Morphobiological characteristics and taxonomic status of weather loaches (Misgurnus) in the Pad Bolshaya (Middle Amur River)

Abstract

Morphological signs (32 plastic and 7 meristic) and biological parameters (size, weight, age and sexual structure, fecundity) are considered for weather loaches of gen. Misgurnus inhabiting the Pad Bolshaya (Jewish Autonomous oblast), with the body length Ad 60.2-182.4 mm, body weigh 2.3-55.3 g, age 1-8 years and sex ratio about 1 : 1 (53 % males, 47 % females). Sexual dimorphism is found for antedorsal, anteventral and ventroanal distances, tail fin base length, base length and height of pectoral, pelvic and anal fins, and maximum body height. Ontogenetic variability of morphological indices in dependence on body length is detected for 26 of 32 plastic signs, whereas the dependence of anteanal, antedorsal, pectoventral, and anteventral distances, and maximum and minimum body height on the body length is not statistically significant. Males grow slower than females. Age of puberty is 4-6 years, mean individual absolute fecundity is 7409 eggs. The analysis concluded that the weather loaches Misgurnus in the Pad Bolshaya belonged to the species Misgurnus nikolskyi (Vasil’eva, 2001).