Scaphidium morimotoi Löbl, 1982

Ogawa, Ryo, Matsuo, Susumu, Hoshina, Hideto & Maeto, Kaoru, 2016, Allopatric color forms of Scaphidium morimotoi Löbl, 1982 (Coleoptera, Staphylinidae, Scaphidiinae) endemic to the Amami Islands, the Ryukyus, Japan, Zootaxa 4175 (1), pp. 67-74 : 70

Scaphidium morimotoi Löbl, 1982

[Japanese name: Amami-deokinokomushi] ( Figs. 3 a–d, 4a–j, 5a–d)

Scaphidium takahashii Shirôzu & Morimoto, 1963: 64 Scaphidium insulare: Nakane, 1963: 78 , pl. 39, Fig. 16. [misidentification] Scaphidium morimotoi Löbl, 1982: 101 .

Scaphidium sp.: Morimoto, 1985: 255.

Scaphidium amamiense Hoshina & Morimoto, 1999: 90 . Syn. nov.

Diagnosis. Body almost black. Pronotum usually with reddish-brown fasciae along apicolateral margin, but its fasciae sometimes extending from apicomedian to basal transverse stria. Elytra usually each with two transverse reddish fasciae at subbasal and subapical area; both fasciae narrowed in middle, touching striae of lateral margin, but sometimes absent; subbasal fasciae not reaching sutural striae, larger than subapical one, more strongly narrowed in middle. Legs reddish-brown. Pronotum wider than long, gradually curved to apex at lateral sides. Internal sac with complex sclerites ( Figs. 4 a–h, 5a, b).

Supplemental description of genitals. Male. Everted internal sac as Figs. 4 a–h; ventral swelling almost square, with reversed v-shaped sclerite at basal area; dorsal swelling shaped like wings of butterfly, with a pair of small swellings basally. Tip studded sclerites with opening of ejaculatory duct at center.

Female. Female genitalia with a pair of spermathecae and a vaginal plate ( Fig. 4 c, d); vaginal plate curved laterally and turned ventrally, with spines-structure on lateral side; spermathecae connected under vaginal plate.

Coloration. The specimens from Yoro-shima usually had an almost completely black body ( Fig. 2 a), but sometimes had reddish fasciae along apicolateral margin of pronotum and subapical part of each elytron ( Fig. 2 b). Meanwhile, the specimens from the other islands were consistently well marked: they had fasciae along apicolateral margin of pronotum and on subbasal and subapical parts of each elytron ( Fig. 2 c, d).

Measurements. [Amami-ôshima and Kakeroma-jima] Male (n = 6). Length (PL+EL): 3.53–4.33 mm, PW: 2.20–2.70 mm, EW: 2.33–2.93 mm, HW: 0.89–1.02 mm, ID: 0.20–0.24 mm, PL/PW: 0.63–0.68, EL/EW: 0.85– 0.92. Female (n = 13). Length (PL+EL): 3.77–4.43 mm, PW: 2.33–2.77 mm, EW: 2.47–3.00 mm, HW: 0.89–1.04 mm, ID: 0.20–0.24 mm, PL/PW: 0.61–0.70, EL/EW: 0.86–0.93. Approximate ratio of length (width) of each antennomere from base to apex as follows (n = 1): 1.2 (0.4): 0.7 (0.3): 1.0 (0.3): 1.0 (0.2): 0.9 (0.3): 0.7 (0.3): 0.8 (0.5): 0.7 (0.4): 0.8 (0.6): 0.8 (0.7): 1.1 (0.8). [Yoro-shima] Male (n = 5). Length (PL+EL): 3.77–4.13 mm, PW: 2.37–2.63 mm, EW; 2.47–2.77 mm, HW: 0.89–0.98 mm, ID: 0.20–0.22 mm, PL/PW: 0.62–0.67, EL/EW: 0.87–0.93. Female (n = 4). Length (PL+EL): 3.77–4.20 mm, PW: 2.33–2.57 mm, EW: 2.47–2.53 mm, HW: 0.93– 0.98 mm, ID: 0.20–0.27 mm, PL/PW: 0.64–0.66, EL/EW: 0.87–0.92. Approximate ratio of length (width) of each antennomere from base to apex as follows (n = 1): 1.1 (0.4): 0.6 (0.3): 1.0 (0.3): 1.1 (0.2): 0.9 (0.3): 0.7 (0.3): 0.8 (0.5): 0.8 (0.4): 0.8 (0.6): 0.8 (0.7): 1.1 (0.7).

Type material examined. Holotype of Scaphidium takahashii Shirôzu & Morimoto, 1963 (nec Miwa & Mitono, 1943), ♂, Yoro-shima , Is., Amami Islands, 11. III. 1958, M. Takahashi leg. ( KUEC) ; Holotype of Scaphidium amamiense Hoshina & Morimoto, 1999 , ♂, Mt. Yuwandake , Amami-ôshima I., Amami Is., 8. IV. 1996, H. Hoshina leg. ( KUEC) .

Additional materials examined. [Amami-ôshima] 3♂♂ 3♀♀, Mt. Yuidake , 29. IV. 2009, R. Ogawa leg. ; 2♀, same data above, but 6. V. 2009 ; 2♀, Tatsugô-chô , 8. V. 2009, R. Ogawa leg. ; 1♀, Mt. Yuwandake , 5. V. 1977, M. Sakai leg. ; 1♂ 3♀♀, Chûou-rindô , Amami-City, 4. VI. 2009, Y. Okahana leg. [Kakeroma-jima] 1♀, Mt. Kanyûyama, Is. Kakeroma-jima, 4. VI. 2009, S. Matsuo leg. ; 2♂, same data above, but R. Ogawa leg. [Yoro-shima] 1♂, Mt. Ôkachiyama , 1. V. 2009, R. Ogawa leg ; 3♂, Mt. Ôkachiyama , 1. V. 2009, S. Matsuo leg. ; 1♀, Mt. Ôkachiyama , 2. V. 2009, S. Matsuo leg. ; 3♀ 1♂, Mt. Ôkachiyama , 2. V. 2009, R. Ogawa leg. All specimens will be deposited at EUMJ.

Distribution. Japan: Amami Islands (Amami-ôshima, Kakeroma-jima, Yoro-shima, Tokunoshima).

Figures

FIGURE 2. Phylogenetic relationships of Scaphidium morimotoi with three related species. Maximum likelihood bootstrap values> 50 % are shown above branches. Scale: differences of 5 % of base pairs are shown.

FIGURE 3. Habitus of Scaphidium morimotoi. a, b, Specimens from the island Yoro-shima (left, dorsal view; right, lateral view); c, d, specimens from the island Amami-ôshima (left, dorsal view; right, lateral view); a, c, d, female; b, male.

FIGURE 4. Everted internal sac and antennae of Scaphidium morimotoi. a – d, i, Specimen from the island Yoro-shima; e – h, j, specimen from the island Amami-ôshima. a – d, e – h, Everted internal sac; a, e, ventral view; b, f, lateral view; c, g, dorsal view; d, h, apical view (from apex toward base); i, j, antennae of female. Scales: 0.5 mm.