Cephennomicrus taiwanensis

Jałoszyński, Paweł, 2009, Cephennomicrus Reitter (Coleoptera, Staphylinidae, Scydmaeninae) of Japan and Taiwan: taxonomic notes, ten new species and comparative morphology of nomurai and taiwanensis species groups, Zootaxa 2145, pp. 1-35 : 8-9

taiwanensis species group

This group is established for species with very elongate aedeagus, which in ventral view is about 3x as long as broad, with asymmetrical internal armature composed of a tubular median duct with its median part surrounded by slightly or strongly asymmetrical structures forming a central complex. These characters are unique within the genus. Additionally, all species in this group share the following combination of characters: the antennal club composed of small antennomere IX and very large antennomeres X–XI; mandibles in both sexes with a long apical tooth; the head in both sexes with frontal glands, non-modified in males; the base of pronotum with four pits forming two lateral pairs, without grooves; setae covering the dorsum very short and nearly recumbent, additionally the pronotum with three pairs of long setae located near the broadest place, in hind angles and in median part of the posterior margin, opposite anterior corners of the mesoscutellum; the elytra with similar, several (minimum 3) pairs of long setae along lateral margins; male with very small, hardly noticeable median tubercle in posterior part of the metaventrite.

This lineage comprises six species known from the Ryukyus and Taiwan: C. taiwanensis , C. iriomotensis sp. n., C. nagoanus sp. n., C. tsurui sp. n., C. delicatissimus sp. n., and C. imago sp. n.

Cephennomicrus taiwanensis (Jałoszy ń ski, 2004) ( Figs. 15 , 21, 22)

Neseuthia taiwanensis Jałoszyński, 2004: 158 , Figs 1–6 . Cephennomicrus taiwanensis ; Jałoszyński, 2008: 34.

Type material. Holotype: TAIWAN: 3, Taipei County, Fu-Shan ( HNHM).

Distribution. Known only from the type locality, Taipei Hsien in Northern Taiwan.

Remarks. This species is difficult to distinguish from other members of the taiwanensis group by external characters; subtle differences in the general body shape ( Fig. 15 ) exist, but they are possible to notice only by direct comparison. The combination of characters unique for C. taiwanensis is as follows: large punctures on the pronotum; three lateral setae on each elytron; and the aedeagus (Figs. 21, 22) with long and narrow central complex, and a complicated system of ducts. The median duct is bent twice at sharp angle, the basal loop is present, and the median loop is small and nearly closed. Moreover, this species has very slender parameres, with particularly thin apical parts, and each bears one apical and one subapical seta; the latter one is distant from the apex. The base of the parameres in the only known specimen is barely visible; reexamination with a phase-contrast microscope revealed that it is similar to that in all other species of this lineage. Despite moderate body length within the group, C. taiwanensis has the longest aedeagus in this distinct lineage.

Figures

FIGURES 15 – 20. Dorsal view of Cephennomicrus (holotypes, males). 15, C. taiwanensis (Jałoszyński). 16, C. iriomotensis Jałoszyński. 17, C. nagoanus Jałoszyński. 18, C. tsurui Jałoszyński. 19, C. delicatissimus Jałoszyński. 20, C. imago Jałoszyński. Scale bars: 0.2 mm.

FIGURES 1 – 5. Dorsal view of Cephennomicrus (male holotypes). 1, C. nomurai (Jałoszyński & Hoshina). 2, C. disjunctus (Jałoszyński, S. Arai & K. Arai). 3, C. inflatus Jałoszyński. 4, C. crucifer Jałoszyński. 5, C. hobbiti (Jałoszyński & Hoshina). Scale bars: 0.2 mm.

FIGURES 6 – 9. Aedeagus of Cephennomicrus in ventral (6, 8) and lateral (7, 9) views. 6, 7, C. inflatus Jałoszyński. 8, 9, C. crucifer Jałoszyński. Scale bars: 0.1 mm.