Siagotanyx rufa Ashe, 2005

Ashe, James S., 2005, Three new genera and four new species of aleocharine staphylinids with unusually long mandibles from Australia (Coleoptera: Staphylinidae: Aleocharinae: Homalotini), Zootaxa 1002 (1), pp. 21-44 : 27

Siagotanyx rufa Ashe , new species

( Figs 2 , 14–24 )

Type material. Holotype: male, with labels as follows: “AUSTL: Tas., Lk. St. Claire Nat. Pk. Nr. Echo Point, 11­II­1977 ”, “FMHD#77­130, Eucalyptus delegatensis litter at base of tree, J. Kethley”, “ HOLOTYPE: Siagotanyx rufa Ashe , design. J.S. Ashe, 2005” ( ANIC).

Paratypes: 2; same data as holotype (1 female FMNH, 1 female KSEM) .

Description. Length 2.3–2.5 mm. Body light reddish brown, meso­ and metathorax and abdomen darker brown, apical edges of abdominal segments slightly lighter and apical half of segment VII and segments VIII–X reddish brown. Head slightly broader than apex of pronotum; base of pronotum distinctly narrower than base of elytra. Antenna short ( Fig. 20 ), reaching slightly beyond base of pronotum when extended posteriorly, article 4 subquadrate, articles 5–10 transverse, each slightly wider than previous article; article 5 about 1.8 times as wide as long, article 6 about 1.9 times as wide as long, article 10 about 2.7 times as wide as long, article 11 slightly shorter than articles 9 and 10 together. Head and prothorax very finely and uniformly covered with fine punctures and short, yellowish microsetae; surfaces with very slight, weak microsculpture, surfaces glossy. Pronotum transverse, about 1.5 times as wide as long. Elytra with punctures larger than those on pronotum, moderate sized, average distance between punctures subequal to width of punctures. Abdominal terga and sterna with longer and more prominent microsetae, uniformly distributed. Abdominal terga III–VI with moderate transverse depression, V with shallow and VI with inconspicuous transverse depressions; depressions with numerous, uniformly distributed setigerous pores in transverse depressions fewer and more dispersed on tergum VI; tergum III with microsetae near apico­lateral margin curved medially. Hind tarsus with article 1 about 1.1 times length of articles 2 and 3 together; article 2 about 1.4 times length of article 3; articles 3 and 4 subequal in length; article 5 about 0.8 times length of article 1.

Secondary sexual characteristics: None apparent except males with anterior half of sternum VII with densely arranged micropores, and with sternum VIII very slightly produced as a broad triangular lobe.

Spermatheca: As in Fig. 22 .

Aedeagus: Parameres as in Fig. 23 . Medial lobe as in Fig. 24 .

Distribution. Known only from Lake St. Claire National Park in Tasmania, Australia.

Natural history and habits. All specimens were collected from Eucalyptus delegatensis litter at base of tree.

Discussion. This is currently the only species known in this genus.

Figures

FIGURE 2. Siagotanyx rufa Ashe, habitus dorsal, length, 2.4 mm.

FIGURES 14–18. Siagotanyx rufa Ashe. 14, labrum, dorsal aspect. 15, epipharynx. 16, right and left mandibles respectively, ventral aspect. 17, right maxilla, ventral aspect. 18, labium, ventral aspect. Scale bar = 0.1 mm.

FIGURES 19–24. Siagotanyx rufa Ashe. 19, mentum. 20, antenna. 21, meso­ and metasternum. 22, spermatheca. 23, aedeagus, paramere. 24, aedaegus, median lobe. Scale bar = 0.1 mm.