Plesiochara nitida Sawada, 1990

Inoue, Shûgo & Maruyama, Munetoshi, 2022, Revision of the genus Plesiochara Sawada (Coleoptera: Staphylinidae: Aleocharinae), Zootaxa 5165 (4), pp. 501-519 : 507-510

Plesiochara nitida Sawada, 1990

Japanese common name: Tsuya-kusabira-hanekakushi

( Figs 4A–F , 5 , 12B )

Plesiochara nitida Sawada, 1990 : [original description, type locality: Nikyu-kyo, nr. Kure, Hiroshima Pref.]; Smetana, 2004: 361 [catalogue]; Shibata et al., 2013: 106 [catalogue]; Schülke & Smetana, 2015: 505 [catalogue].

Redescription. Body elongate; head, thorax and abdomen dark brown; antennae dark reddish brown, with basal part paler; mouth parts and legs reddish yellow; elytra reddish yellow with posterolateral portion darker; head, thorax, abdominal sternites, elytra, and legs covered with setae rather densely; abdominal tergites sparsely covered with setae; dorsal surface of head and pronotum densely covered with reticulation; elytra weakly rugose; abdominal tergites glossy.

Head circular, slightly longer than or as long as wide; postocular parts roundly narrowed toward base; eyes ovate. Antennae slender, longer than a combination of head and pronotum; segments IV–V slightly longer than wide; segments VI–VII as long as wide; segments VIII–IX slightly transverse; segments X as long as wide; segments XI ovate.

Pronotum almost hexagonal, slightly wider than long; anterior margin widely rounded; lateral margin moderately rounded, narrowed more strongly to posterior than anterior; anterior corners rounded; posterior corners obtusely angulated; hypomera visible in lateral view, with posterior part of carina ( Fig. 12B ) directed to posterolateral corners obliquely.

Mesoventrite shortly carinate at base of midline; inner coxal process narrow, elongate, reaching to metaventrite process. Metaventrite with inner coxal process short, moderately narrow.

Elytra wider than long, longer and wider than pronotum, weakly diverging to posteriorly, widest near posterolateral corners; hind margin sinuate near posterolateral corners. Hind wings developed.

Abdomen moderately elongate, parallel sided; tergites III–VII with pores at basal impression; VIII tergite with posterior margin smooth, shallowly emarginate medially in both sexes. VIII sternum with posterior margin smooth, widely rounded in both sexes.

Legs slender, long (HTL/PL = 1.35–1.47); surface of fore and middle tibia not covered with spines; hind tarsal segments I longer than a combination of II and III.

Male: Median lobe of aedeagus ( Fig. 4B–E ) rather large; apical lobe rather thin, weakly curved dorsally at apex, narrower, rather strongly constricted in ventral view at basal 1/3; apical lobe in lateral view; sclerites 1 convex at posterior margin, widely emarginate at anterior margin; sclerites 4 (sc4) rather indistinct, located at posterior apex of sclerites 2.

Female: Spermatheca ( Fig. 4F ) with capsule ovate, longer than chamber.

Measurements. BL 4.7–5.9, FBL 2.57–3.20, HW 0.75–0.85, HL 0.76–0.86, PW 0.84–1.13, PL 0.80–1.03, EW 1.23–1.48, EL 0.99–1.27, HTL 1.10–1.39.

