Acicnemis dividicincta dividicincta Morimoto & Miyakawa, 1995

Lewis, Jake H., Kojima, Hiroaki & Campbell, Erin O., 2025, A Japan-focused review of East Asian Acicnemis Fairmaire, 1849 (Coleoptera, Curculionidae) reveals cryptic diversity in a well-studied region, ZooKeys 1259, pp. 103-167 : 103-167

Acicnemis dividicincta dividicincta Morimoto & Miyakawa, 1995

Figs 6 D 1–6 , 2 , 13

Acicnemis yakushimana Morimoto & Miyakawa, 1995 , syn. nov.

Type material examined

(Japan: 34). Holotype. Japan: Okayama Prefecture: • Mt. Gagyuzan , Takahashi City, 19–20. V. 1975, H. Irie, bears red label reading “ (HOLOTYPE) Acicnemis dividicincta Morimoto et. Miyakawa, 1994 ”, JHL_SYN_120 , ELKU, ELKU 2957 . Paratypes. Fukuoka Prefecture: • Mt. Hiko , 5. IX. 1988, K. Morimoto (1, KUM), JHL_SYN_118 ; Kochi Prefecture: • Mt. Tebako , 7–10. VIII. 1957, K. Morimoto (2, KUM), JHL_SYN_114 , JHL_SYN_115 ; Nagasaki Prefecture: • Unzen , 18. VII. 1946, M. Moritsu & Y. Kurosawa (3, KUM), JHL_SYN_102 (dissected male), JHL_SYN_113 , JHL_SYN_119 ; Okayama Prefecture: • Mt. Gagyuzan , Takahashi City, 19–20. V. 1975, H. Irie (3, KUM), JHL_SYN_111 , JHL_SYN_112 , JHL_DNA_142 (dissected male) ; Wakayama Prefecture: • Mt. Ootoh , 7. VIII. 1980, I. Matoba (1, KUM), JHL_SYN_116 .

Other type material.

Kagoshima Prefecture: • Miyanoura, Yakushima Island , 26. VII. 1974, T. Mikage, bears red label reading “ ( HOLOTYPE) Acicnemis yakushimana Morimoto et. Miyakawa, 1994 ”, JHL_SYN_180 (1, ELKU), A. yakushimana holotype specimen, ELKU 2959 ; • Miyanoura, Yakushima Island , 26–29. VII. 1974, T. Mikage (13, KUM), JHL _SYN_122 – JHL _SYN_124 , JHL _SYN_127 – JHL _SYN_130 , JHL _SYN_132 , JHL _SYN_133 , JHL _SYN_138 , JHL _SYN_139 , JHL _DNA_141 (dissected male) ; • Shiratani, Yakushima Island , 24–26. VII. 1974, T. Mikage (2, KUM), JHL _SYN_121 , JHL _SYN_131 ; • Mt. Tachudake, Yakushima Island , 20. VII. 1971, H. Irie (4, KUM), JHL _SYN_125 , JHL _SYN_126 , JHL _SYN_134 , JHL _SYN_135 ; • Ambo – Kosugidani, Yakushima Island , 29. VII. 1929, Hiroshi Hori (2, KUM), JHL _SYN_136 , JHL _SYN_137 ; • Shiratani-rindo, Yakushima Island , 20. VII. 1976, M. Kaneda (1, KUM), JHL _AREV_663 .

Non-type material.

Ehime Prefecture: • Omogo, Iyu , 19. VIII. 1969, T. Nakane, (1, HUM), JHL _AREV_772 ; • Tokyo Metropolis: Hachijo-jima, Mitsune , VI. 2001, T. Kinoshita (1 dissected male, KPMNH), JHL _AREV_936 ; • Hachijo-jima, Noboryou-toge , 9. VI. 1996, I. Hirai (1, KUM), JHL _AREV_938 .

Diagnosis.

