Aphanerostethus japonicus Lewis & Kojima, 2024

Lewis, Jake H., Kojima, Hiroaki, Suenaga, Miyuki, Petsopoulos, Dimitrios, Fujisawa, Yusuke, Truong, Xuan Lam & Warren, Dan L., 2024, The era of cybertaxonomy: X-ray microtomography reveals cryptic diversity and concealed cuticular sculpture in Aphanerostethus Voss, 1957 (Coleoptera, Curculionidae), ZooKeys 1217, pp. 1-45 : 1-45

Aphanerostethus japonicus Lewis & Kojima sp. nov.

Figs 3 , 6 C – F , 11 C , 13 F , 15 I, J , 16 C, D , 18 B

Specimens examined.

Holotype: Japan: Miyazaki Prefecture: • Gokase-chou, Shiraiwa-yama , 6. V. 2009, Y. Tsutsumiuchi, male deposited in KUM, JHLHY_DAR_052 . Paratypes: Japan: Ehime Prefecture: • Odamiyama, 2. IV. 1986, E. Yamamoto, (1, KUM), JHL_SYN_197 ; Kagawa Prefecture: • Shionoe-chou, Ootaki-yama , 11. VII. 1992, K. Kume, (1, KUM), JHLHY_DAR_053 ; Miyazaki Prefecture: • Gokase-chou, Shiraiwa-yama , 6. V. 2009, Y. Tsutsumiuchi, (3, KUM; 1, OIST), JHLHY_DAR_048 – JHLHY_DAR_051 ; • Gokase, Mt. Mokouzaka , 17. VI. 2017, R. Ito, (4, KUM), JHLHY_DAR_059 (EGP 0160 E 04), JHL_SYN_194 – JHL_SYN_196 ; • Mt. Goyodake, Hinokage , 15. VII. 2018, R. Ito, (1, KUM), JHL_SYN_199 ; Oita Prefecture: • Saiki-shi, Fujigawachi-keikoku , 10. IX. 2017, R. Ito, (2, KUM), JHLHY_DAR_054 , JHLHY_DAR_055 ; • Saiki-shi, Fujigawachi-keikoku , 18. V. 2018, R. Ito, (3, KUM), JHLHY_DAR_056 – JHLHY_DAR_058 , EGP 0160 E 05 ; Okinawa Prefecture: • Okinawa Island, Kunigami, Yona Field (26.73894°N, 128.23720°E), 10–24. VI. 2016, L. Iha, T. Kinjo, (1, OIST), OKENT 0062435 ; • Okinawa Island, Kunigami, Yona Field (26.73894°N, 128.23720°E), 5–19. II. 2016, L. Iha, T. Kinjo, (1, OIST), OKENT 0055232 (EGP 0160 B 12) ; • Okinawa Island, Kunigami, Yona Field (26.73894°N, 128.23720°E), 22. VII. – 5. VIII. 2016, T. Kinjo, K. Uekama, (1, OIST), OKENT 0055516 (EGP 0160 B 11) ; • Okinawa Island, Kunigami, Yona Field (26.73894°N, 128.23720°E), 27. XI. – 11. XII. 2015, Y. Tamaki, S. Iriyama, T. Yoshida, (1, OIST), OKENT 0055168 ; Tokushima Prefecture: • Mima-gun, Tsurugi-chou, Ichiu , 33°53'N, 134°4'E, 31. VII. 2011, K. Kume, (4, KUM; 1, OIST), JHLHY_DAR_037 – JHLHY_DAR_041 ; • Mt. Tomaru, Tsurugi-chou , 27. VII. 2014, K. Kanno, (1, KUM), JHL_SYN_198 ; • Nishiiyayama-son , 33°58'N, 133°4'E, 4. VIII. 2021, K. Kume, (1, KUM), JHLHY_DAR_042 ; • Miyoshi-shi, Mikamo-chou, Furonto , 22. VII. 2012, K. Kume, (4, KUM; 1, OIST), JHLHY_DAR_043 – JHLHY_DAR_047 (EGP 0160 F 03) .

Diagnosis.

Body length 1.4–1.7 mm. Cuticle coated in crusty dark, sandy gray, and white scales in weakly defined pattern. Funicle with six articles. Procoxae contiguous. Eyes not dimorphic (separated in both sexes). Only odd-numbered elytral intervals with erect scales. Erect elytral scales evenly distributed, not concentrated in bundle. Scutellum distinct. Femora each with low, obtuse tooth ventrally. Prosternal cavity very weakly defined and without steep lateral ridges. Metaventrite flattened between meta- and mesocoxae, without a distinct elevated transverse ridge. Metatibial uncus simple in both sexes. Aedeagus rounded in lateral half (Fig. 15 I, J ). Internal sac with basal protruding structure (Fig. 15 I, – J ).

Distribution.

This species is currently only known from Japan, north from Tokushima Prefecture and Kagawa Prefecture, and in the Ryukyu Islands from Okinawa Prefecture (Yambaru National Park).

Etymology.

