A Survey of the Blood Parasites of the Marine Fishes of Puerto Rico

Abstract

Heart or arterial blood smears were made from 1,340 marine fishes of 126 species, collected from the coastal waters of Puerto Rico. The only blood parasites found were haemogregarines. Haemogregarina bigemina was present in 11 fishes belonging to the following eight genera: Hemiramphus brasiliensis (Linnaeus), Lutjanus apodus (Walbaum), Ocyurus chrysurus (Bloch), Caranx bartholomaei Cuvier, C. hippos (Linnaeus), Haemulon aurolineatum Cuvier, Scarus croicensis (Bloch), Sparisoma aurofrenatum (Valenciennes), and Auxis thazard (Lacepede). All except Lutjanus apodus, Ocyurus chrysurus, and Caranx hippos are believed to be new records of infection by any haemogregarine. Haemogregarines (Protozoa: Sporozoa: Coccidia: Adeleidae) are the most common blood parasites found in marine fishes. None of their vectors is known and, therefore, as yet no complete life history of them has been worked out. The effect they may have upon the health of fishes, and whether or not they may be a factor in the periodic disappearance of commercially important species from a given area, are also unknown. The first haemogregarines of marine fishes in North America were reported from eastern Canada by Fantham et al. (1942). Laird (1961) also described a new species, Haemogregarina irkalukpiki, from northern Canada in the sea-run arctic char, Salvelinus alpinus. Saunders (1955, 1958, 1959, 1960, 1964) has described the presence of H. bigemina, and several new species of this genus, from the marine fishes of Florida, Bermuda, Bimini in the Bahamas, and the Red Sea. This paper gives the results of a general survey of the blood parasites of marine fishes from the coastal waters of Puerto Rico. As has been the case with a number of similar surveys elsewhere, only haemogregarines were encountered. The incidence of infection among the Puerto Rican fishes was very light, as has been true in every area the author has studied except the Red Sea (1960). It was hoped that in the Puerto Rican material one or more host species would be found which had a high enough incidence of parasitism by haemogregarines to make possible future experiments upon their vectors and methods of transmission. MATERIALS AND METHODS As is shown in Table I, 1,340 fishes of 126 species, belonging to 47 families and 12 orders, were examined for blood parasites. They were collected from early January through late April; and from Montalva Bay near Guanica as the easternmost point, westward through the La Parguera area to Cabo Rojo, and northward from there along the western coastline of Puerto Rico at El Combate, Mayagiiez 1This research was supported by grant GB2699 from the National Science Foundation. The author's deep thanks for aid in the collecting and identification of fish species go to the Staff of the Institute of Marine Biology of the University of Puerto Rico at Mayagiiez, especially to former Director John E. Randall, Drs. Luis R. Almadovar and Gilbert W. Bane, and Mr. Jorge Rivera L6pez; also to Mr. Donald S. Erdman, Fishery Biologist under Federal Aid to Sport Fish Restoration F-I-R, Department of Agriculture, P.R.; and to Capt. Tom Gifford of the sport-fishing boat Princess Vista Mar of the Clay Jackson Enterprises of Loiza, P.R. Living quarters and laboratory facilities were made available at the field station of the Institute of Marine Biology of the University of Puerto Rico on Isla Magueyes near La Parguera. TRANS. AMER. MICROSC. Soc. 85(2): 193-199. 1966. This content downloaded from 157.55.39.104 on Mon, 20 Jun 2016 06:04:11 UTC All use subject to http://about.jstor.org/terms DOROTHY CHAPMAN SAUNDERS