Discoxenus kakizoei, Kanao, Taisuke & Maruyama, Munetoshi, 2015

Kanao, Taisuke & Maruyama, Munetoshi, 2015, Eight new species, a new record, and redescription of the genus Discoxenus Wasmann, 1904: The first record of termitophilous rove beetles in Cambodia (Coleoptera: Staphylinidae: Aleocharinae), Zootaxa 4044 (2), pp. 201-223 : 218-219

Discoxenus kakizoei n. sp.

( Figs. 15, 16 , 137–148 )

Type materials. Holotype: ♀, Bayon, Ankor Thom, Siem Reap, Cambodia, 20 VIII 2012, Maruyama M. leg. (Colony no. MMCB-T-2012-2-009) (abdominal segments VIII–X dissected off).

Paratypes: 1♀, North Wall of Preah Khan, Siem Reap, Cambodia, 19 VIII 2012, Maruyama M. leg. (Colony no. MMCB-T-2012-2-005) (completely dissected). 2♀♀, 0.76 km NE of Preah Kham, Siem Reap, 19 VIII 2014, Kakizoe S. leg. (Colony no. SK007).

Diagnosis. This species is distinct, and is distinguishable from other Discoxenus species by a combination of the following three character states: right mandible with a distinct and blunt tooth ( Fig. 141 ), macrochaetotaxy of abdominal tergites III–VIII (6, 6, 6, 6, 6, 6), and spermatheca with the basal part being shorter than the apical part ( Fig. 148 ).

Description. Head ( Fig. 137 ) approximately 1.4 times wider than long. Antenna ( Figs. 15, 16 , 138 ) with segment I rectangular; segment II as long as segment III, with 4 macrosetae; segment III short, trapezoidal; segment IV transverse, wider than other segments; segments V–XI successively narrowed distally; segments V– VI wider than long; segment VII subquadrate; segments VIII–X longer than wide; segment XI approximately 2.6 times longer than wide. Labrum ( Fig. 139 , left side) with anterior margin deeply concave at middle; median projection of apodeme with posterior margin truncate; 3 lateral setae present in ventral view ( Fig. 139 , right side). Mandibles ( Figs. 140, 141 ), covered with 30–40 pores. Left mandible ( Fig. 140 ) with adoral margin moderately convex at apical third. Right mandible ( Fig. 141 ) with a tooth broadly convex at middle of adoral margin, rounded apically. Maxillary palpal segment III approximately 2.3 times longer than wide. Mentum ( Fig. 142 ) approximately 3 times wider than long, covered with around 50 pores. Labium with prementum covered with approximately 16 pores.

Pronotum ( Fig. 143 ) covered with approximately 44 macrosetae, 6 minute setae present around anterior margin. Elytron ( Fig. 144 ) transverse, sparsely covered with several setae at anterolateral outer corner, 12 macrosetae present on disc. Metaventrite approximately 1.7 times as long as mesoventrite.

Tergites III–VI ( Fig. 15 ) with 1–2 setae laterally. Tergite VII with a row of 5–6 setae subapically. Tergite VIII ( Fig. 145 ) with posterior margin pointed, 3 pairs of macrosetae present at posterior margin, with 2 pairs of macrosetae around middle. Macrochaetotaxy of abdominal tergites III–VIII = 6, 6, 6, 6, 6, 6. Sternite III ( Fig. 16 ) with posterior half densely covered with setae. Sternites IV–V with posterior half sparsely covered with setae. Sternites VI–VII with a row of yellow setae at middle. Sternites III–VII with 6–10 macrosetae at posterior margin.

Male. Unknown.

Female. Sternite VIII ( Fig. 146 ) with 2 pairs of macrosetae at posterior margin and middle. Spermatheca ( Fig. 148 ) with apical part longer than basal part.

Measurement. Body length = average 1.82 mm (N = 1), pronotal length = average 0.60 mm (0.58–0.62 mm, N = 2), pronotal width = average 0.85 mm (0.83–0.86 mm, N = 2), elytral length = average 0.44 mm (0.43–0.45 mm, N = 2), elytral width = average 0.50 mm (0.49–0.51 mm, N = 2.

Etymology. The specific epithet is named after Mr. Shotaro Kakizoe of Kyushu University, who collected and kindly provided the specimens of this rare species.

Host species. Hypotermes makhamensis Ahmad, 1965 .

Figures

FIGURES 13 – 18. Habitus. 13 – 14. Discoxenus lucidus n. sp.: 13. Dorsal view, 14. Ventral view. 15 – 16. D. kakizoei n. sp.: 15. Dorsal view, 16. Ventral view. 17 – 18. D. katayamai: 17. Dorsal view, 18. Ventral view.

FIGURES 137 – 148. Discoxenus kakizoei n. sp.: 137. Head, 138. Antenna, 139. Labrum (left side = dorsal view, right side = ventral view), 140. Mandible, left, 141. Mandible, right, 142. Mentum, 143. Pronotum, 144. Elytron, right, 145. Tergite VIII, 146. Sternite VIII, 147. Tergites IX and X, 148. Spermatheca.