Exochomoscirtes nipponicus, Ruta & Yoshitomi, 2010

Ruta, Rafał & Yoshitomi, Hiroyuki, 2010, Revision of the genus Exochomoscirtes Pic (Coleoptera: Scirtidae: Scirtinae) 2598, Zootaxa 2598 (1), pp. 1-80 : 70-72

Exochomoscirtes nipponicus sp. nov.

( Figs. 14D , 57 , 58 )

Type material. Holotype, male ( EUM): “[ JAPAN] the Ryukyus / Iriomote-jima Is. / Aira-gawa / 6 – V – 1999 / T. SHIMADA leg.” [printed label]; “genitalia in slide / No. HY 1124” [printed & handwritten label].

Paratypes. Female ( EUM): “Botanical Garden / Banna, Ishigaki I. /Ryukyus / 16.IV.1974 / H. Makihara leg.” [printed label]; “Collection / of Ent. Lab. / Ehime Univ.” [blue, printed label]. Male ( EUM): “Mariudo, Irio / mote-Jima, / 27-III-1994 / M. Matsumara ” [handwritten label]; “Collection / of Ent. Lab. / Ehime Univ.” [blue, printed label]. Female ( EUM): “[RYÛKYÛ: Japan] / Mt. Omoto Ishigaki-shi / {Altitude: 150–200} / 7.V.2003 / T. Kurihara leg.” [printed label]; “Collection / of Ent. Lab. / Ehime Univ.” [blue, printed label]. Male ( EUM): “LOOCHOO / Is. ISHIGAKI / Takeda / 20.III.1962 / Y. Arita leg.” [printed label]; “Collection / of Ent. Lab. / Ehime Univ.” [blue, printed label]. Female ( EUM): “[RYÛKYÛ: Japan] /Riv. Aira Taketomichô / 29.IV.2003 / T. Kurihara leg.” [printed label]; “Collection / of Ent. Lab. / Ehime Univ.” [blue, printed label]. Female ( EUM): “(Light Trap) / Omoto / Ishigaki-jima / 25–29.III.1998 / H. Yoshitomi leg.” [printed label]; “ Collection / of Ent. Lab. / Ehime Univ.” [blue, printed label] .

Diagnosis. The species is similar to E. nahangensis sp. nov., but is distinctly larger, tergite 8 in males is much longer, and prehensor is widened in basal half (very narrow in E. nahangensis ).

Description. Holotype, male. Body elongate oval, TL/EW 1.6, slightly flattened, covered with suberect brown setae. Head, pronotum, scutellum, and elytra brown. Mouthparts, antennae and legs yellowish-brown, metafemora darkened, brown. Ventral surface brown.

Head with distinct punctation, punctures separated by ca. 0.5–1.0 diameter. Eyes big, protuberant; head 1.9 X wider than interocular space. Antennae filiform. Antennomere 1 subcylindrical, antennomeres 2 and 3 of subequal lengths, antennomeres 4–11 slightly shorter than combined length of antennomeres 2 and 3. Palpomeres of maxillary palpi slightly widened.

Pronotum moderately convex, covered with distinct punctation, similar to that on head, separated by ca. 1.0–1.5 diameters, anterolateral corners obtuse, slightly projecting anteriorly; lateral margins subtly rounded; posterolateral corners somewhat acute; base of pronotum bisinuate, with complete margination along basal margin; PW/PL 2.8. Scutellum punctured as on pronotum, equilaterally triangular. Angle between pronotum and elytra not marked in dorsal outline.

Elytra oblong, with slightly explanate lateral margins, widest at the middle, punctation stronger than on pronotum, punctures deep, separated by ca. 1.0 diameter; humeri well marked; EL/EW 1.3; EL/PL 5.5; EW/ PW 1.5.

Legs moderately long. Hind tibial spurs well developed, dorsal one weakly curved, unmodified, as long as 3/4 length of tarsomere 1, and over twice as long as ventral one; ventral spur almost straight.

Ventrite 1 with sparse setation in mesal portion, and short longitudinal ridge, ventrite 2 with basal row of big punctures. Apex of tergite 7 unmodified. Apex of ventrite 5 subtly emarginated.

Sternite 9 (L 0.52, W 0.43) oval, consisting of two subrectangular hemisternites, with moderately long setae at apical margin. Tergite 8 (L 0.90, W 0.47) moderately sclerotized, long, apical portion subtrapezoidal, bearing row of setae on apical margin, apodemes long, diverging basally; tergite 9 (L 0.80, W 0.43) small, moderately sclerotized, with wide apical portion, without apical setae, with a pair of moderately long apodemes diverging basally, apodemes fused anteriorly. Tegmen (L 0.72, W 0.45) large, well sclerotized, parameres straight, widening and incurved apically, apices with two large denticles, mesal process very narrow, reaching 1/3 of the length of parameres. Penis (L 0.45, W 0.14) small, elongate oval, parameroids slightly shorter than pala.

Female. Externally indistinguishable from male. Prehensor long (L 0.20), very narrow in distal portion, widened in proximal half, hooked in distal portion.

Variability. TL/EW (same in males and females): 1.5–1.6 (1.5).

Measurements. Males (n = 3): TL 4.20–4.75 (4.38), PL 0.65–0.80 (0.73), PW 1.83–2.15 (1.96), EL 3.60–

4.10 (3.82), EW 2.70–3.10 (2.88). Females (n = 4): TL 3.95–4.50 (4.23), PL 0.70–0.75 (0.71), PW 1.90–2.00

(1.94), EL 3.40–3.85 (3.65), EW 2.70–2.90 (2.83). Distribution. Japan, Yaeyama Isl. Etymology. Specific epithet refers to the terra typica of the species ( Japan). Remarks. Closely related to E. nahangensis (many similarities in morphology of genitalia).

Figures

FIGURE 14. Habitus illustrations of Exochomoscirtes. A) E. dilaticornis sp. nov., female; B) E. pectinatus sp. nov.; C) E. longispinus sp. nov.; D) E. nipponicus sp. nov.; E) E. nahangensis sp. nov.; F) E. arunachalensis sp. nov.; G) E. meghalayensis sp. nov. Scale bar = 2.0 mm.

FIGURE 57. Exochomoscirtes nipponicus sp. nov., male. A) sternite 9; B) tergite 8; C) tergite 9; D) tegmen; E) penis. Scale bar = 0.5 mm.

FIGURE 58. Exochomoscirtes nipponicus sp. nov., female, bursal sclerite and prehensor.