Elmer R. Noble

Parasites and Fishes in a Deep-Sea Environment

Publisher Summary This chapter focuses on the animal parasites of fishes and presents a few examples of fishes and their parasites from the inshore and offshore epipelagic zone. These examples, ranging from tide pool species to cod that move from offshore shallow water to the mesopelagic zone, show that fishes in these habitats harbor many kinds of parasites, often in large numbers. In the deep marine environments, the chapter focuses on the benthopelagic and benthic habitats and on a comparison between them and the strikingly different midwater zones. The chapter provides an ecological discussion of parasite–host relationships in marine fishes. It discusses environmental factors that influence the variety of parasites and incidences of infection in deep-sea animals. It lists the characteristics of deep ocean waters––namely, (1) physical features, (2) plankton and the food supply, and (3) metabolism in the deep sea. These characteristics are the chief factors that determine the kinds, numbers, and behavior of the organisms living in these waters. Differences in parasite patterns between two groups of fishes are correlated with differences in food and migratory habits, life histories, body size, length of life, physical environmental features, and energy relationships.

Seasonal variations in host-parasite relations between fish and their protozoa

From July 1955 to June 1956 a study of host-parasite relations between three species of marine fish and their Protozoa was made at Plymouth. Callionymus lyra, a bottom-dweller, tends to be more abundant during the summer months, consumes a wide variety of food, and was more heavily infected with Protozoa than were the other two species offish. Gadus merlangus is an active predator, feeding on small fish, and although it has about the same numbers of kinds of Protozoa as does C. lyra , it was less heavily parasitized. G. merlangus , however, was more heavily parasitized with worms than were the other two fish. Microstomus kitt is a sluggish bottom-dweller, feeding on annelids, and, although over 99% were infected with myxosporidia, the intensity of infection was generally low. Very few other parasites were found in M. kitt . An active predatory habit combined with a taste for a wide variety of food appears to predispose to heavy parasitism. Some evidence for seasonal variations in intensities of protozoan infection in Callionymus lyra was obtained, but for conclusive results more precise methods of measuring numbers of parasites, and further studies carried on over a period of at least three consecutive years, must be made. The report is presented primarily to emphasize the importance of an ecological approach to the study of parasitology.

A groundwater hypothesis for the origin of “fire areas” on the Northern Channel Islands, California

Abstract Pleistocene areas of red sediments and carbonized vegetation on the Northern Channel Islands, California, have in the past been interpreted as caused by fires of either natural or human origin. Some are associated with darkened mammoth and bird fossils, and these fossils have been considered as having been burned by early man. Reevaluation of these so-called “fire areas” indicates that the above phenomena are the result of low-temperature (≤100°C), nonheating processes occurring in groundwater. Evidence for this conclusion is derived from field observations on fossil carbonized vegetation, and the geology of the areas. Additional evidence derives from experiments on the red sediments and fossil wood, X-ray diffraction analyses, magnetic analyses, studies on the clay minerals smectite and illite, and the demonstration that fossil mammoth bone contains sufficient Fe and Mn to account for their discoloration. Much of the carbonization of vegetation probably occurred in water rather than in fire. Radiocarbon dates from the islands will probably need to be reevaluated. These data provide evidence contrary to the concept of the occurrence of significant fires, either natural or set by early man, on the Northern Channel Islands.

