Cephalobyrrhus amami, Yoshitomi, Hiroyuki, 2019

Yoshitomi, Hiroyuki, 2019, Revision of the genus Cephalobyrrhus of Japan and Taiwan (Coleoptera, Limnichidae), ZooKeys 817, pp. 61-72 : 68-69

Cephalobyrrhus amami sp. n. Figs 1 C–D, 2G, 4, 5 C–D Japanese name: Amami-oome-hoso-chibidoromushi

Type series.

Holotype (EUMJ): Male, [AM6] Akatsuchi-yama, Uken-son, Amami-Ôshima, Kagoshima Pref., Japan, 28.151853, 129.195539, ca. 107 m, 23.IV.2017, H Yoshitomi leg. Paratypes (EUMJ, NMW): 13 males & 2 females, same data as for holotype.

Diagnosis.

The new species C. amami sp. n. has a short and pointed median lobe and a long phallobase.

Description.

Adults. Body oblong, convex dorsally, shiny, densely covered with short golden setae. Coloration of body black; antennomeres I–II, maxillae, labial palpi and legs pale brown, but infuscate in apical part of tarsomeres V.

Head densely punctate, convex anteriorly between antennal insertions. Antennae (Fig. 2G) long, reaching at base of elytra; approximate ratio of each antennomere (n = 1) as 1.78: 1.22: 2.00: 1.11: 1.33: 1.11: 1.00: 1.11: 1.11: 1.00: 1.22. Pronotum punctate as in head; PW/PL 1.64-1.97 (1.81). Scutellar shield triangular. Elytra oblong, widest at middle, gently arcuate in lateral margins; irregular markings consisting of adpressed setae relatively distinct; EL/EW 1.47-1.56 (1.52); EL/PL 3.06-3.79 (3.41); EW/PW 1.21-1.27 (1.24); TL/EW 1.88-2.01 (1.96).

Male. Sternite VIII (Fig. 4D) membranous, slightly transverse. Sternite IX (Fig. 4E) with long lateral struts. Aedeagus long, 0.9 mm; phallobase long, widest at the middle, then weakly tapering posteriorly and anteriorly, with curved nasal projection; parameres relatively slender, weakly pointed at apices, 0.30 times as long as phallobase; median lobe slender, straightly tapering apically, pointed at apex, 0.89 times as long as parameres.

Female. Spiculum ventral (Fig. 4F) long, a little longer than ovipositor. Ovipositor (Fig. 4G) well sclerotized, long; coxite sharply pointed at apices; approximate ratio of coxite and baculus (n = 1) as 1.0: 3.8.

Measurements of adults (unsexed; n = 20). TL 3.15-3.65 (3.36) mm; PW 1.30-1.50 (1.38) mm; PL 0.70-0.90 (0.76) mm; EL 2.45-2.75 (2.59) mm; EW 1.60-1.83 (1.71) mm.

Distribution.

Amami-Ôshima.

Remarks.

This species is clearly distinguished from the other two known species in the region by the short and pointed median lobe and long phallobase.

Etymology.

The species is named after the type locality.

Biological notes.

This species lives in a natural forest near a small stream (Fig. 5C, D). The type series was collected from the surface of fallen rotten wood during the daytime. Immature stages are unknown.