Scleropteroides horridulus (Voss, 1958)

Huang, Junhao, Yoshitake, Hiraku, Zhang, Runzhi & Ito, Motomi, 2014, Taxonomic revision of the East Asian genus Scleropteroides Colonnelli, 1979 (Coleoptera, Curculionidae, Ceutorhynchinae), ZooKeys 437, pp. 45-86 : 51-58

Taxon classification Animalia Coleoptera Curculionidae

Scleropteroides horridulus (Voss, 1958) Figs 5, 6, 30-33, 38-39, 90-132, 134

Homorosoma horridula Voss, 1958: 67 (type locality: China, “Kuatun”) (incorrect original spelling). - Chûjô 1971: 34 (Is. Okinawa: Nago).

Homorosoma horridulum (mandatory correction, gender agreement): Chûjô and Voss 1960: 7 (in part; Is. Okinawa: Nago). - Colonnelli 2004: 34 (in catalog; China, Japan).

Rhytidosomus insulare Voss 1971: 54 (type locality: Japan, Is. Amami, Hatsuno) (incorrect original spelling).

Scleropteroides horridulus : Korotyaev et al. 2014: 99 (combination from Homorosoma ; Taiwan) (mandatory correction, gender agreement).

Scleropteroides insulare : Morimoto 1984: 316 (Amami, Okinawa); 1989: 514 (in checklist; Amami, Okinawa) (incorrect subsequent spelling).

Scleropteroides insularis : Yoshitake et al. 2004: 106 (in checklist).

Scleropteroides hypocrita : Colonnelli 2004: 34 (in part; not Hustache 1916).

Diagnosis.

This species differs from Scleropteroides hypocrita on the basis of the following characters: subapical part of the prothorax strongly constricted (Fig. 38); elytra with strongly prominent humeri, straightly convergent toward the subapical calli (Fig. 39); scales in a row on the elytral intervals erect, much longer than the width of each interval (Fig. 39); male metaventrite more strongly prominent ventrally along the apico-lateral margin of the metaventral receptacle; male ventrite I with no prominence; apical projection of the penis truncate at the apex (Figs 91, 101, 111, 114, 117, 120, and 123); basal part of the endophallus with a pair of weakly falcate sclerites (Figs 90, 100); female sternite VIII with apically divergent arms (Figs 97, 107); bursa copulatrix usually without minute coniform spicules (Figs 95, 105).

Male.

LB: 2.40-2.71 (mean, 2.50). LR: 1.04-1.18 (mean, 1.12). WP: 0.94-1.10 (mean, 1.00). LP: 0.85-0.95 (mean, 0.90). WE: 1.61-1.91 (mean, 1.69). LE: 1.64-1.83 (mean, 1.69). N = 11 for all measurements. Habitus as shown in Figs 5-6.

Vestiture. Clavate scales long and erect on head, basal 2/3 of rostrum, and pronotum. Hair-like scales long and semierect on apical 1/3 of rostrum. Scales on elytral intervals (Fig. 39) erect, long, 1.3-1.5 × as long as interval width. Clavate scales on tibiae erect.

Rostrum (Figs 30-31) slender, 1.15-1.27 × as long as pronotum, sides slightly widened in apical part, which is 1.16 × as wide as basal part. Antennae (Fig. 31) with length ratio of funicular segments I: II: III: IV: V: VI = 1.86: 1.50: 1.21: 1.00: 1.00: 0.93 and width ratio = 1.60: 1.00: 1.13: 1.20: 1.33: 1.47.

Pronotum (Fig. 38) 1.06-1.19 × as wide as long, 0.50-0.56 × as long as and 0.56-0.65 × as wide as elytra; subapical constriction strong; sides subparallel in basal 2/3, then strongly convergent toward apex.

Elytra 0.96-1.04 × as long as wide, 1.79 –1.98× as long as and 1.54 –1.79× as wide as pronotum, straightly convergent toward subapical calli; humeral calli strongly prominent; subapical calli moderately prominent.

Underside. Metaventrite moderately prominent ventrally along apico-lateral margin of metaventral receptacle. Venter coarsely and very densely punctured; ventrite I weakly flattened on disc, lacking prominence; ventrite V with more or less deeper median concavity; length ratio of ventrites I: II: III: IV: V = 3.56: 2.67: 1.00: 1.00: 2.56 and width ratio = 1.90: 1.76: 1.30: 1.20: 1.00.

Genitalia. Tegmen (Figs 93, 103) with apodeme slightly widened toward apex. Penis (Figs 90-92, 100-102, 110-124) with sides more or less weakly widened toward apical 1/5, then strongly convergent apically; apical projection truncate at apex. Basal part of endophallus (Figs 90, 100) with pair of weakly falcate sclerites.

Otherwise as in Scleropteroides hypocrita .

Female.

LB: 2.34-2.92 (mean, 2.68). LR: 1.06-1.36 (mean, 1.30). WP: 0.95-1.14 (mean, 1.09). LP: 0.88-1.04 (mean, 0.96). WE: 1.63-1.97 (mean, 1.82). LE: 1.62-2.03 (mean, 1.83). N = 16 for all measurements.

Rostrum (Figs 32-33) slightly more slender, 1.15-1.40 × as long as pronotum.

Pronotum 1.02-1.18 × as wide as long.

Elytra 0.98-1.05 × as long as wide.

Underside. Ventrite V simple, lacking median sulcus or concavity.

Terminalia and genitalia. Sternite VIII (Figs 97, 107) with arms slender and apically divergent. Bursa copulatrix (Figs 95, 105) usually simple, but sometimes with dense minute coniform spicules in posterior part. Spermatheca (Figs 99, 109, 126, 128, 130, 132) with collum more strongly convex; insertions of duct and gland slightly more distant from each other.

