Live male paratype specimen. © Kowasupat et al.

Following the recent description of B. mahachaiensis, another new species of the Betta splendens species group from Thailand is described in the latest volume of the journal ‘Vertebrate Zoology’.

Formerly referred to as Betta sp. ‘Kabinburi’, it’s officially named B. siamorientalis due to its native range in the east of the country, and can be distinguished from other members of the group by the following set of characters: body dark brown to black; opercle black with two reddish, parallel vertical bars; opercular membrane dark brown to black with red markings; caudal-fin with red distal crescent and a thin black edge, and without dark transverse bars; distal portion of posterior anal-fin rays red with a small red marking at the distal tip; pelvic-fin coloured black and red between the proximal base and white tip.

It’s know only from the provinces of Chachoengsao, Sa Kaeo, Prachin Buri, and Chon Buri in Thailand, plus Banteay Meanchey province in Cambodia. Like other B. splendens-group members it builds a bubble nest when breeding and occurs in various types of sluggish to standing water bodies including marshes, flooded fields, rice paddies, ponds, lagoons, ditches, and canals.

For further information please refer to the full, open access paper: Kowasupat, C, B. Panijpan, P. Ruenwongsa and T. Jeenthong. 2012. Betta siamorientalis, a new species of bubble-nest building fighting fish (Teleostei: Osphronemidae) from eastern Thailand. Vertebrate Zoology 62(3): 387-397