AFAIU, Wallago leerii and micropogon look almost identical, so much that for the longest time, until recently, they were considered the same species.
Recently, a species that is now called micropogon was split off from leerii:
http://www.planetcatfish.com/common/species.php?species_id=698
-- Leerii is found in large upland rivers from Thailand to Indonesia.
-- Population from mainland Southeast Asia (Thailand, Laos, Cambodia and southern Vietnam) represents a different species recently described as W. micropogon...
1) mouth reaching only to anterior of eye
2) mandibular barbel shorter than pelvic fin
3) 12-16 gill rakers on first arch
4) 64-75 anal-fin rays
http://www.planetcatfish.com/common/species.php?species_id=1861
-- Micropogon is distinguished by the following characters:
-- 14-16 branchiostegal rays;
-- 14-16 gill rakers on first branchial arch;
-- 68-73 anal fin rays;
-- small gape extending to anterior margin of eye;
-- pelvic fin length 8.9-10.6% SL;
-- small eye, 8.7-10.1% HL;
-- maxillary barbels reaching to middle of pectoral-fin base;
-- rounded pectoral fin in which the fourth branched pectoral ray is the longest;
-- pectoral spine length 14.3-16.7% SL;
-- dark colored body with a few pale spots forming a mottled pattern; and
-- 63-65 vertebrae.
As you can see, no clear and obvious marker is available for laymen like us to tell that this is really micropogon we are looking at and not leerii.
