Breeding and fecundity of Praunus inermis [Crustacea, Mysidacea]

Abstract

Praunus inermis (Rathke) breeds at all times of the year in the Clyde, the pro-portion of breeding females being minimal in January and maximal in August. The progeny produced by the winter stock during the period March to July are known as the summer generation, the eldest members of which commence breeding in July/August, and the new winter stock is formed in the autumn from the surviving members of this generation and their progeny. The number of young carried in the marsupium varies seasonally, being about 30–40 in May/June and 10 during the period November to January. Larger females tend to carry more young than smaller females. Comparisons are made between the population in the Clyde and those at Port Erin, Isle of Man, and at Nyborg Fjord, Denmark.