Acicnemis postica Hubenthal, 1919

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 postica Hubenthal, 1919

Figs 1 , 6 M 1–6 , 2 , 24

Acicnemis cruciata Kleine, 1924 , syn. nov.

Type material examined

( Japan: 31; Taiwan: 5; Total: 36). Lectotype (designated here): Taiwan • “ Formosa Is. ”, “ Coll. Pape ”, SDEI Müncheberg Col – 18570 (1, SDEI), bears red label reading “ Syntypus ” and a new, red lectotype label reading “ LECTOTYPE / Acicnemis postica / Hubenthal, 1919 / Det. Lewis & Kojima, 2025 ” . Paralectotypes. Taiwan • Fuhosho , “ IX- 7–09 ”, H. Sauter, SDEI Müncheberg Col – 18571 (1, SDEI), bears red label reading “ Syntypus ” and a new, yellow paralectotype label ; • Kankau ( Koshun ), VI. 1912, H. Sauter, SDEI Müncheberg Col – 18572 (1, SDEI), bears red label reading “ Syntypus ” and a new, yellow paralectotype label .

Other type material.

• Kosempo, “ VII – 19 ”, H. Sauter, Acicnemis cruciata holotype (1, SDEI), SDEI Coleoptera # 303422, SDEI Müncheberg Col – 18568.

Non-type material.

Taiwan • Taoyuan Hsein, Paling , 24. V. 1977, H. Fujita (1, KUM), JHL_ACITAI_057 ; • Wenchuan Hsein, Lushan , 4. VII. 1978, T. Mikage (1, KUM), JHL_ACITAI_058 ; • Ping Tung Hsein, Kenting , 2. IV. 1965, S. Ueno (1, KUM), JHL_ACITAI_060 ; • Kenting , 31. III. 1970, Y. Miyake (2 dissected males, KUM), JHL_ACITAI_082 , JHL_SYN_179 ; • Chihpen Wenchuan , Taitung Hsien, 7. VI. 1980, H. Makihara (1, KUM), JHL_AREV_735 ; • Jiuyuehtan , 31. V. 1978, K. Kusama (1, KUM), JHL_AREV_736 ; • Taidong, Lijia road , 22.8062°N, 121.0310°E, 19. VIII. 2013, V. Grebennikov (1, CNCI), CNCCOLVG 00006901 (BOLD accession number: MEBLA 191-14) ; Japan: Kagoshima Prefecture: • Shinokawa, Setouchi-cho, Amami Oshima , 10. VII. 2008, K. Ozaki (1, CMIC), CBM ZI 136615 ; • Nakanoshima Island , 1–2. V. 1975, H. Irie (1, KUM), JHL_AREV_750 ; • Nagata , Yakushima Island, 17. V. 1960, J. Nagao (1, KUM), JHL_AREV_754 ; • Mt. Kindake , Nakano Is., 7–9. VI. 2019, S. Imada, (1, KUM), JHL_AREV_780 ; Okinawa Prefecture: • Ishigaki Island, Mt. Omoto , 18–22. VI. 1991, K. Morimoto (1, KUM), JHL_ACITAI_055 ; • Mt. Omoto , 21. V. 1977, H. Irie (1, KUM), JHL_AREV_755 ; • Mt. Omoto , 18–21. IV. 1975, H. Irie (1 dissected male, KUM), JHL_ACITAI_062 ; • Ushikumori , Iriomote Island, 7. X. 1963, K. Morimoto (1, KUM), JHL_AREV_756 ; • Yonaguni Island, Urabu-dake , 25–26. VI. 1974, T. Mikage (6, KUM), JHL_ACITAI_056 , JHL_AREV_751 – JHL_AREV_753 ; • Okinawa Island, Hiji , 9. VII. 1974, T. Mikage (2, KUM), JHL_ACITAI_059 ; • Fusato , Okinawa Island, 5. VI. 1970 (1, KUM), JHL_AREV_762 ; • Omotodake , Ishigaki Island, 8. VII. 1968, M. Takagi (1, KUM), JHL_AREV_761 ; • Funaura , Iriomote Island, 2. X. 1978 (2, RUMC), JHL_AREV_709 , JHL_AREV_710 ; • Banna , Ishigaki Island, 14. III. 1964, S. Azuma (1, RUMC), JHL_AREV_712 ; • Haneji , Okinawa Island, 10. VIII. 1979, T. Kohama (1, RUMC), JHL_AREV_711 ; • Mt. Inbi-take , Yonaguni Island, 2. VI. 2021, S. Imada (1, KUM), JHL_AREV_723 ; • Kuburadake , Yonaguni Island, 15. VI. 2001, L. Hirano (1, KUM), JHL_AREV_725 ; • Shirahama , Iriomote Island, 31. VIII – 5. IX. 1969, H. Makihara (9, KUM), JHL_AREV_726 – JHL_AREV_734 ; • Shirahama , Iriomote Island, 4. X. 1963, S. Ueno (1, KUM), JHL_AREV_737 ; • upper Nakara , Iriomote Island, 12. III. 1964, Y. Miyatake (1, KUM), JHL_AREV_738 ; • Komi , Iriomote Island, 12. VII. 1963, Y. Miyatake (1, KUM), JHL_AREV_739 ; • Sonai , Yonaguni Island, 25–29. VIII. 1969, H. Makihara (10, KUM), JHL_AREV_740 – JHL_AREV_749 ; • Okinawa Island (1, OIST), JHL_AREV_983 (GenBank accession number: PV 255638 ) ; • Tancha , Okinawa Island, 18. V. 2024, J. H. Lewis, sweeping vegetation (1, OIST), JHL_AREV_994 .

