Amphicoma formosana Miyake

Li, Chun-Lin, Wang, Chuan-Chan & Chen, Hou-Jay, 2011, Synopsis of the genus Amphicoma Latreille (Coleoptera: Glaphyridae) of Taiwan with special reference to the male genitalia, Zootaxa 2790, pp. 23-34 : 32-33

Amphicoma formosana Miyake

Figs. 5–7 , 10 , 13 , 18 , 19, 22 , 26

Amphicoma formosana Miyake, 1982: 173 (type locality: Paoshan, southern Taiwan. holotype not located); Nikodým 2005: 26 (key and name list); Nikodým & Bezdēk 2006: 98 (catalog).

Amphicoma formosana f. kobayashii Miyake, 1982: 173 (unavailable infrasubspecific name)

Specimens examined. TAIWAN. Hwalien: Tze En, 29-VI-1996, S. H.Yen. (2 males, 2 females).

Redescription. Male. Body length 11.0–12.0 mm, width across humeri 2.9–3.0 mm. Body dorsal surface and venter of thorax varying in color form: metallic green ( Fig. 5 ) sometimes with violet undertones, violet blue, and/or reddish purple ( Fig. 6 ). Pygidium blackish brown with dull metallic reflection. Legs black. Antennae blackish brown. Dorsum overall densely setose, setae on disc of head and pronotum black to blackish brown; lateral sides of pronotum with longer yellowish brown setae; elytral surface densely covered with shorter, yellowish brown setae sparsely intermixed with about 1.0–1.5 times longer stout, black setae. Head: Surface densely rugopunctate, punctures large, each with an erect seta. Anterior margin of labrum weakly bilobed with anterolateral angles rounded. Clypeus rectangular, longitudinally weakly convex medially, slightly widened basally; anterior angle rounded; margins of clypeus thinly beaded, anterior margin sometimes unbeaded. Clypeofrontal suture medially, obtusely bent. Frons narrowed basally with a medial longitudinal suture. Eye canthi fringed with long blackish brown setae. Antenna with 10 antennomeres with club subequal width to length of stem. Thorax: Pronotum widest at anterior one-third, oval in shape, anterior angles weakly to moderately developed with basolateral angles rounded, lateral margin slightly explanate on basal one-third, middle of basal margin emarginate; setiferous punctures densely distributed over surface, punctures smaller, more well defined than those on head. Scutellum elongate triangular, flat, apex rounded, with fewer punctures than on pronotum. Prosternal process ( Fig. 10 ) protruding with inner margin strongly concave; metasternum with midline impressed, well defined; venter of thorax covered with long, yellow setae. Elytra: Disc surface flat with sutural margins slightly raised apically, disc surface densely rugopunctate; ridge-like epipleura thinly developed, gradually narrowed apically. Abdomen: Pygidial width 2.4 times length medially; disc flat, covered with long setae. Sternites 1–6 with surface setose. Legs: Protibia tridentate, basal teeth sometimes vestigial. Protarsi pectinate with tarsomeres 1–4 strongly condensed in length. Surface of profemora, mesofemora and metafemora densely covered with long setae similar to those on thorax. Mesotibiae and metatibiae with fine setae on inner sides and more robust setae along outer sides. Mesotibia with one inner apical spur subequal in length to half of basal mesotarsomeres, basal mesotarsomere 2.1–2.2 times as long as second mesotarsomere. Male genitalia: Parameres ( Figs. 13 , 18, 19 ) somewhat asymmetrical. Basal piece extension reaching basal one-fourth of paramere ( Fig. 13 ). Ventral plate ( Fig. 22 ) of genital capsule broadly widened, acutely curved at apical one-third; median stria well developed. Temones strongly twisted twice and fused apically; minor sclerite longitudinally lying within base of flagellum; base of flagellum abruptly broadened with margins reflexed, flagellum longer than paramere and subequal in length to halve of basal piece ( Fig. 26 ).

Female ( Fig. 7 ). Body length 13.0–13.7 mm, width 3.8–4.4 mm. Similar to male with same body color, differing in the following characters: body more robust, dorsum lacking yellowish brown setae with less dense puncture; antennal club width less than half of length of stem; anterior labrum moderately bilobed; clypeus longitudinally ridged, margins completely beaded; apex of mesotibia bearing two spines without incision; pygidium smaller in size; mesotarsi and metatarsi more robust and shorter.

Diagnosis. Amphicoma formosana can be distinguished by (1) reddish purple, metallic green or violet blue dorsal body color; (2) setae on disc of head and pronotum black to blackish brown, lateral sides of pronotum with longer, yellowish brown setae; (3) clypeus convex medially, margins of clypeus thinly beaded, clypeofrontal suture medially bended into obtuse angle; (4) frons narrowed basally with a medial longitudinal suture; (5) male antennal club slightly curved inwardly, width subequal in length to stem; (6) pronotum oval in shape, lateral margin slightly explanate; (7) inner margin of prosternal process abruptly concave; (8) metasternal midline impressed; venter of thorax covered with long, yellowish setae; (9) epipleura thin, gradually narrowing apically; (10) pygidial width 2.4 times length medially; (11) basal piece extension reaching basal one-fourth of paramere; (12) ventral plate acutely curved at apical one-third; (13) median stria completely developed; (14) base of flagellum abruptly broadened with margins reflexed, longer than paramere.

Distribution. Taiwan.

Remarks. Adults of Amphicoma formosana are rarely observed in the field during early summer, May to June, in the mid-elevational montane areas of Taiwan ranging from 1200–1800 m. A closely allied species, A. splendens , is found in two remote Japanese islands, some 250 km east of Taiwan. These two species need to be further studied and diagnosed.

Figures

FIGURE 1 – 7. Dorsal habitus of Amphicoma species. 1. Amphicoma lalashanensis, holotype; 2. Amphicoma aurata, male; 3. Amphicoma aurata, male; 4. Amphicoma aurata, female; 5. Amphicoma formosana, male; 6. Amphicoma formosana, male; 7. Amphicoma formosana, female.

FIGURE 8 – 10. Left lateral view of prosternal process of Amphicoma species. 8. Amphicoma lalashanensis; 9. Amphicoma aurata; 10. Amphicoma formosana.

FIGURES 11 – 13. Dorsal view of male genitalia of Amphicoma species. 11. Amphicoma lalashanensis; 12. Amphicoma aurata; 13. Amphicoma formosana. Abbreviations: BP-ext = basal piece extension; FMaB = flagellum major body. Scale bar = 1.0 mm.

FIGURES 14 – 19. Parameres of Amphicoma male genitalia in lateral view. 14 – 15. Amphicoma lalashanensis; 16 – 17. Amphicoma auratas; 18 – 19. Amphicoma formosana. Abbreviations: FMaB = flagellum major body. Scale bar = 0.5 mm.

FIGURES 20 – 22. 20. Amphicoma lalashanensis genital capsule; 21. Amphicoma aurata ventral plate of genital capsule; 22. Amphicoma formosana ventral plate of genital capsule. Abbreviations: LLP = left lateral plate; MS = median sclerite; RLP = right lateral plate; VP = ventral plate. Scale bar = 0.5 mm.

FIGURES 24 – 26. Temones and flagellum of Amphicoma species. 24. Amphicoma lalashanensis; 25. Amphicoma aurata; 26. Amphicoma formosana. Abbreviations: FMaB = flagellum major body; MiS = minor sclerite; TE = temones. Scale bar = 1.0 mm.