Physalopteroides bahamensis n. sp. (Nematoda: Spiruroidea) from the Cuban Treefrog Osteopilus septentrionalis (Hylidae) from San Salvador Island, Bahamas

Abstract

Four hundred eighty-six specimens of Physalopteroides bahamensis n. sp. (Nematoda: Spiruroidea: Physalopteridae) were recovered from the gastrointestinal tracts of 61 of 72 preserved specimens of the Cuban treefrog, Osteopilus septentrionalis. Prevalence of infection was 85% and mean intensity was 8.4. Physalopteroides bahamensis belongs to the group of Physalopteroides species with a smooth left lip. The new species also is distinguished by number of teeth on the right lip, symmetrical caudal alae, unequal spicules, and arrangement of caudal papillae. These nematodes represent the third known species of Physalopteroides from the Western Hemisphere and the first report of the genus from the Bahamas. Wu & Liu (1940) erected the genus Physalopteroides to accept a new nematode species recovered from the Asian long-nosed tree snake, Ahaetulla (=Dryophis) prasinus (Reinwardt, 1827), from Kwangsi, China. The generic diagnosis included the possession of teeth on the right lip only. This description was modified by Chabaud & Brygoo (1960) to include all species with dentation limited to one lip, and six species were transferred from the genus Thubunaea. There are currently 15 described species of Physalopteroides, six from the Ethiopian Realm, six from the Oriental Realm, one from the Australian Realm, one from the Neotropical Realm, and one from the Nearctic Realm (see Baker, 1987; Elwasila, 1990). Physalopteroides bahamensis n. sp. is the second species described from the Nearctic Realm. The Cuban treefrog, Osteopilus septentrionalis Dumeril & Bibron, 1841 is known from Cuba, Island de Pinos, the Bahamas, and the Cayman Islands and has been introduced in Puerto Rico, St. Croix, South Florida, and the Florida Keys (Schwartz & Henderson, 1991). The species is widespread but occurs primarily in mesic habitats. On San Salvador Island, Bahamas, it is sympatric with the frog Eleutherodactylus planirostris Cope, 1863 and the lizards Anolis distichus Cope, 1862, A. sagrei Drumeril & Bibron, 1837, Cyclura rileyi Stejneger, 1903, Leiocephalus loxogrammus Cope, 1887, and Sphaerodactylus corticola Garman, 1888. 0. septentrionalis was reported to harbor at least 11 species of nematodes (see Coy Otero & Ventosa, 1984). The purpose of this 1 We thank Peggy Firth for the preparation of the illustrations constituting Figs. 1-7. This investigation was part of Research Project Number B-154, Bahamian Field Station, San Salvador Island, Bahamas. We are indebted to the Bahamian Field Station and its staff on San Salvador Island, Bahamas for logistical support of this project. TRANS. AM. MICROSC. Soc., 113(2): 169-176. 1994. ? Copyright, 1994, by the American Microscopical Society, Inc. This content downloaded from 157.55.39.127 on Wed, 29 Jun 2016 04:32:36 UTC All use subject to http://about.jstor.org/terms TRANS. AM. MICROSC. SOC. note is to describe Physalopteroides bahamensis n. sp. taken from the gastrointestinal tract of 0. septentrionalis from San Salvador Island, Bahamas. MATERIALS AND METHODS Seventy-two 0. septentrionalis, mean snout-vent length (SVL) 48.2 mm (range 41-66), were hand-collected and fixed in 10% formalin at the Bahamian Field Station (24?07'N, 74?28'W; 0 m elevation), San Salvador Island, Bahamas, 7-10 June 1991. The abdominal wall was slit to allow rapid penetration of fixative into the internal organs. Male frogs were more abundant (n = 63) and smaller (mean SVL = 46.5 mm; range, 41-53 mm) than female frogs (n = 9; mean SVL = 60.1; range, 52-66 mm). Specimens were deposited in the herpetology collection of the Natural History Museum of Los Angeles County (LACM 139733-139804). The body cavity was opened by a longitudinal incision from throat to vent and the gastrointestinal tract was removed by cutting across the esophagus and the rectum. The esophagus, stomach, small intestine, and large intestine were examined separately under a dissection microscope. Each nematode was examined utilizing a glycerol wet-mount procedure. Selected specimens were stained with iodine. Measurements are given in mm unless otherwise noted.