Leiodes naraharai, 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 : 86-90

18. Leiodes naraharai sp. nov.

Japanese name: Narahara-ô-tamakinokomushi ( Figs. 55–57 , 115 )

Type locality. Japan, Ryukyus, Kagoshima Pref., Amami-Ôshima Is., Santarô-tôge Pass.

Type material. JAPAN: RYUKYUS: HOLOTYPE, ♂, Kagoshima Pref., Amami-Ôshima Is., Santarô-tôge Pass, 24– 27.ii.2010, S. Nomura leg. ( FIT) ( MNHAH). PARATYPES: 1♂, Kagoshima Pref., Amami-Ôshima Is., Mt.Yuwandake , 24–27.ii.2010, S. Nomura leg. ( FIT) ( FUFJ) ; 1♀, Kagoshima Pref., Amami-Ôshima Is., Yamato Village , 18.iii.2010, T. Lackner leg. ( JCHE) ; 1 ♂, Okinawa Pref., Okinawa Is., Oku , 30.i.2003, H. Irei leg. ( FUFJ) ; 1 ♀, Okinawa Pref., Okinawa Is., Kunigami Village, Aha , 4.-17.ii.2009, K. Sugino leg. ( MT) ( FUFJ) ; 3 ♂♂, 2 ♀♀, Okinawa Pref., Okinawa Is., Kunigami Village, Ie–Rindô , 13.–22.ii.2004, S. Nomura leg. ( FIT) ( FUFJ) ; 1 ♂, Okinawa Pref., Okinawa Is., Kunigami Village, Mt. Nishimedake , 13.–22.ii.2004, S. Nomura leg. ( FIT) ( FUFJ) .

Diagnosis. Body 2.5–3.0 mm long, ca. 1.7× as long as wide. Elytra bicolored. Each elytron with nine distinct rows of punctures and a subhumeral row ca. as long as 1/4 or 1/3 of elytral length. Mesoventrite without distinct excavation between median carina and transverse carina. Median carina of mesoventrite low. Mesotibiae without distinct sexual dimorphism. Metafemora sexually dimorphic. Male metatibiae feebly curved. Female abdominal sternite 8 with a spiculum ventrale.

Description. Measurement of holotype: Body length 3.0 mm; head 0.50 mm in length and 0.81 mm in width; pronotum 0.86 mm in length and 1.5 mm in width; elytra 1.9 mm in length and 1.7 mm in width.

Coloration. Dorsum shining; head brown; pronotum usually yellowish brown, rarely brown, sometimes blackish near posterior margin ( Figs. 55C, 55D ); elytra bicolored, yellowish brown with black stripes near elytral suture and lateral margins ( Figs. 55C, 55D ); antennomeres 1–6 brown; antennomere 8 dark reddish brown; antennomeres 7, 9, 10, and basal 3/5 of antennomere 11 blackish brown; apical 2/5 of antennomere light brown; legs brownish; procoxae, metacoxae, and all trochanters brown; remaining parts of legs light brown; mesoventrite, metaventrite and abdominal ventrites light brown.

Body 2.5–3.0 mm in length, ca. 1.7× as long as wide.

Head ca. 1.7× as wide as long, ca. 0.56× as long as and 0.58× as wide as pronotum, distinctly and densely punctate ( Fig. 55A ), usually bearing some large punctures ( Fig. 55A ); antennomeres 1–3 each longer than wide; antennomere 11 about as long as wide and oval; remaining antennomeres each wider than long ( Fig. 55E ); relative lengths of antennomeres 2 to 11 – 3.1: 3.3: 1.4: 1.6: 1.4: 2.6: 1.0: 3.4: 3.3: 4.4.

Pronotum ca. 1.7× as wide as long, ca. 0.43× as long as and 0.83× as wide as elytra, widest near base, simply and very feebly curved at posterior margin, distinctly and densely punctate, punctation similar to that on head ( Fig. 55A ).

Scutellum distinctly punctate.

Elytra ca. 1.1× as long as wide in dorsal view, widest ca. at basal 1/3 ( Fig. 55A ), not transversely strigose; each elytron with nine rows of punctures, bearing small number of large punctures and moderate number of very fine punctures between rows ( Fig. 55F ); row 9 invisible in dorsal view, subhumeral row ca. as long as 1/4 or 1/3 of elytral length ( Fig. 55B ); rows composed of puncture larger than those on pronotum ( Fig. 55A ); sutural stria fine, reaching from apex to ca. apical half of elytral length.

