New Species of Onchocercidae (Nematoda: Filarioidea) from Pica pica hudsonia (Sabine, 1823)

Abstract

The following new species of Onchocercidae (Nematoda: Filarioidea) are described from the American black-billed magpie, Pica pica hudsonia (Sabine, 1823): Splendidofilaria picacardina, from the myocardium directly behind the aortic and pulmonary semilunar valves; Splendidofilaria caperata, from the walls of the pulmonary arteries; Chandlerella striatospicula, from the connective tissue around the splenic artery, esophagus, or in the mesenteries; and Eufilaria longicaudata, from the connective tissue around the esophagus. Microfilariae of all species occur in the blood. No species of Onchocercidae have been described from American black-billed magpies, but there are several reports of microfilariae found during surveys for protozoan blood parasites. Coatney and Roudabush (1937) reported microfilariae in magpies during an examination of birds in Nebraska. In a later study of birds in Montana, Coatney and Jellison (1940) noted two types of microfilariae in magpies. Wagner (1947) reported that 17 of 48 magpies examined in eastern Washington had microfilariae. Hagen and Olsen (1957) found that 62 of 200 magpies in northern Colorado had microfilariae. During a recent survey in central Colorado, Stabler (1961) observed microfilariae in as many as 78.5% of the magpies. This report describes the species found in magpies in northern Colorado. MATERIALS AND METHODS The adult nematodes were obtained during the examination of 143 magpies. All measurements were based on 25 nematodes selected at random from specimens fixed in hot 70% alcohol and cleared in glycerin. Microfilariae were identified by dissection of specimens from living female worms. The presence or absence of a sheath was determined by study of live microfilariae with the aid of a phase-contrast microscope. All measurements were based on 25 specimens selected at random from slides stained with hematoxylin and eosin. The slides were prepared from blood obtained from lungs of heavily infected birds. Measurements are in microns unless otherwise indicated. Splendidofilaria picacardina sp. n. (Figs. 1-9) Description Filarioidea; Onchocercidae (Leiper, 1911) Chabaud and Anderson, 1959; Splendidofilariinae Chabaud and Choquet, 1953; Splendidofilaria Skrjabin, 1923. Slender worms with attenuated extremities. Cuticle thin, with minute, regular annulations and transverse striations. Cuticle with transversely elongated bosses irregularly distributed around the body except at the extremities (Figs. 1, 2). Cephalic extremity with four submedian papillae and two minute amphids (Fig. 5). Buccal capsule absent. Excretory pore not seen. Esophagus long, slender, without evidence of muscular or glandular tissue (Fig. 1). Intestine broad. Caudal extremity usually bears small, lateral protuberances (Figs. 8, 9). Male (Figs. 3, 6, 7, 8) Length 15 (11 to 20) mm, width 112 (95 to 130). Nerve ring 92 (85 to 100) from anterior end of body. Esophagus 450 (430 to 485) long, 6 (4 to 10) wide. Cloaca 76 (62 to 89) from posterior end of body. Caudal extremity blunt, with two pairs precloacal papillae and two pairs postcloacal papillae; some have only seven papillae (Figs. 3, 7). Spicules subequal, dissimilar; left 60 (50 to 65) long, terminating in a point; right 46 Received for publication 22 April 1964. * A portion of a dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Zoology, Colorado State University, Fort Collins, Colorado. This work was done while the author was the recipient of a Dow Chemical Research Fellowship from the Dow Chemical Company, Midland, Michigan. t Present address: USDA, ARS, ADP, P.O. Box 518, University Park, New Mexico.