Pseudoligota antennata ( Bernhauer, 1907 ) Hashizume & Yamamoto & Maruyama, 2023

Hashizume, Takuto, Yamamoto, Shûhei & Maruyama, Munetoshi, 2023, Taxonomic notes on the genus Pseudoligota Cameron (Coleoptera: Staphylinidae: Aleocharinae) from Japan, Zootaxa 5227 (1), pp. 100-108 : 101-104

Pseudoligota antennata ( Bernhauer, 1907) , comb. nov.

( Figs 1A , 2A–C , 4A–B , 5A )

Oligota antennata Bernhauer, 1907: 388 (original description; type locality: Onsen [Unzen in Nagasaki-ken, Kyushu]). Oligota (Holobus) antennata: Bernhauer & Scheerpeltz, 1926: 512 (catalogue).

Holobus antennatus: Smetana, 2004: 453 (catalogue); Schülke & Smetana, 2015: 657 (catalogue).

Pseudoligota affinis Cameron, 1939: 147 (original description; type locality: Siwaliks: Nakraunda [ Northern India: Uttarakhand,

Nakraunda in ‘Siwaliks’ [= presumably city of Shivalik Nagar], Nakraunda Village.]); Smetana, 2004: 447 (catalogue); Pace, 2011: 29 (Eastern India: Orissa (currently Odisha )); Pace, 2012: 325 ( Malaysia: Pahang); Schülke & Smetana, 2015: 646 (catalogue). Syn. nov.

Material examined. Type material. Holotype: male, “Onsen. Japan / lg. Sauter. [handwritten] // antennata / Brh. Typ [handwritten] // Oligota antennata / Brh. Typus [handwritten] // Chicago NHMus / M. Bernhauer / Collection.” (abdominal segments VIII‒X and aedeagus were dissected and mounted in Euparal by MM) ( FMNH). See details on Fig. 4 .

Additional specimens studied. JAPAN: Hokkaido: [Hokkaido]: 4 exs., Kannonzawa-rindô , Toyama, Minami-ku, Sapporo-shi, 8 VIII 2021, T . Nozaki leg. ( KUM); Shikoku : [Ehime-ken]: 1 ex., Matsuyama Castle, Kuromon Trail, 17 V 2018, P. Jałoszyński leg. (pcPJ); Kyushu: [Ôita-ken]: 17 exs., Shônaichô-Asono, Yufu-shi, 20 V 2021, T . Hashizume leg. ( KUM); [Nagasaki-ken]: 3 exs., Mitsushimamachi-Sumo , Tsushima-shi, 11 IX 2021, T . Hashizume leg. ( KUM); [Kagoshima-ken]: 1 ex., Koseda , Yaku-shima Is., 22 VII 2021, T . Hashizume leg. ( KUM); 6 exs., Kurio , Yaku-shima Is., 21 VII 2021, T . Hashizume leg. ( KUM).

Diagnosis. This species can be distinguished from its congeners by a combination of the following characters: body black, antennae and legs yellow, elytra and male tergite VII unmodified, male tergite VIII with broad blunt median tooth at posterior margin, and the shape of the median lobe of aedeagus. Pseudoligota picea Pace, 2003 and P. picetoides Pace, 2003 have somewhat similar median lobes of the aedeagus, but males of these species have carinae or granules at sutural elytral margins and an elongate tubercle in the center of tergite VII.

Redescription. Measurements. (n = 5): BL 0.90–1.27; FBL: 0.52–0.66; HL: 0.17–0.20; HW: 0.26–0.29; PL: 0.19–0.25; PW: 0.38–0.46; EL: 0.19–0.26; EW: 0.43–0.56. (Holotype: BL ≈ 1.1; PL: 0.24; PW: 0.43; HTL: 0.24).

Body ( Fig. 1A ) black; legs and antennae excluding terminal segment yellow; antennal terminal segment darker than proximal segments.

Head. Transverse, about 1.50 times as wide as long. Sparsely punctured with indistinct shallow punctures. Antenna 11-segmented, segments I–III longer than wide, segments IV–V about as wide as long, VI–X transverse, segment XI 1.5 times as long as wide.

Thorax. Pronotum transverse, about 1.83 times as wide as long, widest at posterior angles, base rounded; punctures somewhat denser, more distinct than those of head; microsculpture indistinct. Elytra transverse, slightly wider than pronotum; punctures larger than those of pronotum; microsculpture slightly stronger than that on pronotum, composed of transverse reticulation; carinae or granules on sutural margins absent. Hind wings developed.

Abdomen narrowed posteriad, with punctures finer than those on elytra, with diamond-shaped reticulation. Tergite VII unmodified.

Male. Tergite VIII ( Fig. 2A ) with broad blunt median tooth at posterior margin. Median lobe of aedeagus ( Fig. 2B ) of complicated shape; parameral process bilobed, parameral lobe of parameral process long, apex pointed, bending paramerally in the apical 2/5; abparameral lobe short, apex rounded, exceeding the flexure of parameral lobe; long thin lobe on left side in abparameral view; flagellum very long, emerging to outside from behind the parameral process, basal part of flagellum relatively small and slightly oval.

Female. Similar to male in general appearance. Tergite VIII without broad blunt tooth at posterior margin. Spermatheca ( Fig. 2C ) simple; distal bulb rounded with tongue-shaped lobe, wall of the distal end protrudes inward; duct curved.

Distribution. Japan: (Kyushu; Hokkaido, Tsushima Is., Yaku-shima Is.—new record); India, Peninsular Malaysia.

Remarks. Pseudoligota antennata was originally described as Oligota antennata by Bernhauer (1907). Then, Holobus was given a full generic rank by Coiffait & Saiz (1967) and recently this species was catalogued as Holobus antennatus ( Smetana 2004; Schülke & Smetana 2015). However, after studying the holotype of Oligota antennata , it was determined that this species should belong to the genus Pseudoligota . Pseudoligota affinis was described from northernmost India by Cameron (1939). The original description of P. affinis (see Cameron (1939)) and illustrations of the aedeagus of P. affinis in Ashe (1984) are consistent with the characteristics of P. antennata , and the two species are indistinguishable. Therefore, P. affinis should be regarded as a junior synonym of P. antennata .

Bionomics. Most specimens were obtained from fungi on dead wood in deciduous and evergreen forests ( Fig. 5A–B ).

Figures

FIGURE 1. Habitus of two species of Pseudoligota from Japan. (A) Pseudoligota antennata comb. nov. (B) Pseudoligota nozakii sp. nov. Scale bar: 0.5 mm.

FIGURE 2. Pseudoligota antennata comb. nov. (A) male tergite VIII in dorsal view. (B) median lobe of aedeagus in lateral view. (C) spermatheca. Scale bars: 0.1 mm.

FIGURE 4. Holotype of Oligota antennata Bernhauer, 1907 (= Pseudoligota antennata comb. nov.). (A) habitus in dorsal view. (B) labels.

FIGURE 5. The living habitus and habitat of Pseudoligota spp. (A) P. antennata comb. nov. on fruiting body of fungi. (B) fruiting body of fungi from Fig. 5A on dead wood. (C) habitus of P. nozakii sp. nov. (D) fruiting body of fungi on dead wood from which P. nozakii sp. nov. was obtained. (C–D: photo by T. Nozaki, used with permission).