius gracilis Motschulsky, 1855 (6 spec.), L. simulatrix Orchymont, 1932 (21 spec.), Limnebius atomus (1 spec.), L. myrmidon Rey, 1883 (33 spec.) [first record for Ukraine!], and Pomatinus substriatus (Müller, 1806) (1 spec.).

Distribution. Limnebius agnieszkae sp. n. is known from three localities in the mountains of the southern part of the Crimean Peninsula.

Figures

FIGURE 4. River Kokkozka, at Sokolinoe.