Caspian Anadromous Shad Alosa kessleri kessleri (Grimm, 1887) from the Akhtuba River, Lower Volga River Basin: Biological and Morphological Features

Data on the dynamics of anadromous migration, age composition, body length, body weight, and morphometric characteristics of Caspian anadromous shad from the Akhtuba River are presented. Currently, Caspian anadromous shad from the Akhtuba River is monomorphic; no temporal groups have been identified. The population is represented by medium-sized young early-maturing (age of 2–3 years) fish with life longevity less than 5 years. Generally, according to the most important diagnostic signs, first and foremost, to the number of gill stamens and some plastic signs, Caspian anadromous shad from the Akhtuba River falls within the range of the diversity that is typical for the form.