Cherry barb

Abstract: The structures of the fertilizedegg envelope in threespecies of cyprinidae, leoparddanio (Brachydanio frankei), cherry barb (Barbustitteya) and white cloudmountain fish (Tanichthys albonubes) were investigated by light and electron microscopy. The fertilized eggs of all three species have colorless, transparent, spherical and non-floted type. The egg envelopes have a single micropylewhich is thought to the pathway of sperm in the area of the animal pole. Also, an outer layersof both cherry barband white cloud mountain fish areadhesive types, but in that of leoparddanio has non-adhesivetype. In leopard danio, an outer surface ofegg envelope is covered by mushroom-likestructure, that of cherry barb is arranged by button-like structure, and that of white cloud mountain fish isarranged by rod-likestructure. Inboth leopard danioand cherrybarb, the eggenvelopes consist of three distinct layers; an outer layer, a middle layer and an inner layer, and that of white cloud mountain fish hastwo layers. An innerlayer of egg envelopein leopard danio consist of 10 layers, cherry barb has 8 layers, and white cloud mountain fish has layers.

Abstract: 1. 1. The tissue specific patterns and ontogeny of sorbitol dehydrogenase (SDH, EC 1.1.1.14), lactate dehydrogenase (LDH, EC 1.1.1.27) and isocitrate dehydrogenase (IDH, EC 1.1.1.42) are reported for Barbus tetrazona (tiger barb), B. conchonius (rosy barb), B. nigrofasciatus (black ruby barb), B. titteya (cherry barb), B. sachsi (gold barb), and in interspecific hybrids where B. tetrazona is the maternal parent. 2. 2. The spatial and temporal expression of SDH, LDH and IDH isozymes in Barbus is consistent with those reported for other teleosts. 3. 3. As the genetic distance between the parentals used in forming the hybrid increases, allelic expression proceeds from synchronous to asynchronous, with an increasing delay in embryonic gene expression. 4. 4. These observations are consistent with the hypothesis that parental sensor genes differ in their response to maternally controlled regulatory signals; indicative of species specific effector/activator RNA molecule concentrations and sensor/receptor gene induction thresholds.

Abstract: The diversity of fishes in a small stream in the Mullegama-Habarakada area of Sri Lanka was studied. A total of 16 species belonging to nine families were recorded, of which three are endemic and two are exotic to the country. The threats to the area include habitat degradation as a result of release of waste water, unmanaged waste disposal, sand mining and algal blooms. The abundance of Cherry Barb Puntius titteya was very low during the study period. This species is likely to be extirpated from Habarakada, unless urgent conservation measures are taken.