Reproductive biology of the freshwater palaemonid prawn, Macrobrachium lanchesteri (De Man, 1911) from Myanmar.

Macrobrachium lanchesteri is presumed to be one of the most common and widely distributed freshwater prawns inhabiting still or slow-moving waters in Myanmar. The reproductive biology of M. lanchesteri from the Zaw Gyi River and Taung Ta Man Lake in central Myanmar was studied based on the occurrence of ovigerous females and eggs in different developmental stages. The total numbers of specimens studied were 1307 from Zaw Gyi River and 757 from Taung Ta Man Lake. Ovigerous females were captured throughout the year. A higher percentage of ovigerous females was obtained from June to November. Carapace length of ovigerous females ranged from 6.3 to 12.5 mm and egg size (length) varied from 0.8 to 1.0 mm. Compared to other species, the eggs of M. lanchesteri are larger than those of M. olfersii (0.4-0.6 mm) and smaller than of M. lamarrei (1.1-1.5 mm). More than half of the eggs were still at an early stage of development for every month sampled. The incubation interval of the eggs was estimated to be less than one month, because of the presence or absence of eggs in the eyed stage during the period from February to March. [ABSTRACT FROM AUTHOR]