Leiodes hijikatai, Hoshina, 2012

Hoshina, Hideto, 2012, Review of the tribes Sogdini and Leiodini from Japan and North Chishima Islands. Part II. Genera Hydnobius and Leiodes (Coleoptera: Leiodidae), Acta Entomologica Musei Nationalis Pragae (suppl. 1) 52, pp. 1-168 : 72-75

14. Leiodes hijikatai sp. nov.

Japanese name: Hijikata-ô-tamakinokomushi ( Figs. 44–46 , 114)

Type locality. Japan, Honshu, Tokyo Pref., Okutama Town, Nippera, Mt. Kintaisan (alt. 1300 m).

Type material. JAPAN: HONSHU: HOLOTYPE, ♂, Tokyo Pref., Okutama Town, Nippera, Mt. Kintaisan (alt. 1300 m), 3.xi.2006, H. Kamezawa leg. ( MNHAH). PARATYPE: 1 ♂, Nagano Pref., Tone Village, near Kuribara-gawa River , 12.x.1996, S. Hatsushiba leg. ( FUFJ).

Diagnosis. Body 2.9–3.0 mm long, ca. 1.7× as long as wide. Dorsum light brown. Antennal club dark reddish brown. Elytra densely, irregularly and coarsely punctate. Mesoventrite with one distinct excavation between median carina and transverse carina. Median carina of mesoventrite low. Metafemur with a distinct ventral rectangular projection posteroapically. Metatibiae weakly or strongly curved.

Description. Measurements of holotype: Body length 3.0 mm; head 0.41 mm in length and 0.83 mm in width; pronotum 0.83 mm in length and 1.4 mm in width; elytra 1.9 mm in length and 1.7 mm in width.

Coloration (based on the holotype only as the paratype is teneral). Dorsum shining and unicolor, light brown; antennomere 1 brown; antennomeres 2–6 and 8 reddish brown; remaining antennomeres dark reddish brown; legs brownish; trochanter reddish brown; tarsi brown; remaining parts of legs light brown; mesoventrite, metaventrite, and abdominal ventrites light brown.

Body 2.9–3.0 mm in length, ca. 1.7× as long as wide.

Head ca. 2.1× as wide as long, ca. 0.48× as long as and 0.58× as wide as pronotum, distinctly and densely punctate ( Fig. 44A ); antennomeres 1–4 each longer than wide; antennomere 11 about as long as wide; remaining antennomeres each wider than long; antennomere 11 oval ( Fig. 44C ); relative lengths of antennomeres 2 to 11 – 2.8: 3.6: 2.3: 1.9: 1.6: 2.7: 1.0: 2.9: 2.7: 5.1.

Pronotum ca. 1.7× as wide as long, ca. 0.44× as long as and 0.85× as wide as pronotum, widest at base, simply and very feebly curved at posterior margin, distinctly and densely punctate, punctation similar to that on head ( Fig. 44A ).

Scutellum minutely punctate.

Elytra ca. 1.1× times as long as wide in dorsal view, widest ca. at basal 2/5 ( Fig. 44A ), not transversely strigose, densely, irregularly and coarsely punctate ( Figs. 44A, 44B, 44D ); most punctures of elytra a little larger than those on head and pronotum ( Fig. 44A ); sutural stria fine, reaching from apex to ca. apical half of elytral length.

Metathoracic wings fully developed.

Mesoventrite strongly microreticulate, impunctate, almost glabrous, with a distinct excavation between median carina and transverse carina ( Fig. 44E ); median carina of mesoventrite low ( Fig. 44E ); metaventrite sparsely pubescent, strongly microreticulate except for almost smooth middle portion.

Protibiae gradually and very feebly widening from base towards apex ( Fig. 45D ); tarsomeres 2–4 of protarsi and mesotarsi expanded ( Fig. 45A ); metafemur with a distinct ventral rectangular projection ( Figs. 45B, 45C ) and a small dorsal projection posteroapically ( Fig. 45E ); metatibiae bearing less than ten small robust spines at about basal 1/3 of internal margins, weakly curved in holotype ( Fig. 45C ) and strongly curved in paratype ( Fig. 45B ).

Abdominal sternite 8 moderately curved ( Fig. 45F ); aedeagus slender ( Figs. 46A, 46B ); median lobe weakly expanded laterally in apical half of lateral margins and feebly curved at apex in dorsal ( Fig. 46A ), moderately curved in lateral view ( Fig. 46B ); each paramere bearing two apical setae and one transparent slender lobe ( Fig. 46A ); inner sac without distinct sclerites ( Fig. 46C ).

Female. Unknown.

Differential diagnosis. Leiodes hijikatai sp. nov. is similar to L. araii sp. nov. in the form of the elytral punctures but can be distinguished from it by having dark reddish brown antennal club and having the metafemur with a distinct ventral posteroapical projection ( Figs. 45B, 45C ). In contrast, L. araii sp. nov. has the antennae almost uniformly brown and the metafemora weakly expanded posteriorly ( Figs. 40C, 40D ). Leiodes hijikatai sp. nov. is also similar to the European L. punctulata (Gyllenhal, 1810) by the irregularly punctate elytra and the mesoventrite bearing an excavation, but can be separated from it by having the lateral margins of the median lobe feebly curved at the apex in dorsal view ( Fig. 46A ). In contrast, L. punctulata has the median lobe protuberant apically.

Etymology. This species is dedicated to a very popular samurai Toshizô Hijikata (1835–1869) who was born in the Tama Region in which the type locality of this species is situated.

Distribution. Japan: Honshu (Tokyo and Nagano Prefectures).

Figures

Fig. 44. Leiodes hijikatai sp. nov.A – body, dorsal view; B – ditto, lateral view; C – antenna; D – elytral punctures; E – mesoventrite, lateral view. Scale I: 1 mm for A and B; II: 0.5 mm for C; III: 0.5 mm for E.

Fig. 45. Leiodes hijikatai sp. nov. A – male fore leg, ventral view; B – male hind leg of paratype, ventral view; C – ditto of holotype; D – male protibia, dorsal view; E – male metafemur, dorsal view; F –male abdominal sternite 8. Scale I: 0.5 mm for A; II: 0.5 mm for B and C; III: 0.2 mm for D; IV: 0.2 mm for E; V: 0.5 mm for F.

Fig. 46. Leiodes hijikatai sp. nov.A – aedeagus, dorsal view; B – ditto, lateral view; C – inner sac, dorsal view. Scale I: 0.5 mm for A and B; II: 0.1 mm for C.

Fig. 40. Leiodes araii sp. nov.A – male fore leg, ventral view; B – female fore leg, ventral view; C – male hind leg, ventral view; D – female hind leg, ventral view; E – male protibia, dorsal view; F – female protibia, dorsal view; G – male metafemur, dorsal view; H – female metafemur, dorsal view. Scale I: 0.5 mm for A and B; II: 1 mm for C and D; III: 0.2 mm for E and F; IV: 0.2 mm for G and H.