Body length 4.2–7.0 mm. Covered in black and dark gray scales, with two V-shaped, transverse white and black bands across middle of elytra. Pronotum with weakly patterned gray, black and faint yellow scales. Scutellum covered loosely in yellow scales (denuded in many specimens). Only odd elytral intervals with erect scales across elytral disk (some erect scales on 2 nd interval in apical fourth of elytra). Sclerolepidia distinct and protruding. Third tarsomeres distinctly emarginate. Pedon with lateral edges approx. parallel in dorsal view, but converging evenly into a moderately acute point. Internal sac not visible inside aedeagus, but with a non-hooked protruding structure (unmodified in posterior 1 / 2, with roughened in anterior 1 / 2) that is clearly longer than pedon (Fig. 6 D 1 – 2 ).

Distribution.

This subspecies occurs in mainland Japan (central Japan south to Yakushima Island) and adjunctly on Hachijo Island ( Tokyo Metropolis).

Remarks.

Acicnemis yakushimana was distinguished from A. dividicincta by Morimoto and Miyakawa (1995) on the basis of purported differences in the relative proportions of the funicular antennomeres and minor differences in color. Furthermore, A. yakushimana also reportedly possessed a sclerite in the internal sac at the gonopore. After dissecting several specimens of each species across their geographic range, we did not observe any differences in genital morphology between A. yakushimana and A. dividicincta . Furthermore, no observable differences in antennal funicle proportions were observed. As such, we hereby treat A. yakushimana syn. nov. as a junior subjective synonym of A. dividicincta .

Figures

Figure 2. Diagnostic morphological characters in Acicnemis. A. A. azumai Morimoto & Miyakawa, 1995 (JHL _ ACITAI _ 081) showing lack of prominent posterior prosternal projections; B. A. laeta Hubenthal, 1919 (JHL _ AREV _ 533) showing prominent prosternal projections; C. A. kiotoensis Nakane, 1963 (JHL _ AREV _ 982) showing antenna with the second funicular antennomere longer than antennomeres 3 + 4; D. A. koguma Lewis & Kojima, sp. nov. (JHL _ SYN _ 141) showing antenna with the second funicular antennomere shorter than antennomeres 3 + 4; E. A. luteomaculata Morimoto & Miyakawa, 1995 (JHL _ AREV _ 189) showing truncate third tarsomere; F. A. ryukyuana Lewis, 2023 (JHL _ ACI _ 011) showing weakly emarginate third tarsomere; G. A. maculaalba Roelofs, 1875 (JHL _ AREV _ 577) showing strongly emarginate third tarsomere.

Figure 6. Aedeagi of Acicnemis. A 1–2. A. albofasciata (Ter-Minasian 1953); B 1–2. A. azumai Morimoto & Miyakawa, 1995; C 1–2), A. cryptica Lewis & Kojima, sp. nov.; D 1–2. A. dividicincta Morimoto & Miyakawa, 1995; E 1–2. A. exilis Morimoto & Miyakawa, 1995; F 1–2. A. kiotoensis Nakane, 1963; G 1–2. A. laeta Hubenthal, 1919; H 1–2. A. luteomaculata Morimoto & Miyakawa, 1995; I 1–2. A. maculaalba Roelofs, 1875; J 1–2. A. nobilis Hubenthal, 1919; K 1–2. A. nohirai Morimoto & Miyakawa, 1995; L 1–2. A. palliata Pascoe, 1872; M 1–2. A. postica Hubenthal, 1919; N 1–2. A. ryukyuana Lewis, 2023; O 1–2. A. sauteri Hubenthal, 1919; P 1–2. A. shibatai Voss, 1971; Q 1–2. A. shigematsui Morimoto & Miyakawa, 1995; R 1–2. Acicnemis sp. 1; S 1–2. A. squamata Lewis & Kojima, sp. nov.; T 1–2. A. suturalis Roelofs, 1875.

Figure 13. Acicnemis dividicincta dividicincta Morimoto & Miyakawa, 1995 (JHL _ AREV _ 772). A. Lateral; B. Dorsal. Scale bar: 1 mm.