Aphanerostethus magnus Lewis & Kojima sp. nov.

Figs 2 A – D, 3, 7 A – C, 11 D, 13 C, D, 15 K, L, 19 C, D

Specimens examined.

Holotype: Japan: Kagoshima Prefecture: • Nakanoshima Is., 1–2. V. 1975, H. Irie, male deposited in KUM, JHLHY_DAR_023 . Paratypes: Japan: Kagoshima Prefecture: • Nakanoshima Is., 1–2. V. 1975, H. Irie, (4, KUM; 1, OIST), JHLHY_DAR_022, JHLHY_DAR_024 – JHLHY_DAR_026, JHLHY_DAR_076 ; • same locality, 7. VII. 1974, J. Okuma, (2, KUM), JHLHY_DAR_027, JHLHY_DAR_028; • same locality, 5. VIII. 1989, T. Ueno, (2, KUM; 1, OIST), JHLHY_DAR_029 – JHLHY_DAR_031; • same locality, 28. V. 1962, M. Sato, (1, KUM), JHLHY_DAR_034; • Nakanoshima, Sato, 7. VII. 1974, J. Okuma, (1, KUM), JHLHY_DAR_032 ; • Nakanoshima, Satsuda, 14. VII. 1982, Y. Takai, (1, KUM), JHLHY_DAR_033 ; • Nakanoshima, 29. IV. 1987, S. Nomura, (1, KUM), JHLHY_DAR_075 ; • Nakanoshima, 14. VII. 1986, H. Fujita, (1, HUM), JHLHY_DAR_141 ; • Nakanoshima, 6. VI. 1953, (1, HUM), JHLHY_DAR_142 ; • Nakanoshima, 21. VII. 1969, M. Sakai, (2, KUM), JHLHY_DAR_139, JHLHY_DAR_140 ; • Nakanoshima, entrance of Mt. Otake-tozandoro, 2. X. 2015, H. Kojima, (1, TUA), JHLHY_DAR_108, EGP 0160 C 08 ; • Kuchinoshima, Seranma, 5. V. 2013, H. Kojima, (1, TUA), JHLHY_DAR_107, EGP 0160 C 07 ; Kouchi Prefecture: • Okinoshima Is., 31. VII. 1953, K. Morimoto, (1, KUM), JHLHY_DAR_035 ; Taiwan: Kaohsiung City: • Liouguei District, Zhong-Xing-Long Li, near Mt. Taiyuanshan, 19. X. 2015, H. Yoshitake, (2, NMNST), JHLHY_DAR_065 (EGP 0160 E 09), JHLHY_DAR_066 (EGP 0160 E 10) .

Diagnosis.

Body length 2.6–3.0 mm. Cuticle covered in dark to pale brown scales, with dark, V-shaped band across anterior part of elytra. Procoxae contiguous. Funicle with six articles. Second and odd-numbered elytral intervals with erect scales. Erect elytral scales variably concentrated in bundle on first elytral interval at apex of V-shaped band. Scutellum prominent and bulging. Elytral intervals moderately convex. Femora all with ventral tooth along ventral edge at midpoint. Prosternal cavity prominent and with steep lateral ridges. Metaventrite with a distinct elevated transverse ridge separating the meta- and mesocoxae. Metatibial uncus C-shaped in male (Fig. 2 A – D). Aedeagus tapering in lateral half and weakly subquadrate at apex (Fig. 15 K, L). Internal sac lacking prominent basal protruding structure (Fig. 15 K, L).

Distribution.

This species is known from Nakanoshima Is. (Kagoshima Prefecture) and Okinoshima Is. (Kouchi Prefecture), Japan, as well as Zhong-Xing-Long Li (Liouguei District), Taiwan.

Etymology.

The specific name magnus is a Latin adjective in reference to the distinctly large body size and elongate aedeagus of this species. We suggest the Japanese common name オオダルマクチカクシゾウムシ [Oo-daruma-kuchi-kakushi-zômushi], which translates in English to “ Big daruma cryptorhynchine weevil ”.

Comments.

This species is closely allied with A. bifidus, a phylogenetic hypothesis which is also strongly supported by our molecular phylogenetic analysis (BS: 95, PP: 1). Both A. bifidus and A. magnus exhibit the same distinctive brown scaling pattern, similarity in metatibial uncus morphology, and general appearance. Aphanerostethus magnus is present in the Osumi and Tokara Islands and Taiwan, but apparently absent from the more southern Nansei Island groups such as the Amami Islands, the Okinawa Islands, and the Sakishima Islands. This peculiar distributional pattern occurs in a number of other weevil species, such as Acicnemis sauteri Hubenthal, 1917, Dendropemon japonicus (Morimoto, 1979), Orychodes planicollis (Walker, 1859), and Stiboderes impressus (Jordan, 1912) (Kojima and Morimoto 2004), and possibly is explained by climatic and floristic differences between these regions as there are few large mountains in the Nansei Islands south of the Tokara Islands that could harbor high-altitude or more northerly distributed species.