4b. Bischoffitilla perakensis (Pagden, 1934)

(Figs 3, 39–41)

Squamulotilla perakensis Pagden 1934a: 448; Mickel 1935: 186.

Bischoffitilla perakensis: Lelej 2002: 127; Lelej 2005: 28; Okayasu et al. 2018: 306.

Diagnosis. FEMALE. This species can be recognized by a unique combination of characters: the genal carina is distinct and serrate or wavy; clypeus is tridentate, with the basomedial tooth as large as the apicolateral teeth; the mesopleural lamella is short, but distinct; the dorsoposterior propodeal row is distinct and complete; the posterior propodeal face is reticulate; and T3–5 each have a medial spot of whitish to golden setae. Other useful features include: antennal tubercle unarmed; mesosomal dorsum with complete, but sometimes weak, longitudinal carina; T1 apicomedially and T2 basomedially with white to golden spot; and T2 apically with complete transverse band of whitish to golden cuticle and/or setae. Body length 4.5–9.5 mm. MALE. Unknown.

Material examined (26 ♀). THAILAND: Chiang Mai: Doi Suthep, 1000 m, 18 o 48'N 98 o 55'E, 5.VII.1986, R. Hensen (1♀ RMNH); Omkoi District, Dry dipterocarp forest, 17°50′49.9″N 98°22′33.0″, 950–1010 m alt., 25.VI.2017, R. Mizuno (1♀ EUM); Kanchanaburi, Thong Pha Phum, Vimarndin farm stay, 14.655 o N 98.521 o E, 200 m, 17–20.V.2018, MKT (5♀ CSCA); Phetchaburi, Kaeng Krachan, Baan Maka Nature Lodge, 12.840 o N 99.590 o E, 140 m: 22–23.V.2018, MKT (3♀ CSCA); Surat Thani, Khlong Sok, Khao Sok Jungle Huts, 8.909 o N 99.526 o E, 70 m: 14.V.2018, MKT (9♀ CSCA EMUS MIUP QSBG); 25–26.V.2018, MKT (1♀ CSCA); Our Jungle House resort, 8.908 o N 99.534 o E, 75 m, 25–27.V.2018, MKT (7♀ CSCA).

Distribution. Thailand * (Chiang Mai, Kanchanaburi, Phetchaburi, Surat Thani), Malaysia (Perak).

Remarks. This species was described from Peninsular Malaysia (Pagden 1934a) and has been found in four Thai provinces. Using Chen’s (1957) key, this species would be identified as B. sauteri lingnani (Mickel, 1933), with which it may eventually be synonymized. The apparently diagnostic “serrate genal carina” varies within the series and can be found in other Bischoffitilla species, including B. cambrai sp. nov.