Bryothinusa japonica Liu, Ono & Maruyama, 2020

Liu, Tiantian, Ono, Ki. & Maruyama, Munetoshi, 2020, A new species and new record of the intertidal rove beetle genus Bryothinusa Casey (Staphylinidae: Aleocharinae: Myllaenini) from Japan, Zootaxa 4743 (4), pp. 585-593 : 586-588

Bryothinusa japonica Liu, Ono & Maruyama sp. nov.

[Japanese name: Nippon-nagisa-hanekakushi]

(Figs. 1, 3–11)

Type series. Holotype: 1♂, [ Japan]: Kyûshû : Mouth of Sakurai-gawa , Shima-Nogita , Itoshima-shi , Fukuoka-ken, 11 X 2018, Tiantian Liu . Paratypes: Honshû: 3♂, 6♀, 11 sex?, Obitsu-gawa, Kuzuma, Kisarazu-shi , Chiba-ken , 12 III 2009, H. Ono ; 2♂, 1♀, 1 sex?, same locality, 1 IV 1997, M. Maruyama ; 2♀, Miya-gawa, Iso-chô, Ise-shi , Mie-ken , 8 VI 2008, K. Akita; 1 sex?, Kushida-gawa, Matsuzaka-shi , Mie-ken , 7 IV 2001, T. Wada ; 1♂, 1 sex?, same locality, 28 IV 2002, Y. Kawakami; 1 sex?, same locality, 29 IV 2002, Y. Kawakami ; 1♀, 1 sex?, Nishinakajima, Ôsaka-shi, Ôsaka-fu , 18 IV 2003, Y. Kawakami; 3 sex?, Nanko-yachoen , Suminoe-ku , Ôsaka-shi , Ôsaka-fu , 27 III 2002, Y. Kawakami; 2 sex?, Yodo-gawa , Jûsô , Ôsaka-shi , Ôsaka-fu , 17 IV 2003, Y. Kawakami ; 2♀, 32 sex?, Himeshima Yodo-gawa, Nishiyodo-gawa-ku, Ôsaka-fu , 12 IV 2002, Y. Kawakami ; 1♂, 4♀, 21 sex?, Hanakawa Yodo-gawa, Nishiyodo-gawa-ku, Ôsaka-fu , 25 IV 2002, Y. Kawakami ; 1♀, 2 sex?, Mouth of R. Kako-gawa, Kak- ogawa-shi, Hyôgo-ken , 25 IX 2000, Y. Kawakami ; 1♀, Kôshien-hama, Nishinomiya-shi, Hyôgo-ken , 29 IV 2003, Y. Kawakami ; 2♂, 1♀, 19 sex?, Ômae-hama, Nishinomiya-shi, Hyôgo-ken , 11 IV 2002, Y. Kawakami ; 1♀, 3 sex?, Kariya Naka-gawa, Mitsu-chô, Ibo-gun , Hyôgo-ken , 5 X 2002, Y. Kawakami ; 1♂, 1 sex?, Arida-gawa, Miyazakichô, Arida-shi , Wakayama-ken , 28 V 2002, Y. Kawakami ; 1♂, 5 sex?, Mouth of R. Kino-kawa, Arimoto , Wakaya- ma-shi, Wakayama-ken , 26 IV 2001, Y. Kawakami; 1 sex?, Uji Kino-kawa, Wakayama- shi, Wakayama-ken, 10 VI 2002, Y. Kawakami ; 1♀, Fujino-gawa, Yamaguchi-shi, Yamaguchi-ken , 3 IV 2003, T. Wada; Shikoku : 2♂, 2♀, 3 sex?, Minato-gawa, Higashi kagawa-shi, Kagawa-ken , 5 IV 2008, H. Fujimoto .; 1♀, 17 sex?, Doki-gawa-Kakô, Doki-chô, Marugame-shi , Kagawa-ken , 29 VII 2000, H. Fujimoto ; 1♂, 1♀, 96 sex?, Doki- chô, Marugame-shi, Kagawa-ken , 15 IV 2001, H. Fujimoto ; 1♂, Doki-gawa, Fujimi-chô, Marugame-shi , Kagawa-ken , 27 V 2003, T. Watanabe; 1 sex?, Ôyatomi-machi , Sakaide-shi , Kagawa-ken , 29 III 2008, H. Fujimoto; 1 sex?, Shôsaka , Sogishohigashi , Ayagawa-chô , Kagawa-ken , 29 III 2008, H. Fujimoto ; 3♀, 3 sex?, Higashihabu-machi, Matsuyama-shi, Ehime-ken , 16 VI 2007, H. Suenaga; Kyûshû : 4♂, 7♀, 3 sex?, same locality as holotype; 14 sex?, same locality as holotype, 3 VI 2019, T. Liu & W. Liang ( Figs. 21 ) .

Distribution. Japan (Honshû, Shikoku, Kyûshû)

Description. Body (Figs. 1) small, more or less parallel-sided. Integument densely covered with pubescence. Abdomen almost black and darker than head and pronotum; elytra lightest; legs yellowish brown.

Head: evenly rounded, more or less produced anteriorly, wider than long; eyes large, setae present between about 21–24 facets, slightly longer than tempora; antenna yellowish brown, longer than head and pronotum combined; antennomeres VI–X almost as long as wide.

Mouthparts (Figs. 3–7): labral seta, shape as in Figure 3. Mandibles (Figs. 4) elongate, asymmetrical, right with median tooth, on left tooth absent, and blunt at apex. Maxillary apical margin of lacinia (Figs. 5) sinuate at right angle; at tip two spines closely interdigitating. Labial palpus (Figs. 6) with most setae distributed basally. Mentum (Figs. 7) with antero-lateral angles prolonged into spinose processes; anterior margin deeply truncate; small v setae remote from apical setae.

Pronotum: slightly wider than long, narrowest at base, basal margin slightly rounded; hypomera entirely visible in lateral view.

Elytral: hind wings reduced.

Abdomen: Female abdominal sternite VIII wider and smoother than male on posterior margin.

Median lobe of aedeagus (Figs. 8) with some granules in face of paramere at apical lobe, and which entirely visible in lateral view (Figs. 9). Paramere (Figs. 10) with apical lobe short. Inner wall of spermatheca (Figs. 11) roughly wrinkled, with some granule-like projection at posterior tip.

Measurements: BL 1.8–2.3 mm, FBL 0.8–1.1 mm, HL 0.25–0.38 mm, HW 0.35–0.40 mm, PL 0.30–0.40 mm, PW 0.35–0.46 mm, EL 0.30–0.41 mm, EW 0.36–0.45 mm, HTL 0.33–0.36 mm, AL 0.67–0.86 mm, AS-I 0.11–0.14 mm, AS-II 0.09–0.11 mm, AS-III 0.04–0.06 mm.

Diagnosis: The species in general appearance is closely similar to B. nakanei , but easily distinguished from it by the hind wings reduced while those of B. nakanei are well-developed, and by the spermatheca 1.5 times coiled near base while that of B. nakanei 2.5 times coiled near base. The detailed redescription of B. nakanei will be provided in our revision (Liu et al. in prep.).

Remarks: In Itoshima-shi of Fukuoka-ken, B. japonica and B. koreana were collected together under stones with dead barnacles at an estuary near the sea ( Figs. 21 ). This species is quite common in sandy to mud flats in estuaries in Japan, mainly west of Kantô District.

Figures

FIGURE 21 Collection locality Bryothinusa koreana Ahn & Jeon, 2004 and B. japonica sp. nov. in Itoshima-shi, Japan.