Pseudatheta thailandensis Pace, 1992

Hashizume, Takuto, Yamamoto, Shûhei & Maruyama, Munetoshi, 2023, Revision of the Genera Pseudatheta Cameron and Phymatura Sahlberg (Coleoptera, Staphylinidae, Aleocharinae) from Japan, Zootaxa 5319 (1), pp. 27-47 : 37-38

Pseudatheta thailandensis Pace, 1992

( Figs. 1D , 6B–D )

Pseudatheta thailandensis Pace, 1992: 239 (original description;

type locality: “Chiang Mai Prov., Doi Suthep”); Pace, 2004: 66 ( China, Shaanxi); Schülke & Smetana, 2015: 634 (catalogue).

Material examined. THAILAND: 2 males, 1 female, Doi Inthanon , Chaing Mai, 1560 m, 20 X 1983, M. Sakai leg. ( EUM) .

Additional description. Measurements (n = 1): BL ≈ 2.07; FBL: 1.22; HL: 0.36; HW: 0.43; PL: 0.52; PW: 0.60; EL: 0.43; EW: 0.72. Ratios (n = 1): HW/HL: 1.18, PW / PL: 1.44, EW/EL: 1.67, PW /HW: 1.39, EL/ PL: 1.03, EW/ PW: 1.20.

Relative length of antennomeres I–XI (n = 1): 20: 24: 15: 10: 12: 10: 12: 12: 12: 11: 34. Ratio of length/width of antennomeres I–XI (n = 1): 1.79: 2.36: 1.50: 0.68: 0.76: 0.65: 0.66: 0.63: 0.58: 0.55: 1.61.

Male. Elytra with a pair of small tubercles at about posterior 1/3 on sutural margin. Sternite VI with small medial lobe on posterior margin. Tergite VII with a tubercle on posteromedian area. Tergite VIII ( Fig. 6B ) with a tubercle on median area; four processes on each side of posterior margin, outer ones slightly curved, longer and sharper than the others. Aedeagus as in Fig. 6C ; median lobe with large basal bulb; apical process relatively slender, narrowed apically in lateral view, apex pointed; flagellum moderately long.

Distribution. Thailand, China (Shaanxi).

Remarks. This species was described only from a female and could not be distinguished from its allied species based on the spermatheca.According to the original description by Pace (1992), the median part of the spermatheca is short, but this description may have derived from a deformed specimen. In many aleocharine species, spermathecae are easily deformed immediately after mounting in mounting medium. Later, Pace (2004) recorded this species from China, but it was again a female specimen. In this study, we were able to examine specimens of both sexes of the genus Pseudatheta , which were similar to Ps. thailandensis collected in an area close to the type locality of Ps. thailandensis . Since there are areas where more than one species of this genus is distributed, such as Japan, whether these specimens are Ps. thailandensis is unclear. Nonetheless, since this species is the only known thailandensis -like species from Thailand, we tentatively identified the specimens as Ps. thailandensis and described the aedeagus.

This species can be distinguished from its allies ( Ps. crenulicauda , Ps. taiwanensis ) by the apical process of the aedeagus, which tapers gradually toward the apex. However, Ph. bigranipennis (Bernhauer, 1915) , redescribed by Benick (1980) and Kim & Ahn (2016), cannot be distinguished from Ps. thailandensis judging from the illustrations and description, and specimens described by the authors are considered identical. Since Benick (1980) and Kim & Ahn (2016) did not state that they examined the type specimen, we cannot rule out the possibility of a misidentification. Thus, we refrain from taxonomic treatment of Ph. bigranipennis at this time. The relationship between Ps. thailandensis and Ps. hilaris could not be determined.

Figures

FIGURE 1. Habitus of Pseudatheta spp. A. Pseudatheta crenulicauda (Bernhauer, 1907), comb. nov.; B. Pseudatheta taiwanensis Pace, 2008; C. Pseudatheta hilaris (Sharp, 1888), comb. nov., lectotype of Oxypoda hiralis; D. Pseudatheta thailandensis Pace, 1992; E. Pseudatheta cooteri Pace, 1998; F. Pseudatheta elegans Cameron, 1920. Scale bars: 1.0 mm.

FIGURE 6. Pseudatheta spp. A: Ps. hilaris (Sharp, 1888), comb. nov., B–D: Ps. thailandensis Pace, 1992. A, D. spermatheca; B. male tergite VIII in dorsal view; C. median lobe of aedeagus in lateral view. Scale bars: 0.1 mm.