Scirtes babeldaobensis Yoshitomi

Yoshitomi, Hiroyuki, 2009, The Scirtes (Coleoptera: Scirtidae: Scirtinae) of Micronesia, Zootaxa 1974, pp. 1-16 : 12-13

Scirtes babeldaobensis Yoshitomi sp. n.

Figs. 1 E, 2E, 7

Type series. Holotype ( BPBM): male, “ Palau Babeldaob Is. 5-VIII-2002 K. Takahashi”. Paratypes ( BPBM, NMW, EUM): 1 male, “BABELTHUAP I. Palau Islands 12 Dec. 1947 ”, “wooded valley SW. of Ulimang”, “Pacific Sci. Board Ent. Surv. of Micronesia H. S. Dybas leg.”, genitalia on slide no. HY 927; 1 female, “Garakayo I. Pelew Islands VIII: 7: 45”, “Col. pres. by Henry & Dybas Lot 2474”; 2 females, “NGIRA- MAOUS I. Palau Islands 16 N 1947”, “Pacific Sci. Board Ent. Surv. of Micronesia H. S. Dybas leg.”, genitalia on slide no. HY 1074; 2 males, “E. Ngatpang 65m. Babelthuap Is Palau Palau. III-10-52 ”, “Caroline Is. Pac. Sci. Bd. J. L. Gressitt”.

Description. Male. Body oblong-oval, slightly convex above, dully shining, closely covered with short yellowish-white setae throughout. Color of body yellowish-brown, but head, scutellum, antennal segments IV–XI, lateral parts of elytra infuscate; mesal parts of elytra with mottled pattern.

Head large, slightly convex above, strongly and closely covered with large punctures; clypeus long, subparallel-sided, anterior margin distinctly concave. Labrum small, hidden under clypeus. Eyes moderate in size, weakly prominent; the distance between eyes about 2.4 times the maximum diameter of an eye. Antennae ( Fig. 2 E) stout, very long, lightly serrate in segments IV–IX, exceeding proximal 1/2 of elytra; approximate ratio of each antennal segment (n = 1) as 2.5: 1.0: 1.0: 1.9: 2.4: 2.6: 2.8: 2.6: 2.4: 2.1: 2.5. Pronotum slightly convex above, punctate as head; anterior margin almost straight; antero-lateral corners about 120º, slightly projecting anteriorly; lateral margins gently arcuate; postero-lateral corners 120º, rounded; posterior margin gently and evenly arcuate; PW/PL 2.00–2.09 (2.05). Scutellum small, an equilateral-triangle, punctate as head. Elytra oblong, widest at the middle, punctate as head; shoulders lightly elevated; EL/EW 1.43–1.57 (1.47); EL/PL 3.84–4.00 (3.94); EW/PW 1.25–1.36 (1.31); TL/EW 1.80–1.97 (1.85). Hind coxal plates subquadrate, posterior margin shallowly concave. Legs long. Hind tibial spurs long, curved outward in apices, closely covered with minute setae; dorsal spurs about 2.0X length of ventral spurs, about 0.8X length of hind tarsal segment I. Sternites III ( Fig. 7 A) sparsely covered with short setae; sternite IV sparsely covered with short setae irregularly, with a pair of extra tufts ( Fig. 7 B) paramedially; sternites V–VII closely covered with somewhat long setae.

Caudal margin of sternite VII ( Fig. 7 A) shallowly concave. Tergite VII with a pair of short apodemes; tergites VIII–IX trapezoidal, with a pair of long apodemes. Tegmen ( Fig. 7 C) small, moderately sclerotized, Y-shaped; basal part long and slender; parameres somewhat broad, as long as basal part, serrate in mesal parts, obtuse at apices, which is covered with fine punctures. Penis ( Fig. 7 D) moderately sclerotized, asymmetrical, 1.1X length of tegmen; pala oblong, widest at basal 1/3; apical part with two projections; shorter one (parameroid) protruding from dorsal part of basal 1/2, pointed at apex; longer one (trigonium?) protruding from caudal part, tapered posteriad, obtuse at apex.

Female. Sexual dimorphism distinct in the following characters: 1) front margin of clypeus shallowly concave; 2) antennae short and slender, reaching about proximal 1/3, not serrate in segments IV–IX; 3) coloration of body somewhat paler. Approximate ratio of each antennal segment (n = 1) as 2.7: 1.3: 1.0: 1.9: 1.9: 2.1: 2.1: 2.1: 1.9: 1.7: 1.9. PW/PL 2.08; EL/EW 1.45; EL/PL 4.23; EW/PW 1.40; TL/EW 1.79.

Measurements. Male (n = 4): TL 1.97–2.25 (2.08) mm; PW 0.80–0.92 (0.86) mm; PL 0.40–0.45 (0.42) mm; EL 1.57–1.80 (1.66) mm; EW 1.00–1.25 (1.13) mm. Female (n = 1): TL 2.51 mm; PW 1.00 mm; PL 0.48; EL 2.03; EW 1.40 mm.

Distribution. Palau (Babelthuap, Pelew and Ngiramaous Isls.).

Remarks. This species is similar to Scirtes zerchei Klausnitzer (2006) in the male genitalia, and differs from it by the following characteristics: (i) tegmen with obtuse apex of parameres (pointed in zerchei ); (ii) parameroid almost straight (curved laterally in apical part in zerchei ).

Etymology. The species is named after the type locality, Babelthuap (= Babeldaob) Island.

Figures

FIGURE 1. Holotype of Scirtes spp. A) Scirtes micronesianus sp. n.; B) Scirtes tinianensis sp. n.; C) Scirtes palauensis sp. n.; D) Scirtes gressitti sp. n.; E) Scirtes babeldaobensis sp. n.; F) Scirtes albotaeniatus sp. n. Scale bar = 1.0 mm.

FIGURE 2. Antennae of Scirtes spp. (above: male, under: female). A) Scirtes micronesianus sp. n.; B) Scirtes tinianensis sp. n.; C) Scirtes palauensis sp. n.; D) Scirtes gressitti sp. n.; E) Scirtes babeldaobensis sp. n.

FIGURE 7. Scirtes babeldaobensis sp. n., paratype, male. A) sternites I – VII; B) extra setae on sternite IV; C) tegmen; D) penis.