Miridiba (Miridiba) huesiotoi Li & Yang

Li, Chun-Lin, Yang, Ping-Shih & Wang, Chuan-Chan, 2015, A review of the genus Miridiba Reitter (Coleoptera: Scarabaeidae: Melolonthinae) of Taiwan, Zootaxa 3955 (4), pp. 521-536 : 524-527

Miridiba (Miridiba) huesiotoi Li & Yang , new species

Figs. 2 , 8 , 14, 20, 27, 28

Male ( Fig. 2 ). Body length 17.6–20.0 mm; width across humeri 8.3–9.6 mm. Color dark reddish brown to rufotestaceous on dorsal surface, venter, and legs; moderately shiny. Antennae reddish brown. Dorsum overall covered with brownish pale setae; setae on head long, robust, and erect; setae on frons intermixed with setae 2–3 times longer; setae on pronotum and elytra shorter than setae on head; pronotal disc with setae 2–3 times longer than diameter of puncture; setae on scutellum and elytra mostly subequal to diameter of puncture with exception of setae on base, which is approximately 2–4 times longer (Fig. 14). Head: Surface densely rugopunctate, punctures large. Clypeus ( Fig. 8 ) with apex moderately bilobed and reflexed, narrowed at base. Clypeofrontal suture clearly defined. Basal carina slightly curved at middle, distinctly raised. Antenna with 9 antennomeres, club subequal to length of antennomeres 2–6 combined. Thorax: Pronotum widest at middle, anterolateral angles slightly protuberant, basolateral angles obtuse, lateral margin coarsely serrate, moderately reflexed; lateral declivities with weak gibbosity behind middle; anterior margin completely beaded, basal margin smooth; setiferous punctures more shallow and smaller than those on clypeus, rarely confluent. Scutellum triangular, basal half of midline slightly raised; punctures identical to those on pronotum. Prosternal process tongue-like, raised apically. Elytra: Discal surface densely rugopunctate; sutural costa gradually broadening apically, widest at apical one-third. Abdomen: Pygidium wider than long; discal surface moderately rugopunctate with setiferous punctures, setae on apical part longer than basal setae. Sternites 1, 2, 5, and 6 with surface densely punctate; sternites 3 and 4 less densely punctate, punctures setiferous, setae short; sternites 5–6 with setae intermixed with 2–8 times longer setae. Legs: Protibia tridentate. Profemora and mesofemora sparsely covered with hair-like, long setae; setae on discal surface of metafemora distinctly shorter; metafemora slender, slightly broadened at middle, not convex ( Fig. 20 ). Metatibia upper spur reaching basal one-third of second tarsomere. Genitalia: Parameres with upper part slightly concave at middle of upper margin (indicated by arrow in Fig. 27 ), distinctly curved downwardly and largely below lower part (indicated by two-headed arrow in Fig. 27 ) when viewed laterally ( Fig. 27 ); parameres moderately widened in dorsal view ( Fig. 28 ).

Female. Body length 19.7–20.8 mm; width across humeri 9.1–10.1mm. Antennal club shorter than in male, subequal to length of antennomeres 3–6 combined. Length of setae on pronotum subequal to diameter of puncture; setae on elytral disc shorter than diameter of puncture, except for setae on base,.

Diagnosis. Miridiba huesiotoi can be separated from the similar species, M. formosana , by the following combination of characters: setae on pronotum, elytra, and scutellum distinctly long in M. formosana ( Figs. 10 , 16) (distinctly short, hardly observable (high magnification required) in M. huesiotoi ( Figs. 8 , 14)); apex of clypeus weakly bilobed in M. formosana ( Fig. 10 ) (moderately bilobed in M. huesiotoi ( Fig. 8 )); anterior angles of pronotum moderately protuberant ( Fig. 10 ) (slightly protuberant in M. huesiotoi ( Fig. 8 )); metafemora broadened anteriorly and posteriorly in M. formosana ( Fig. 22 ) (metafemora slender, slightly broadened at middle in M. huesiotoi ( Fig. 20 )); parameres with upper part strongly curved downwardly above lower part in M. formosana ( Fig. 31 ) (upper part curved downwardly and largely below lower part in M. huesiotoi ( Fig. 32 ).

Type material. The male holotype is pinned and with the following information on the label: Taiwan: Tai Tung Co., Green Island, 4/IV/2004, collr. H.-Y. Lee. The holotype is deposited in NMNS. Paratypes: 5 males and 6 females: 3 males and 1 female with same collecting data as holotype in CCLI; same locality as holotype, 26–27/III/ 1998, C-F. Lee (1 male and 1 female in NMNS; 1 male and 1 female in TFRI; 2 females in CCLI); same locality as holotype, Amei Hill, 4–7/IV/2004, H. Yoshitomi (1 female, CCLI).

Distribution. Southeastern Taiwan (Green Island) ( Fig. 43 ).

Etymology. The specific name refers to the type locality, Green Island, in pronunciation of Taiwanese language.

Chinese name. 火燒島脊頭鰓金龜

Remarks. The type series of the new species was collected in Green Island, which is a small island located approximately 30 km off the southeastern coast of Taiwan ( Fig. 43 ). Further investigation to find out whether there is any population of M. huesiotoi in the main island is needed.

Figures

FIGURE 43. Distribution map of Miridiba species in Taiwan: Miridiba kuraruana (open circle), Miridiba formosana (open triangle), Miridiba taipei (black diamond), Miridiba sinensis (open square), and Miridiba huesiotoi and Miridiba taoi indicated by arrow, respectively.

FIGURES 1 – 6. Dorsal habitus of male Miridiba species. 1. Miridiba kuraruana; 2. Miridiba huesiotoi, holotype; 3. Miridiba taoi, holotype; 4. Miridiba formosana; 5. Miridiba taipei, holotype; 6. Miridiba sinensis.

FIGURES 7 – 12. Dorsal view of head and upper half of pronotum of male Miridiba species. 7. Miridiba kuraruana; 8. Miridiba huesiotoi, holotype; 9. Miridiba taoi, holotype; 10. Miridiba formosana; 11. Miridiba taipei, holotype; 12. Miridiba sinensis.

FIGURES 19 – 24. Right metafemur of male Miridiba species. 19. Miridiba kuraruana; 20. Miridiba huesiotoi, n. sp.; 21. Miridiba taoi, n. sp.; 22. Miridiba formosana; 23. Miridiba taipei, n. sp.; 24. Miridiba sinensis.

FIGURES 25 – 32. Parameres of Miridiba species (25, 27, 29, 31, lateral view; 26, 28, 30, 32, dorsal view). 25 – 26. Miridiba kuraruana; 27 – 28. Miridiba huesiotoi; 29 – 30. Miridiba taoi; 31 – 32. Miridiba formosana. Scale bar = 1.0 mm.