Andrikothelyna naomichii, Nozaki, 2023

Nozaki, Tsubasa, 2023, Taxonomy of the genus Andrikothelyna Pace, 2000 (Coleoptera: Staphylinidae Aleocharinae), with description of three new species from Taiwan and Japan, Zootaxa 5264 (1), pp. 64-76 : 71-73

Andrikothelyna naomichii sp. nov.

( Figs 4, 8 , 31–36 , 38 )

(Japanese name: tsuji-toguro-hanekakushi)

Diagnosis. Andrikothelyna naomichii sp. nov. can be easily distinguished from any other species of the genus owing to its orange-colored body. In addition, characteristics unique to this new species are as follows: elytra bearing weak granules along the suture ( Figs 4, 8 ) and hardly carinate near the lateral margin; median lobe of male aedeagus ( Fig. 34 ), bulb and flagellum not coiled; velum of paramere wing-shaped ( Fig. 35 ); basal part of female spermatheca rough and not bent ( Fig. 36 ).

Material examined. Holotype. Male, “ ṖDZẹƃḇffiǎḛff / Mt. Maese-dake, Ishigaki, / [GPS] N: 24. 37, E: 124.15 / Ishigaki Is. , Ryûkyû, JAPAN. / 30-31. V. 2021. N. Tsuji leg.” ( KUM). Paratypes. JAPAN: Ryukyu: Okinawa-ken: Ishigaki Is.: 2♂, 3♀, same data as holotype, ( KUM); 6♂, 8♀, same locality, T. NOZAKI & K. Goino leg., 29.III.2022, T. Nozaki & K. Goino leg. ( KUM, one pair for cI);

Description. Body ( Figs 4, 8 ) small; dorsal surface less glossy, weakly reticulated.

Color. Body orange, abdomen reddish brown; antennae orange with segments I to III pale yellow; maxillary palpi, forelegs yellow, meso- and metalegs reddish orange.

Head. Eyes large, as long as 1/4 of head; infraorbital carina developed. Antennae ( Fig. 4 ) longer than head and pronotum combined; segments II–X dilated; segments I–III elongate, segments IX–X distinctly transverse; segment XI elongate, round at apex; approximate relative length of segments from basal to apex: 18: 19: 16: 10: 10: 10: 11: 11: 11: 11: 29.

Thorax. Pronotum, lateral margin round; postero-lateral angle obtuse. Elytra, postero-lateral angle strongly sinuate; longitudinal row of granules along suture weak ( Figs 4, 8 ); near lateral margin hardly carinate. Mesoventral process, apex varying truncated to round.

Abdomen. Posterior margin of tergite VIII ( Fig. 31 ) with 4–6 short teeth, apex of each tooth with microseta; medial grub deepest; other grubs varying and frequently becoming asymmetric.

Legs. Moderately slender in general; tibiae covered with fine setae. Approximate relative length of mesotarsal segments from basal to apex: 28: 12: 10: 34, and that of metatarsal segments: 37: 11: 10: 10: 36.

Male. Tergite VII with two posteromedial granules; posterior margin of sternite VIII ( Fig. 32 ) round and smooth. Median lobe of aedeagus ( Fig. 34 ) length about 0.47 mm, elongate, bulb itself not coiled; flagellum not coiled, base oar shaped. Paramere ( Fig. 35 ), velum wing-shaped; apical lobe of paramerite short and subtrapezoid.

Female. Tergite VII without posteromedial granule; posterior margin of sternite VIII ( Fig. 33 ) varying round to shallowly emarginated. Spermatheca ( Fig. 36 ), apical part subspherical; basal part unsmooth.

Measurements (n = 10). BL ≈ 1.56–2.16; AL, 0.59–0.65; PL, 0.32–0.36; PW, 0.62–0.69; EL, 0.34–0.39; EW, 0.69–0.76; HTL, 0.39–0.44; PW/PL, 1.87–2.02; EW/EL, 1.86–2.26; AL/PL, 1.73–1.95.

Variation. Distinct sexual dimorphism was evident in the posteromedial granules of tergite VII. Intra-species variations exist in the following characters: teeth number and shape of the posterior margin of tergite VIII; the apical shape of the mesoventral process; and the posterior margin of female sternite VIII.

Etymology. The specific name is dedicated to the first person to discover the new species, Mr. Naomichi Tsuji (KUM, Fukuoka).

Distribution. Japan: Ryukyu (Ishigaki Island).

Bionomics. Individuals of the type series were collected from freshly dead or weakened branches on the living trunk of the Japanese bay tree, Machilus thunbergii Siebold et Zucc. ( Fig. 37 ) and observed walking on these branches at night ( Fig. 38 ).

Figures

FIGURES 1–8. Habitus of Andrikothelyna spp. 1, 5―Holotype of Andrikothelyna rubiginosa sp. nov., female; 2, 6―Holotype of Andrikothelyna limbata sp. nov., male (Kyushu); 3, 7―Andrikothelyna limbata sp. nov. male (Ishigaki Is.); 4, 8―Holotype of Andrikothelyna naomichii sp. nov. male.

FIGURES 31–36. Andrikothelyna naomichii sp. nov. 31―abdominal tergite VIII, male; 32―abdominal sternite VIII male; 33―abdominal sternite VIII female; 34―median lobe of male aedeagus; 35―Paramere of male aedeagus; 36―female spermatheca.

FIGURES 37–38. Habitat of Andrikothelyna naomichii sp. nov. 37―branches of the Japanese bay tree, Machilus thunbergii from which the species is collected; 38―a living individual at night (photo by Kyotaro Goino).