Metathoracic wings fully developed.

Mesoventrite strongly microreticulate, impunctate, almost glabrous, without distinct excavation between median carina and transverse carina ( Fig. 55G ); median carina of mesoventrite low ( Fig. 55G ); metaventrite without sexual dimorphism, sparsely pubescent, distinctly microreticulate except for almost smooth middle portion.

Legs sexually dimorphic on protarsi, mesotarsi, metafemora, and metatibiae; protibiae gradually and very feebly widening from base towards apex ( Figs. 56E, 56F ).

Male. Tarsomeres 2–4 of protarsi and mesotarsi a little expanded ( Fig. 56A ); metafemur with a large dorsal projection posteroapically ( Fig. 56G ); metatibiae feebly curved inwards, with some small robust spines along internal margins ( Fig. 56C ); abdominal sternite 8 weakly curved ( Fig. 57C ); aedeagus relatively robust ( Figs. 57A, 57B ); median lobe distinctly protuberant at apex in dorsal view ( Fig. 57A ), bluntly pointed apically in lateral view ( Fig. 57B ); each paramere pubescent at apex, bearing two apical setae, expanded in about apical 1/ 7 in dorsal view ( Fig. 57A ).

Female. Protarsi and mesotarsi slender ( Fig. 56B ); metafemora with a small dorsal projection posteroapically ( Fig. 56H ); metatibiae almost straight ( Fig. 56D ); abdominal sternite 8 with a spiculum ventrale at central point of anterior margin ( Fig. 57D ); coxites and stylus as shown in Fig. 57E .

Morphological variability. Leiodes naraharai sp. nov. shows intraspecific variation of dorsal coloration ( Figs. 55C, 55D ). The differences do not correlate to geographic region nor to the body size.

Differential diagnosis. Leiodes naraharai sp. nov. is similar to L. osawai Nakane, 1963 in having a bicolored dorsum, but can be distinguished from it by the oval body shape ( Fig. 55A ) and the mesoventrite without an excavation between the median carina and transverse carina ( Fig. 55G ). In contrast, L. osawai has a cylindrical body shape ( Fig. 87A ) and mesoventrite with a distinct excavation ( Fig. 87I ). Leiodes naraharai sp. nov. is also similar to L. bicolor (Fairmaire, 1858) inhabiting Europe and the Russian Far East by having a bicolored dorsum, but can be separated from it by having the median lobe protuberant apically ( Fig. 57A ). In contrast, L. bicolor has the median lobe rounded at the apex.

Etymology. The species name is dedicated to a prefectural governor Shigeru Narahara (1834–1918) who contributed to the modernization of Okinawa Island.

Distribution. Japan: Ryukyus (Amami-Ôshima and Okinawa Islands).

Figures

Fig. 55. Leiodes naraharai sp. nov.A – body, dorsal view; B – ditto, lateral view; C and D – dorsal color; E – antenna; F – elytral punctures; G – mesoventrite, lateral view. Scale I: 1 mm for A and B; II: 0.5 mm for E; III: 0.2 mm for G.

Fig. 56. Leiodes naraharai 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: 0.5 mm for C and D; III: 0.2 mm for E and F; IV: 0.2 mm for G and H.

Fig. 57. Leiodes naraharai sp. nov.A – aedeagus, dorsal view; B – ditto, lateral view; C – male abdominal sternite 8; D – female abdominal sternite 8; E – coxite and stylus. Scale I: 0.5 mm for A and B; II: 0.2 mm for C and D; III: 0.1 mm for E.

Fig. 115. Distribution of Leiodes naraharai group: (●) L. shuheii sp. nov. (■) L. naraharai sp. nov.

Fig. 87. Leiodes osawai Nakane, 1963.A – body, dorsal view; B – ditto, lateral view; C and D – dorsal color; E and F – lateral color; G – antenna; H – elytral punctures; I – mesoventrite, lateral view. Scale I: 1 mm for A and B; II: 0.5 mm for G; III: 0.5 mm for I.