Cercyon (Clinocercyon) primoricus, Ryndevich & Prokin, 2017

Ryndevich, Sergey K. & Prokin, Alexander A., 2017, Two new species of Cercyon (Clinocercyon) from Russian Far East (Coleoptera: Hydrophilidae), Zootaxa 4300 (1), pp. 125-134 : 129-130

Cercyon (Clinocercyon) primoricus sp. nov.

( Figs. 14–25 )

Type locality: Russia, Far East, South of Primorsky Krai, Lazovsky State Nature Reserve , Glazkovka.

Type material: Holotype: male, Lazovskiy zapovednik [Lazovsky State Nature Reserve], Glazkovka, 8– 20.08.2007, leg. V. Shokhrin, [in Russian], ( ZISP) . Paratypes (16): 1 male, 6 females, Yu. Primor’e , Khasanskiy r- n, okr. bukh. Perevoznaya [ South Primorye , Khasan district, near Perevoznaya bay], 25.VI.1990, na gribakh [on mushrooms], leg. K. Makarov [in Russian], ( MPU, CSR) ; 1 male, 1 female, Rossiya , Primorskiy kr., Lasovskiy r-n, Glazkovka [ Russia, Primorsky Krai, Lasovskiy district, Glazkovka], 17.VII.2003, leg. Yu. Sundukov, [in Russian], ( NMPC, MPU) ; 2 females, Yu. Primor’e , Ussuriyskiy zapovednik [S. Primorye, Ussuriyskiy State Nature Reserve], 14.VII.1987, leg. S. Kurbatov [in Russian] (CSK) ; 1 female, Yu. Primor’e , Khasanskiy r-n, Kedrovaya Pad' [ South Primorye , Khasan district, Kedrovaya Pad' Sate Nature Reserve], 26.VII.1987, leg. S. Kurbatov [in Russian] ( CSR) ; 1 male, Yu. Primor’e , Kamenushka bliz Ussuriysk [ South Primorye , river Kamenushka near Ussuriysk], 15.VI.1984, leg. Nikitsky [in Russian] ( ZMMU) . 1 male, 2 females, Vladivostok , botsad [ Russia, Vladivostok, botanical garden], 27.VI.1990, leg. I. Melnik [in Russian] ( ZISP, CSR) .

Differential diagnosis. Body broadly oval. Dorsal side without microsculpture ( Fig. 14 ). Total colour brownish-yellow. Maxillary palpomeres yellow or brownish-yellow, palpomere 4 ca. 1.4× as long as palpomere 3 ( Figs. 14, 15 ). Preepisternal plate very elongate, ca. 5.6–7.2× as long as wide, metaventrite without femoral lines. Femora without microsculpture ( Fig. 15 ). Median projection of sternite 9 very narrow with large membranous part, phallobase longer than parameres, ca. 1.7× as long as parameres. Paramere with parallel sides cut along the inner edge at apex, with numerous very short setae, apex of parameres membranous with very short seta. Median lobe widest near middle, slightly narrowing apically, apex pointed and curved ( Figs. 18–25 ).

Description. Form and Colour. Body broadly oval ( Fig. 14 ), length 2.0– 2.4 mm, width 1.3–1.7 mm (holotype length 2.3, width 1.6). General colour of body brownish-yellow. Antennae yellowish except for brownish-yellow club. Maxillary palpomeres yellow or brownish-yellow. Epipleura colour as general body color. Ventral surface brownish-yellow, preepisternal plate darker. Legs yellowish-brown, tarsi paler ( Fig. 15 ). Head. Dorsal side without microsculpture with dense moderately coarse punctures. Anterior margin of clypeus narrowly rimmed. Eyes small, somewhat protruding, interocular distance ca. 6.1–6.3 × as wide as one eye in dorsal view. ( Fig. 14 ). Mentum glabrous, ca. 1.9–2.0× as wide as long, densely and coarsely punctate, slightly depressed anteromedially ( Fig. 15 ). Antennae with 9 antennomeres, scapus ca. 1.2× as long as antennomeres 2–5 combined, club compact. Maxillary palpomere 2 strongly swollen, palpomere 4 ca. 1.4× as long as palpomere 3 in length ( Figs. 14, 15 ). Thorax. Pronotum ca. 2.6× as wide as long. Pronotal punctation similar to that on head. Lateral margins of pronotum narrowly rimmed, the rim overlapping anterior and posterior corners, anterior and posterior margin without rim. Prosternum with strong longitudinal carina medially; antennal groove distinct, medium large, rounded laterally ( Fig. 15 ). Preepisternal plate very elongate, ca. 5.6–7.2× as long as wide, widest in anterior part near middle or in middle ( Fig. 15 ). Metaventrite with raised glabrous, clear sparsely punctate median pentagonal area; femoral lines absent. Elytra with 10 punctate striae, striae 1–5 very slightly impressed, striae 1–6, 9 reaching base, striae 7, 8 and 10 not reaching base. Elytral intervals flat. Ground punctures on intervals very fine ( Fig. 14, 16 ). Humeral bulge not distinct. Elytra and pronotum without hairs. Epipleura of elytra wedge-shaped, bent downwards ( Fig. 15 ). Femora with sparse and shallow punctures, without microsculpture ( Fig. 15 ), with distinct tibial groove. Tarsi with densely arranged white setae ventrally, first metatarsomere about as long as metatarsomeres 2–3 combined. Abdomen. Abdomen with five exposed ventrites, first ventrite distinct longer than other ventrites, ca. 1.6× as long as second, with distinct median longitudinal carina, fifth ventrite arcuate, not emarginate apically ( Fig. 15 ). Male genitalia ( Figs. 18–25 ). Median projection of sternite 9 very narrow with large membranous part, median portion shorter than lateral struts ( Figs. 21, 25 ). Phallobase longer than parameres, ca. 1.7× as long as parameres, asymmetrical basally. Parameres with parallel sides cut along the inner edge at apex, with numerous very short setae ( Figs. 18, 22 ). Apex of parameres membranous with very short seta ( Fig. 23 ). Median lobe widest near middle, slightly narrowing apically, with short ароdemes ( Figs. 19, 24 ), apex pointed and curved; gonopore small, situated subapically ( Fig. 20 ).

Variation. Some specimens have anterior and lateral sides of head slightly darker, brownish.

Etymology. The name reflects type locality, derived from derived from Primorye (physical-geographical region, including Primorsky Krai and southern (Trans-Amurian or Zaamurye part of the Khabarovsk Krai) (masculine).

Biology. Polysaprophagous, found in different decaying substances and on mushrooms.

Distribution. Russian continental Far East (Primorsky Krai).

Figures

FIGURES 14 – 17. Habitus of Cercyon primoricus sp. nov. 14: dorsal view; 15: ventral view; 16: lateral view; 17: metafemora.

FIGURES 18 – 25. Male genitalia of Cercyon primoricus sp. nov. 18, 22: phalobase and parameres; 23: apex of paramere; 19, 24: median lobe; 20: apex of median lobe; 21, 25: sternite 9. Scale bar = 0.5 mm.