First record of Tripartiella sp. (Ciliophora: Peritrichia) in Pseudoplatystoma corruscans (Osteichthyes: Pimelodidae) cultured in the state of mato grosso do sul, brazil, with the description of a new species

Abstract

This study describes a new species of Tripartiella Lom, 1959 (Ciliophora: Peritrichia), named T. pseudoplatystomae n.sp., in Pseudoplatystoma corruscans reared in Dourados, Mato Grosso do Sul, Brazil. Small-sized trichodinid with a disc-shaped body of 36.2+3.7 µm, adesive disc 31.9+3.6 µm and denticulate ring 17.3+1.3 µm in diameter, provided with 29.6+1.2 denticles. Denticle 3.5+0.6 µm, blade 5.9+0.8 µm, ray length 1.6+0.2 µm and central part 1.4+0.3 µm width; span 9.0+1.2 µm. These specimens were similar to T. cichlidarum, T. orthodens and T. dactylodentata. From T. cichlidarum differs in the number of denticles and length of ray; from T. orthodens differs in the number of denticles, length of blade and ray; from T. dactylodentata differs in the diameters of adhesive disc and denticulate ring, in the length of ray and ray apophysis; from T. microctenopomae and T. ctenopomae differ in the denticulate ring, number of denticles and length of ray. Tripartiella cichlidarum, T. orthodens and T. ctenopomae showed a ray stronger than the present description. The blade’s finger like appearance in T. dactylodentata and the blade’s triangular shape in T. cichlidarum confirmed the difference in relation to the present material. Comparative measurements of described species are also presented.