Otherwise showing almost the same sexual dimorphism as in Scleropteroides hypocrita .

Material examined.

CHINA: Hunan. 1 male, Pingjiang, Mt. Mupushan, 1600 m, 1-12-VIII-2003, Li et al. (NIAES). Fujian. 2 males and 2 females, Jianyang, 27°20'N, 118°06'E, 18-IV-1965 (IZCAS, IOZ(E)896779, 896780, 896781, and 896786); 1 female, Jianyang, Aotou, Sanbanqiao, 27°35'N, 117°39'E, 18-IV-1965 (IZCAS IOZ(E)896788); 1 female, Jianyang, Aotou, Huangbaixi, 27°35'N, 117°39'E, 7-V-1965 (IZCAS IOZ(E)89679); 1 male, Jianyang, Aotou, Daoshui, 27°35'N, 117°39'E, 13-VI-1965 (IZCAS, IOZ(E)897690). 1 female, Shaowu, Tieyang, 27°10'N, 117°21'E, 15-V-1965 (IZCAS, IOZ(E)896789). 1 male, Wuyishan, Xingcun, Sangang, 752 m, 27°44.804'N, 117°40.600'E, 15-IV-2009, J. Huang (ZAFU). 1 female, Wuyishan, Xingcun, Sangang, 752 m, 27°44.804'N, 117°40.600'E, 15-IV-2009, S. Zhang (ZAFU). 1 male, Wuyishan, Xingcun, Qili, 899-912 m, 27°43.302'-27°43.042'N, 117°39.632'-117°39.334'E, 20-IV-2009, J. Tan (ZAFU). 1 female, Wuyishan, Xingcun, Qili, 899-912 m, 27°43.302'-27°43.042'N, 117°39.632'-117°39.334'E, 20-IV-2009, J. Huang (ZAFU). Chongqing. 1 female, Nanchuan, Yixiantian, 700 m, 29.05194°N, 107.12001°E, 12-VI-2010, R. Nie (IZCAS IOZ(E)1803625). TAIWAN. 1 male, Nantou, Sungkan–Meifeng, 25-26-V-1972, M. Sakai (EUMJ). 1 male and 1 female, Nantou, Nanshanchi, 20-23-III-1995, H. Kojima and M. Suehiro (NIAES). 1 male, Mt. Guandaoshan, 16-V-1986, I. Matoba (NIAES). 1 male, Taoyuan, Mt. Daguanshan, 4-IV-1991, H. Kojima (NIAES). KOREA: Gangwondo. 1 female, Chuncheongun, Dongmyeon, Gamjeongri, 21-V-1992, K. Morimoto (ELKU). Kyeongsangnamdo. 1 female, Mt. Jirisan, Samjeongri, 6-VI-1991, J. D. Bae (ELKU). Jeollabukdo. 1 male and 1 female, Namwongun, Nowondan, 5-VI-1991, J. D. Bae (ELKU). 1 female, Namwongun, Deongdongri, 19-VI-1994, H. Kojima (ELKU). JAPAN: Nansei Islands. YAKUSHIMA I. Nakama: 1 male, 1-IV-1985, A. Yoshida (NIAES); 1 male and 2 females, 25-III-1991, H. Kojima (ELKU); 4 males and 6 females, 30-III-2005, Y. Kubota (NIAES). AMAMI-OSHIMA I. 1 male, Sutaru-touge Pass, 23-III-1954, T. Mohri (EUMJ). Nishinakama: 1 female, 25-III-1954, T. Edashige (EUMJ); 1 female, 31-III-1968, M. Tomokuni (EUMJ); 1 male, 22-III-1990, T. Ueno (NIAES). Hatsuno: 1 male and 1 female, 24-III-1965, S. Fukuda (SM); 1 female, 12-IV-1971, M. Sakai (EUMJ); 1 female, 11-V-1976, J. Okuma (SM). 1 male, Daikuma, 10-IV-1971, M. Sakai (EUMJ). 1 female, Shinmura, 11-IV-1971, M. Sakai (EUMJ). Mt. Yuwandake: 1 male, 19-IV-1971, M. Sakai (EUMJ); 25 males and 18 females, 25-28-III-2003, H. Yoshitake, on Rubus croceacanthus (NIAES). 9 males and 8 females, Chuo-rindou, 18-III-1991, H. Kojima (ELKU). 2 males, Nangawa-rindou, 20-III-1991, H. Kojima (ELKU); 1 male and 2 females, 22-III-1991, H. Kojima (ELKU). 2 males and 5 females, Mt. Akatsuchiyama, 21-III-1991, H. Kojima (ELKU). UKEJIMA I. 1 male, 22-III-2004, K. Takahashi (NIAES). OKINAWAJIMA I. 1 female, Yona, 10-IV-1975, S. Imasaka (NIAES). 1 male, Oku, 15-18-V-1978, T. Tsutsumi (ELKU). 2 males and 1 female, Mt. Yonahadake, 16-IV-1991, H. Kojima (ELKU).

Distribution.

China (Chongqing and Fujian - new record, and Taiwan), Korea (Central and South - new record), Japan (Nansei Islands: Yakushima, Amami-Oshima, and Okinawajima Islands; Fig. 134).

Biological note.

A number of adults were collected from Rubus croceacanthus H. Lév. growing along the edge of an evergreen broad-leaved forest at the foot of Mt. Yuwandake, Amami-Oshima Island.

Comment.

In the study, we could not examine the holotype of Rhytidosomus insularis Voss, which should be preserved in ELKU, but K. Morimoto (pers. comm., 2005) had examined it and confirmed its taxonomic identity. Also, our examination of a long series of Scleropteroides specimens from the type locality, Amami-Oshima Island, revealed that only one species of this genus occurs on the island.