A New Species of Lagenophrys (Ciliophora: Peritrichia) Symbiotic on Marine Amphipods

Abstract

Lagenophrys crutchfieldi n. sp., a loricate peritrich, is an ectocommensal on two species of the marine amphipod genus Parhyale and becomes one of the few species in its genus known to occur on marine hosts. Differences in the distribution of L. crutchfieldi on the bodies of its two hosts may be linked to a difference in the force of their respiratory currents, which carry food particles to the ciliates. L. crutchfieldi is one of a small group of species in its genus hosted by talitroid amphipods, but there is no indication that members of this group have a close phylogenetic relationship. The 54 species in the peritrich genus Lagenophrys live as ectocommensals on crustaceans in many types of habitats throughout the world (Clamp, 1991); however, only five of them occur on marine or estuarine hosts. Lagenophrys eupagurus Kellicott, 1893 and the closely related L. callinectes Couch, 1967 are found on marine and estuarine decapods (Clamp, 1989; Couch, 1967), but the former species also is widespread on freshwater decapods (Clamp, 1989). Both L. cochinensis Santhakumari, 1976 and L. limnoria Clamp, 1988 are symbionts of wood-boring isopods (Clamp, 1988a; Santhakumari, 1976; Santhakumari & Gopalan, 1980; Santhakumari & Nair, 1985). Lagenophrys tattersalli Willis, 1942 occurs on the gills of marine amphipods in Great Britain (Willis, 1942) and France (Clamp, unpublished observations). Also, Fenchel (1965) reported an undescribed species of Lagenophrys from marine amphipods collected in the coastal waters of Denmark. I have discovered and describe herein an additional marine species of Lagenophrys on two members of the amphipod genus Parhyale Stebbing, 1897, whose species are widely distributed in tropical and subtropical environments (Barnard, 1979; Shoemaker, 1956). MATERIALS AND METHODS Specimens of Parhyale hawaiensis (Dana, 1853) were collected with a dip net. They were fixed in Bouin's fluid for 24 h and transferred to 70% ethyl alcohol for preservation. Samples of L. crutchfieldi also were obtained from specimens of P. hawaiensis and P. penicillata Shoemaker, 1956 in the crustacean collection of the National Museum of Natural History, Smithsonian Institution (herein referred to as NMNH-CC). Permanent preparations were made by staining with Heidenhain's iron hematoxylin and protargol. Copper was omitted from the protargol solution. Some I I thank Dr. Austin B. Williams for arranging my visit to the crustacean collection of the National Museum of Natural History and Dave Penrose, who helped me collect amphipods on a memorable trip to Florida. Publication costs, in part, are being met by a grant from the Spencer-Tolles Fund of the American Microscopical Society. TRANS. AM. MICROSC. Soc., 112(1): 62-68. 1993. ? Copyright, 1993, by the American Microscopical Society, Inc. This content downloaded from 207.46.13.124 on Wed, 22 Jun 2016 05:21:34 UTC All use subject to http://about.jstor.org/terms VOL. 112, NO. 1, JANUARY 1993 ciliates were examined alive, but only fixed and stained material was used for drawings and measurements (see Clamp, 1990). Two samples of individuals stained with hematoxylin were measured with a filar micrometer. Only individuals oriented with their dorsal surface toward the observer and with their ventral surface parallel to the plane of the slide, or nearly so, were selected for measurement. Height of the lorica was measured by using the calibrated scale on the fine focusing knob of the microscope to determine the focal distance between the lorica's dorsal and ventral surfaces. Phase-contrast microscopy was used for this measurement because of the transparency of the lorica.