Leiodes irregularis Portevin 1927

32. Leiodes irregularis Portevin, 1927

Japanese name: Etorofu-ô-tamakinokomushi (Figs. 6, 93–95, 109)

Liodes suturalis Portevin, 1927: 75.

Liodes irregularis Portevin, 1927: 76; HATCH (1929): 35; DAFFNER (1983): 87 (synonymized with Leiodes portevini); Perreau (2004): 196 (catalogue).

Liodes dichroa Portevin, 1927: 76; HATCH (1929): 36; DAFFNER (1983): 87 (synonymized with Leiodes portevini).

Liodes Grouvellei Portevin, 1927: 76; HATCH (1929): 36; DAFFNER (1983): 87 (synonymized with Leiodes portevini).

Liodes intermedia Portevin, 1927: 77; HATCH (1929): 36; DAFFNER (1983): 87 (synonymized with Leiodes portevini).

Leiodes portevini Hatch, 1929: 35 (substitute name for Liodes suturalis Portevin, 1927 which became a homonym of Leiodes suturalis Stephens, 1832); DAFFNER (1983): 86 (redescription).

Liodes elongate Portevin, 1943: 168; DAFFNER (1983): 87 (synonymized with Leiodes portevini).

Type locality. Japan, Hokkaido, Etorofu Is.

Type material. Not examined.

Additional material examined. JAPAN: HOKKAIDO: 1 ♀, Mt. Meakandake, 12.vii.1995, H. Hoshina leg.; 1 ♀, Mts. Daisetsu, Mt. Kurodake, 2.viii.1987, N. Yasuda leg.; 6 spec., Sapporo City, forests near Historical Museum of Hokkaido, 7.viii.2002, S. Hori leg.(FIT); 11 spec., 29.vi.2000, 6 spec., 19.vii.2000, 10 spec., same data as the former except for the date, 29.viii.2001; 1 spec., Ebetsu City, Nopporo Forest Park, x-xi.2005, T. Lackner leg. (JCHE); 7 spec., Kotohira, 14–27.vii.1999, S. Hori leg. (PT); 10 spec., Shirataki Village, Hirayama, 5.viii.1993, S. Hori leg. 5 spec., Rebun Town, Shiretoko, 18.vii.–1.viii.2001, S. Hori leg. (FIT); 1 ♀, Rishiri Is., Mt. Rishiri, 2.ix.1991, N. Yasuda leg. HONSHU: 1 ♂, 1 ♀, Gunma Pref., Tsumagoi Village, Mt.Asashiki, 24.vii.1979, K. Itô leg. (EUMJ); 1 ♀, Yamanashi Pref., Nirasaki City, Hôô-goya, 25.viii.1997, K. Hosoda leg.; 1♂, same locality, 15.viii.2000. Specimens preserved in FUFJ when not stated otherwise.

Diagnosis. Coloration. Dorsum almost unicolor or bicolored, showing multiple color variations (Figs. 93C, 93D, 93E, 93F, 93G); head, pronotum, and scutellum brown, dark brown or blackish brown; elytra brown, often with dark brown or blackish brown stripes near elytral suture (Figs. 93F, 93G); antennomeres 1–6 and 8 brown; antennomeres 7, 9, 10, and basal 3/5 of antennomere 11 dark brown; apical 2/5 of antennomere 11 light brown.

Body 2.4–4.0 mm long, ca. 1.8× as long as wide (Fig. 93A). Head densely and minutely punctate, often bearing some large punctures (Fig. 93A); antennomeres 1–3 each longer than wide; antennomeres 4 about as long as wide; remaining antennomeres each wider than long; antennomere 11 oval (Fig. 93H). Pronotum simply and very feebly curved at posterior margin and densely and minutely punctate (Fig. 93A). Elytra 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. 93I); row 9 invisible in dorsal view, subhumeral row as long as ca. 1/5 or 1/4 (Fig. 93B); rows composed of punctures larger than those of pronotum (Fig. 93A); sutural stria fine, reaching from apex to ca. apical half of the elytral length. Metathoracic wings fully developed. Mesoventrite without distinct excavation between median carina and transverse carina (Fig. 93J); median carina of mesoventrite low (Fig. 93J); metaventrite without sexual dimorphism. Legs indistinctly sexually dimorphic; protibiae gradually and very feebly widening from base towards apex (Figs. 94F, 94G); metafemur with a small dorsal projection posteroapically (Figs. 94H, 94I).

Male. Tarsomeres 2–4 of protarsi and mesotarsi feebly expanded (Fig. 94A); metatibiae very feebly curved inwards (Figs. 94C, 94D); abdominal sternite 8 weakly curved (Fig. 95D); aedeagus as shown in Figs. 95A, 95B; inner sac as shown in Fig. 95C.

Female. Protarsi and mesotarsi slender (Fig. 94B); metatibiae almost straight (Fig. 94E); abdominal sternite 8 with spiculum ventrale at central point of anterior margin (Fig. 95E); coxites and stylus as shown in Fig. 95F.

Morphological variability. The present species is distributed in both Hokkaido and Honshu (Fig. 109) and shows some regional morphological differences. One of the intraspecific variations is the dorsal color (Figs. 93C, 93D, 93E, 93F, 93G), and this difference does not correlate to regional populations. In contrast, the body size and male metatibiae have regional morphological differences. Most of the specimens collected from Hokkaido are less than 3 mm in length and the male metatibiae are very feebly curved inwardly (Fig. 94). On the contrary, specimens from Honshu are more than 3.5 mm in length and the male metatibiae are weakly curved (Fig. 94D).

Differential diagnosis. Leiodes irregularis is similar to L. iwakirii sp. nov. in having a small body, but can be distinguished from the latter by the mesoventrite without a distinct excavation (Fig. 93J) and abdominal sternite 8 being weakly curved (Fig. 95D). In contrast, L. iwakirii sp. nov. has the mesoventrite with a distinct excavation (Fig. 75E) and abdominal sternite 8 strongly curved (Fig. 76E).

Distribution. Japan: Hokkaido, Rishiri Is., South Chishima Islands (Etorofu Is.), and Honshu (Gunma Prefecture and Yamanashi Prefecture). New to Hokkaido, Rishiri Is., and Honshu.