The specific name japonicus is a Latin adjective in reference to the country of collection. We also suggest the Japanese common name ニッポンダルマクチカクシゾウムシ [Nippon-daruma-kuchi-kakushi-zômushi], which translates in English to “ Japanese daruma cryptorhynchine weevil ”.

Variation.

Specimens of A. japonicus from Okinawa Island are noticeably slenderer than those collected on the mainland, but are otherwise indistinguishable and do not possess any structural characters that would support treating these as different species.

Comments.

The exact phylogenetic relationship of A. japonicus (along with A. nudus and A. armatus ) to typical Aphanerostethus (i. e., those possessing a prominent prosternal canal and ridge between the meso- and metacoxae) remains uncertain given that the molecular data presented here does not clearly suggest whether they represent a lineage nested within or sister to typical Aphanerostethus (see Fig. 3 ). However, the fact that A. nudus possesses dimorphic metatibial uncus, a character which occurs sparsely in weevils, is significant and further supports the association of typical Aphanerostethus and the A. nudus group.

Like A. distinctus (see Comments under A. distinctus ), this species was only collected from one site (Yona, Yambaru National Park) on Okinawa Island despite several years of malaise trapping at twenty-four sites across the island suggesting that it is also sensitive to anthropogenic disturbance.

Figures

Figure 3. Maximum likelihood tree of Aphanerostethus species based on an 872 base-pair long concatenated DNA matrix (CO 1, Cytb, 16 S) with gene-wise partition modelling (CO 1 / Cytb: GTR + F + I + G 4; 16 S: GTR + F + G 4) constructed in IQ-TREE v. 1.6. 12. Branch support values represent standard nonparametric bootstraps (1000 replicates) and posterior probabilities. The symbol “ – ” indicates a posterior probability less than 50 (i. e., collapsed nodes in the Bayesian Inference tree). EGP codes represent DNA extraction codes and serve also as unique specimen identifiers. Associated Aphanerostethus weevil figures on the right of the tree are not to scale. Note that, except for A. distinctus and A. taiwanus (see Comments under the A. taiwanus species profile), the monophyly of all Aphanerostethus species is strongly supported (BS: 100, PP: 1).

Figure 6. X-ray microtomography generated 3 D models of Aphanerostethus pronota with scales removed, revealing otherwise hidden differences in underlying puncture morphology A, B Aphanerostethus incurvatus sp. nov. (JHLHY _ DAR _ 095, 104) C – F Aphanerostethus japonicus sp. nov. (OKENT 0055232, JHLHY _ DAR _ 051, 052, 041).

Figure 11. X-ray microtomography generated 3 D models of Aphanerostethus with the right elytron removed, revealing differences in the length, width, and venation of the hindwing (as shown here, the hindwing is affixed to the inner surface of the elytron in most specimens). A lateral view of the full body is shown below each close-up for reference. The red, blue, and yellow arrows indicate the base, midpoint, and apex of the hindwing, respectively A Aphanerostethus bifidus sp. nov. (JHLHY _ DAR _ 092) B A. decoratus sp. nov. (JHLHY _ DAR _ 079) C A. japonicus sp. nov. (JHLHY _ DAR _ 041) D A. magnus sp. nov. (JHLHY _ DAR _ 032).

Figure 13. X-ray microtomography generated 3 D models of Aphanerostethus A, B A. armatus sp. nov. (JHLHY _ DAR _ 078) shallow prosternal canal C, D A. magnus sp. nov. (JHLHY _ DAR _ 029) deep prosternal canal E A. armatus (JHLHY _ DAR _ 078) fore-femur showing elongate, thorn-like ventral tooth F A. japonicus sp. nov. (JHLHY _ DAR _ 051) fore-femur showing blunt, obtuse ventral tooth.

Figure 15. Aedeagi of Aphanerostethus species A, B A. bifidus sp. nov. (JHLHY _ DAR _ 102) C, D A. distinctus (Morimoto & Miyakawa, 1985) (OKENT 87658) E, F A. falcatus sp. nov. (JHLHY _ DAR _ 099) G, H A. incurvatus sp. nov. (JHLHY _ DAR _ 100) I, J A. japonicus sp. nov. (JHLHY _ DAR _ 052) K, L A. magnus sp. nov. (JHLHY _ DAR _ 022) M, N A. morimotoi sp. nov. (JHLHY _ DAR _ 113) O, P A. nudus sp. nov. (JHLHY _ DAR _ 012) Q, R A. spinosus sp. nov. (JHLHY _ DAR _ 077) S, T A. taiwanus sp. nov. (JHLHY _ DAR _ 016) U, V A. vannideki Voss, 1957 (JHLHY _ DAR _ 082).

Figure 16. Lateral and dorsal photographs of Aphanerostethus species A, B A. darlingi sp. nov. (JHLHY _ DAR _ 126) C, D A. japonicus sp. nov. (OKENT 0055168). Scale bars: 0.5 mm.

Figure 18 A Prominent ridge between meso- and metacoxae (Aphanerostethus distinctus (Morimoto & Miyakawa, 1985), OKENT 0087604) B No prominent ridge between meso- and metacoxae (A. japonicus sp. nov., OKENT 0055168).