Journal of the Marine Biological Association of India

Volume 38 Issue 1&2

Investigations for confirming the status of two populations of Macrobrachium Equidens (Dana) (Palaemonidae)

Anitta Sebastian and K. V. Jayachandran

A lot of confusion exists in the taxonomic status of two populations, namely spotted and striped populations of Macrobmchium equidens (Dana, 1852). 'Ibe present paper established the differences in the length-weight relationship and meristic characters of these two populations. A comparison of the regression lines of males as well as females of the two populations showed significant differences in the length-weight relationships. The increase in weight of both sexes of the spotted variety and the males of striped variety was found to be slightly lower than the cube of its length. The analysis of meristic characters revealed that the spotted variety exhibited significant sexual dimorphism with regard to dorsal, ventral and post-orbital teeth whereas the striped variety exhibited significant difference between sexes only with regard to ventral teeth. A comparison of meristic characters between males of the populations and also between females showed that significant difference existed with regard to post-orbital and ventral teeth. Therefore the present study confirms that the two populations are quite distinct and are to be elevated to the species level.


Macrobrachium Equidens, length-weight relationship, meristic characters

Date : 30-12-1996