Diagnosis.

Body length 3.2–5.2 mm. Covered in orange, white, dark and pale gray scales. Elytra with inner five or six intervals black and gray; outer intervals with pale brown to orange scales; with V-shaped band of white scales along middle three or four intervals in center of elytra. Pronotum lacking impunctate longitudinal midline (present in A. koguma ). Scutellum small and covered in erect, hair-like yellow scales. Elytra with erect scales only on odd intervals. Sclerolepidia distinct and protruding. Third tarsomeres emarginate. Metatibia evenly curved, not sinuate as in most other species. Pedon with lateral edges approx. parallel in dorsal view, but converging evenly into a blunt, rounded point. Internal sac not visible inside aedeagus, but protruding and with two sclerotized cylinder-shaped structures posteriorly near the base (Fig. 6 M 1 – 2 ).

Distribution.

This species occurs commonly throughout southern Japan (Ryukyu Islands) and Taiwan.

Remarks.

Examination of the A. cruciata Kleine, 1924 syn. nov. holotype ( SDEI Coleoptera # 303422) revealed that this is a junior synonym of A. postica as it possesses all of the key characteristics that define this distinctive species (same scale pattern, evenly curved metatibiae, small, scaled scutellum). We designate one of the Hubenthal A. postica syntypes ( SDEI Müncheberg Col – 18570) as a lectotype to fix the identity of this species.

Figures

Figure 1. Maximum likelihood tree of twelve Acicnemis species based on a 300 base-pair long CO 1 gene fragment constructed in IQ-TREE v. 1.6. 12 using a GTR + F + I + G 4 model. Branch support values represent standard nonparametric bootstraps (1000 replicates). Bootstrap values less than 75 are not displayed on the tree. The codes MEBLA 191-14, VVGPL 2845-15, and OWEVG 891-15 are BOLD Systems accession numbers, whereas all other codes are GenBank accession numbers. Associated Acicnemis weevil figures on the right of the tree are approximately to scale.

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 24. Acicnemis postica Hubenthal, 1919 (JHL _ AREV _ 780). A. Lateral; B. Dorsal. Scale bar: 1 mm.