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This research establishes a new record of the freshwater Thiarid snail, Thiara scabra, collected from the River Nile and its branches at Qena governorate, Upper Egypt. The shell varies in size and form, pale brown in color with reddish-brown patches or spots arranged on the whole whorls. It has an elongated turreted shell with a high spire of 8½ whorls that regularly increase in size and descending step-like with distinct sutures. Whorls are often shouldered from above and rounded from below. A row of spines, sculptured with vertical ribs, bearing prominent spines directed obliquely outward are found at the beginning of each whorl. Its surface shows a rough spiral striation. On the body, a whorl near the umbilical region striation of strong ridge can be seen. The umbilicus is closed. The most proximal three spires are found to be eroded. Aperture is almost vertical, oval, pointed above, and rounded below. The peristome is not continuous. The two ends are connected by a white callus against the penultimate whorl; exterior margin sinuous projects forward with a round curve in the middle; it recedes in the upper end and lower part and its basal margin is somewhat channeled. Operculum is a horny dark brown; the nucleus is eccentrical as it is at the left lower corner. Growth lines fan out to the tip and to the side of the operculum. The soft parts show the usual parts of the gastropod body, which are the head, foot and the visceral mass. The head and foot of the active snail can be seen protruding out of the shell. The pallial organs are typically like thiarids in form and position.

Zooplanktons are major components in the trophic dynamics of freshwater ecosystems. The present study was carried out on the River Nile at Esna barrages, Upper Egypt which located between 25°19'03.5"N and 32°33'19.5"E. Samples were collected from six sites up and down stream of the barrage during one year extended from October 2018 till September 2019. The study revealed that the total number of zooplankton community collected was (36367 indv/m 3 ). The collected zooplankton could be assigned to three different groups (Cladocera, Copepoda, and Ostracoda) which included 37 species belonging to 27 genera that fall in 10 families. The highest value of total abundance of zooplankton was recorded during winter and the lowest value was recorded during summer. The total density of zooplankton community was recorded at site 1 which is located upstream (9396 indv/m 3 ), while the lowest value was recorded at site 4 (downstream) (4186 indv/m 3 ). Cladocera was the dominant group; it represented about 87.5% of the total density followed by Copepoda and Ostracoda. Taxa richness reached the highest peak value (29 taxa) at upstream, while the highest peak value was (25 taxa) at downstream. Shannon-wiener's diversity index ranged between (2.06) and (2.33) at upstream while it ranged between (1.95) and (2.45) at downstream.

Thiaridae, Gill, 1871, is a family of class Gastropoda that includes species that have been intensely studied because of their reproductive, medical, veterinary importance and life history strategies, and their capacity for successful colonization of new habitats worldwide (Srong et. al., 2011). Although understanding of Thiaridae has been increased in recent times (

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