Specimens examined. JAPAN: Honshu: [Aomori Pref.]: 1unsexed, Shiroiwa, Osaki, Hirakawa-shi , 21. V .1994, T . Ozaki leg. (cI); [Yamagata Pref.]: 1 unsexed, Shirakozawa, Oguni-machi , 5. VI .2010, I, Matoba leg. (cI); [Fukushima Pref.]: 1 male, Noji-onsen, Fukushima-shi , 25.X.2003, T . Watanabe leg. ( KUM); 1 male, 2 female, Futamata-onsen, Tenei-mura , 19.X.2003 , S. Nomura leg. ( KUM); [Gunma Pref.]: 1 male, 1 female, Tamahara-kogen, Kamihocchi-machi, Numata-shi , 26.X.2003 , N. Kanai leg. ( KUM); 1 female, Narahara, Ueno-mura , 8.IV.2007, T. Horiguchi leg. ( KUM); 1 female, Akegasawa, Narahara, Ueno-mura , 30.IV.2007, T. Horiguchi leg. (KUM) ; 1 unsexed, Nagamine-koen, Shibukawa-shi , 16.IV.2003, N. Kanai leg. ( KUM) ; [Tochigi Pref.]: 1 female, Mt. Shibakusa-yama, Nikko-shi , 9.IV.1995, H. Ohkawa leg. ( KUM) ; [Kanagawa Pref.]: 1 female, Mt. Ôyama , 25.XII.1966, Y. Shibata leg. ( KUM) ; [Ishikawa Pref.]: 1 male, Hiraguri, Kanazawa-shi , 21.IV.1983, Y. Hayashi leg. ( KUM) ; [Fukui Pref.]: 1 female, Hakuba-dô cave, Ôno-shi , 22.VII.2001, W. Takahashi leg. ( KUM) ; [Yamanashi Pref.]: 1 male, near Dôsaka Tunnel, Dôshi-mura , 16.XI.1996, T. Watanabe leg. ( KUM) ; [Nagano Pref.]: 1 unsexed, Shimashimadani, Matsumoto-shi , 900 m, 7–10. VI.2008, H. Asaki leg. ( KUM) ; 1 unsexed, ditto, 800 m, 21–26. V.2008, H. Asaki leg. ( KUM) ; 2 unsexed, ditto, 800 m, 10–16, X.2008, H. Asaki leg. ( KUM) ; 2 male, 3 unsexed, Nagawa, Matsumoto-shi , 1500 m, 31.X–6.XI.2008, H. Asaki leg. ( KUM) ; 1 male, 1 female, Konami, Suwa-shi , 6.III.2021, T. Hashizume leg. ( KUM) ; [Kyoto Pref.]: 1 unsexed, Otokoyama, Yawata-shi , Kyoto Pref., 19.II.2011, T. Ito leg., by rotten vegetables trap (cI) ; [Nara Pref.]: 1 unsexed, Nara park, Nara-shi , 13.XII.1987, S. Takahashi leg. (cI) ; 1 male, Ôdaigahara, Kamikitayama-mura , 25. V –6. VI.1986, S. Naomi leg. ( KUM) ; [Wakayama Pref.]: 1 unsexed, Hirai, Kozagawa-chô , 22. V.2008, I. Matoba leg. (cI) ; [Okayama Pref.]: 1 male, 1 female, Mt. Taki-yama, Nagi-chô, Katsuta-gun , 500–700 m, 16.III.2003, Y. Fujitani leg. ( KUM) ; 1 male, ditto, 23.XI.2003, Y. Fujitani leg. ( KUM) ; 1 female, ditto, 7.XII.2003, Y. Fujitani leg. ( KUM) ; 1 female, ditto, 28.III.2004, Y. Fujitani leg. ( KUM) ; [Yamaguchi Pref.]: 1 female, Nodani, Tokuji-chô , 31.III.2004, Y. Fujitani leg. ( KUM) ; Shikoku: [Tokushima Pref.]: 2 male, 2 unsexed, Mt. Tsurugi-san , 15–17.X.1980, S. Naomi leg. ( KUM) ; unsexed, ditto, 19–20. VI.1981, S. Naomi leg. ( KUM) ; 11 unsexed, Mt. Maruzawa-yama, Ichiu-son , 1410 m, 11. VI –6.VIII.2000, M. Yoshida leg. ( KUM) ; 1 unsexed, Nishinô-no-Mizuana cave, Aioi-chô, Naka , 26.IV.1986, H. Bando leg. ( KUM) ; [Ehime Pref.]: 1 female, riverside of Fukumi-gawa river, Matsuyama-shi , 27.XI–3.XII.1986, M. Hiraoka leg. ( KUM) ; 2 unsexed, ditto, 27.XI–3.XII.1986, M. Hiraoka leg. ( KUM) ; Kyushu: [Saga Pref.]: 1 unsexed, Makishima-yama, Seto-chô , Imari-shi , 35 m, 24.II.2021, S. Kakizoe leg., from dog dung ( KUM) ; [Ôita Pref.]: 1 male, Taiko-bashi-no-ana cave, Kadota, Takeda-shi , 322 m, 26.IV–10. V.2008, K. Ito leg. ( KUM) ( KUM) ; Hirado Is.: [Nagasaki Pref.]: 1 male, 1 female, 2 unsexed, Mt. Yasuman-dake, Yamanaka-chô, Hirado-shi , 420 m, 16.II.2021, S. Kakizoe & S. Inoue leg., from dog dung ( KUM) ; Tsushima Is.: [Nagasaki Pref.]: 1 female, Meishinodan-yama, Uchiyama, Izuhara-machi, Tsushima-shi , 175 m, 20–21.II.2022, S. Kakizoe leg., from dog dung ( KUM).

Distribution. Japan: Honshu, Shikoku, Kyushu, Hirado Is., and Tsushima Is. ( Fig. 5 ).

Bionomics. The collecting records show that Plesiochara nitida is distributed in lowlands to mountainous areas. Adults appear in fall, winter, and spring (October–June) and are found in animal dropping and fallen leaves. Some specimens were collected in caves.

Diagnosis. Plesiochara nitida is similar to P. japonica and P. inflexa , but can be distinguished by genital parts: median lobe of aedeagus with apical lobe thin, weakly curved dorsally at apex; spermatheca with capsule ovate, large, longer than chamber.

Figures

FIGURE 4. Plesiochara nitida: A, dorsal habitus; B–C, median lobe of aedeagus, lateral view; D–E, ditto, ventral view; F, spermatheca.

FIGURE 5. Distribution of Plesiochara nitida: black star, type locality.

FIGURE 12. Posterior part of hypomera:A, Plesiochara japonica comb. nov.; B, P. nitida; C, P. rufula sp. nov.; D–F, P. inflexa sp. nov.: D, Nagahashi, Otaru-shi, Hokkaido Pref.; E, Wakasugi forest, Nishiawakura-son, Okayama Pref.; F, near Dôsaka tunnel, Dôshi-mura, Yamanashi Pref.