Two New Species of Cestoda from California Rays

Abstract

Acanthobothrium olseni sp. n. (Tetraphyllidea: Oncobothriidae), characterized by number of testes and segments, size of hooks, cirrus sac, and ovary, was found in two of four shovelnose guitarfish from Newport Beach, California. Discobothrium myliobatidis sp. n. (Lecanicephalidae) is characterized by number of testes, length and shape of strobila, and distribution of vitellaria. It was found in one of three bat stingrays from Long Beach, California. The genus Discobothrium is discussed. From November 1966 through May 1968 150 elasmobranchs, representing five families of rays and 11 families of sharks, were examined for helminth parasites. This report is the first in a series on the findings of this survey. Specimens were removed from the spiral valve of the hosts, fixed in AFA, stained in Semichon's carmine, dehydrated in ethanol, cleared in xylene, and mounted in Piccolyte. Drawings were made with the aid of a drawing tube. All measurements are in microns unless otherwise stated. Average measurements are given with ranges in parentheses. Acanthobothrium olseni sp. n. (Figs. 1-4) The following description is based on 16 specimens found in the spiral valves of two shovelnose guitarfish, Rhinobatos productus Ayres, 1854 from Newport Beach, California. The species is named in honor of Dr. 0. Wilford Olsen.