BENTHIC COMMUNITIES Il\' THE NILE RIVER, EGYPT II- MOLLUSCA

BENTHIC COMMUNITIES Il\’ THE NILE RIVER, EGYPT

II- MOLLUSCA

BJ·
RAMADAN, SH. E.”‘; KHElRALLAH, A. M.

AND ABDEL-SALAM, KH. M.

*Nationallnstitute ojOceanography m1d Fisheries. Kayet-Bey. Alexandria. Egypt.
Key words: Ecology, Taxonomy, Mollusca, Nile River.
ABSTRACT
The present work is the second in a series titled ” Benthic
communities in the Nile River, Egypt”. It is the first work to deal
quantitatively with the ecology of the Egyptian Nile Mollusca in an
area extending for 805 lan. between Esna and Delta Barrage (El
Kanater El Khyria).
Monthly samples were collected from 9 localitieS selected along
the Nile stream to represent different ecological conditions.
.- . Twenty species of molluscan falma belonging to eighteen genera
affiliating to 13 families and three orders were recorded through the
present study. Fourteen of them are gastropods while the other six
species are bivalves.
The bivalve Corbicula consobrina was the most ablIDdant species
and its Absolute Importance Value (AIV) showed a peak in spring and
winter.
Type of sediment was the main factor affecting AIV in the area
investigated. Sandy mud or muddy sand bottom sustained populations
of molluscs more than the sandy or gravely sand bottom.