Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Trypanosoma punctati Hasan and Qasim, 1962 from Channa punctatus Bloch in Kerala, India, with observations on its vector-phase development and transmission.

Abstract

T. punctati recovered from the blood of C. punctatus in Kerala, India, is described in detail, and its body measurements and ratios are given. Vector-phase development of the trypanosome was observed in the crop of laboratory-reared leech, Hemiclepsis marginata. The bloodstream forms transform into short flagellates; within 12 h pi these divide by binary fission to produce short epimastigotes. The short epimastigotes multiply by repeated binary fission, and later transform into long-slender epimastigotes, which develop into metacyclic trypomastigotes. On the 5th day of development, the metacyclics invade the proboscis sheath. The short epimastigotes, long-slender epimastigotes and metacyclic trypomastigotes were observed in the crop and the metacyclics in the proboscis sheath for more than 25 days. In an infected leech, fed once again with fresh, uninfected blood, the developmental cycle is repeated. This is possibly an adaptive feature to maintain the infection of the leech for a long period, the duration of which has not been determined. Experimental infection was obtained by allowing the infective leeches to feed on parasite-free C. punctatus. Attempts to transmit the infection to Clarias dussumieri dussumieri, Heteropneustes fossilis and Mystus malabaricus were unsuccessful. T. punctati has thus some degree of host-specificity. T. punctati is recorded for the first time from Kerala, and this is the first report on the vector-phase development and transmission of a trypanosome from an Indian freshwater fish.