Known only from the Ataran River system in Kayin state, Myanmar.

The Ataran forms the headwaters of part of the larger Salween drainage, and some of its tributaries extend across the nearby border into Thailand, where it’s known as the Kasat.

Type locality is ‘Stream ”Chon Son’ between Kyondaw and Phadaw, about 20 kilometers north…

This species has previously been considered synonymous with both O. ornatus and O. pulchellus but is currently considered to be distinct following (Tejavej, 2012).

It can be distinguished from congeners by a combination of characters including: small caudal spot presen…

Batasio spp. are obligate inhabitants of headwater streams and the upper reaches of smaller rivers characterised by shallow, fast-flowing, highly-oxygenated stretches of riffles and runs broken up by pools or cascades in some cases. Images of the Ataran correspondingly depict flowing sections of forest-shaded, seemingly well-oxygenated headwaters containing clear water, a mixed sand/rock substrate and lots of submerged driftwood/leaf litter.

This species is among the few members of the family to be exported for the aquarium hobby and we’ve also seen it on sale under various names such as ‘orange-banded stone catfish’, ‘orange micro bumblebee catfish’, ‘Burmese orange mini bee catfish’ or more simply ‘wasp catfish’. Though the majority of forms are yellowish to orange in colouration there appears to exist a bright red variant which to date we’ve only seen in photos.

Adult patterning of the different geographical forms can vary considerably though young specimens all possess 5 solid dark bars on each flank and are often confused with those species exhibiting a similar juvenile pattern, particularly B. kubotai. However the horizontal dark bars on the flanks in B. kubotai typically split at quite a young age and/or develop horizontally-orientated ‘peaks’ whereas those in B. histrionica remain solid for longer and the central bar usually has a pale spot at the top so forms a ‘y’ shape.

Appears to be endemic to headwaters of the Salween River basin around the border between Myanmar and Thailand. The type specimens were collected from the Megathat Chaung (Megathat stream) in the upper Ataran (known as the Kasat in Thai) River basin, Kayin/Karen State, Myanmar and another population was later discovered in the Hanthayaw River (Suriya in Thai), Tak Province, Thailand.

Prior to description this species was considered to represent, and traded as, A. rubidipinnis, but that species is apparently endemic to the lower Irrawaddy basin in Myanmar and unknown in the aquarium hobby.

Male individuals of A. pictilis, A. botia and A. mandalaysensis possess a suborbital slit rather than suborbital flap which immediately distinguishes…

A putatively undescribed species often imported and sold as G. sp. ‘burmanicus’. It first appeared in the trade during 2005 and has since been available on a sporadic basis, usually with a relatively high price tag. As well as its unique colour pattern, a primary diagnostic character is the presence of a proboscis-like rostral process between the eyes.

This apparently undescribed species has been available in the hobby since around 2006 and has been traded under several trade names of which others include ‘tri-band sumo loach’ and ‘chubby loach’.

The name ‘Sumo II’ is now in wide use to distinguish it from the real S. balteata since both have been traded as ‘Sumo loach’…

Interestingly some observations suggest that the character of the highest-ranked, or alpha, fish appears to affect that of the whole group though it must be said that scientific studies of botiid loach behaviour are virtually non-existent. It certainly seems that they display a degree of ‘personality’ with some specimens being naturally bolder/more aggressive than others. The alpha is normally the largest specimen within the group and often female.

Sound also appears to be an important factor in communication since these loaches are able…