Exalloniscus thailandensis Dalens, 1987

Exalloniscus thailandensis Dalens, 1987 View in CoL

Figure 3

Exalloniscus thailandensis Dalens 1987: 45 View in CoL , pl. 2 figs 7-14; Taiti and Ferrara 1988: 357, figs 14, 15; Schmalfuss 2003: 113; Beron 2015: 182.

Exalloniscus bessoni Dalens 1992: 17 View in CoL , figs 1-16; Schmalfuss 2003: 112; Beron 2015: 182, n. syn.

Exalloniscus yinae Nunomura and Xie 2000: 61 View in CoL , fig. 9, n. syn.

Material examined

THAILAND: 3 ♂♂, 10 ♀♀ ( MZUF), Chiang Mai Province, Mae Tae, village Pamiang, Bat Cave , 19.VII.2018, leg. S. Polak.

LAOS: 3 ♂♂, 10 ♀♀, 5 juvs ( MZUF), Louangprabang Province, Kuang Si Waterfalls , ca. 30 km S of Luang Prabang, 19°44’58.0”N 101°59’31.6”E, 515 m a.s.l., with ants, 4.III.2007, leg. S. Taiti. GoogleMaps

Previous records

THAILAND: Nam Hu Hoa Koa Cave, 17 km from Mae Hong Son ( Dalens 1987); Chieng Mai Prov., Doi Inthanon National Park; Chiang daw ( Taiti and Ferrara 1988). LAOS: Luang Prabang, Tham Russi ( Dalens 1992). CHINA: Yunnan, Xishuangbanna, Tropic Botanic Garden ( Nunomura and Xie 2000).

Distribution Northern Thailand, northern Laos and southern China.

RemarksExalloniscus thailandensis was described by Dalens (1987) from specimens collected in a cave in north-western Thailand. Taiti and Ferrara (1988) added new figures of this species from specimens collected in Chang Mai Province, Thailand. The species is characterized by having colourless body, absence of eyes and complex male pleopod 1 endopod with a long pointed apical part recurved outwards and a triangular lobe on its outer margin. These and all the other characters are present also in the Exalloniscus bessoni View in CoL described by Dalens (1992) from a cave of Luang Prabang, northern Laos. Dalens stated that E. bessoni View in CoL is very similar to E. thailandensis but did not mention which differences distinguish the two species. The examination of several specimens from the same area in Laos allowed us to consider E. bessoni View in CoL as a junior synonym of E. thailandensis since all the characters described for E. bessoni View in CoL are present also in E. thailandensis , including the typical shape of the male pleopod 1. The male characters of the specimens from Luang Prabang here examined are illustrated in Figure 3. Moreover, also Exalloniscus yinae View in CoL , described by Nunomura and Xie (2000) from south-western Yunnan, China, close to the border with Laos, shows the same characters of E. thailandensis and is also considered to be a junior synonym of that species.