Myxosporida of Macrourid Fishes from Southern California and Mexico

Three species of macrourids yielded the following myxosporidans. From Coryphaenoides acrolepis (Bean) we recovered Ceratomyxa hokarari Meglitsch and Leptotheca informis Auerbach from the gall bladder; and Davisia coryphaenoidia sp. n., Myxoproteus californicus sp. n., and Sinuolinea magna sp. n. from the urinary bladder. The kidney of Coelorhynchus scaphopsis (Gilbert) was infected with Myxobolus mexicanus sp. n., and its gall bladder with Leptotheca informis. The gall bladder of Nezumia stelgidolepis (Gilbert) was infected with Myxidium coryphaenoidium Noble and a species of Ceratomyxa. Of the macrourid fishes studied to date, C. acrolepis possesses the richest fauna of myxosporidan parasites. The highest incidence of infection for this host was by C. hokarari (52% of 52 hosts), and the lowest incidence was by S. magna (6% of 17 hosts). Brief comments on multiple infections, parasite distribution, and host specificity are included. Little information is available concerning the role of parasitism in the biological organization of the deep ocean. This situation has largely been due to technical difficulties in obtaining suitable hosts from deep waters, and to inadequate numbers of parasitologists working in this area of research (Noble, 1973). We are presently engaged in an extensive study of animal parasites infecting fishes of the family Macrouridae, in hopes of gaining some understanding of the ecology of parasite-host relationships in a deep-sea environment. This paper deals specifically with the myxosporidan parasites inhabiting macrourids from waters off southern California and Baja California, Mexico. A study of Myxosporida from macrourid fishes of the North Atlantic, including a note on all previous reports of these parasites from macrourids, was made by Yoshino and Noble (1973). MATERIALS AND METHODS Collection data and autopsy dates are summarized in Table I. All autopsies were performed on specimens that had been fixed in formalin and preserved in alcohol, with the exception of Coryphaenoides acrolepis collected in April 1972, in which freshly extracted internal organs were fixed in alcohol-formalin-acetic acid and later transferred to 50% ethanol. Urinary bladders were found in only 17 of the 52 C. acrolepis examined in the present study. Removal of the gonads and urinary bladders by another investigaReceived for publication 13 March 1973. * This study was supported by NSF Grant GA 34144. tor, and the eating of these organs by sea birds before the fish could be recovered from freevehicle set lines, were the primary reasons for the absence of urinary bladders. Detailed examinations of the Myxosporida from these fishes were performed at the University of California, Santa Barbara, as described in Yoshino and Noble (1973). Dimensions of Myxosporida are given in microns.

Three genera of Myxosporida (Protozoa) in macrourid fishes.

Abstract Three genera and eight species, three new, of myxosporida were recovered from seven genera and twenty species of geographically dispersed macrourid fishes. The constancy in spore dimensions of these species over large distances and among many host species was remarkable. Two genera of myxosporida had species which dwelled in both the gall bladder and urinary bladder/kidney.

Fossil mammoths from Santa Cruz Island, California

Abstract Mammoth remains on Santa Cruz Island, one of the four Northern Channel Islands of California, are very sparse, in marked contrast to those reported from Santa Rosa and San Miguel Islands of the same island group. A probable major reason for this scarcity is that Quaternary deposits are greatly restricted on Santa Cruz Island. It is proposed, contrary to popular opinion, that fossils found on Santa Cruz Island were derived from animals which died on the island, and were not transported there by humans. Reasons for this conclusion are that the size and geological context of the fossils are similar to those of the largest mammoth fossils of Santa Rosa Island, and that, in spite of extensive investigations by many persons, mammoth remains have not been found in middens, either on the islands or on the adjacent mainland.

The Flagellate Cryptobia in Two Species of Deepsea Fishes from the Eastern Pacific

Since 1888, eight species of Cryptobia (= Trypanoplasma) have been described or mentioned from marine fishes. The present paper describes two new species: C. stilbia, from the stomach of Bathylagus stilbius, a mesopelagic fish from the coast of California, and C. coryphaenoideana from the stomach of Coryphaenoides acrolepis, a bathypelagic fish from the coasts of Mexico and California. Transmission of the parasites is probably accomplished by direct transfer from the stomach of the host through the mouth and into water swallowed by another fish. The biology of the host fish is briefly discussed. During a study of parasitism in deepsea fishes from the coasts of California and Mexico, I found protozoan flagellates belonging to the family Cryptobiidae in the stomachs of the deepsea smelt, Bathylagus stilbius, a mesopelagic species collected from depths to about 750 m, and the macrourid, Coryphaenoides acrolepis, a bathypelagic species taken at 900 to about 2,500 m. These flagellates have not previously been reported from deepsea fishes. Approximately 45 species of cryptobiids have been described or mentioned in the literature, including eight from marine fishes, 24 from freshwater fishes, two free living, and one each from salamanders, a frog, heteropod, planarian, siphonophore, chaetognaths, leech, mole cricket (Gryllotalpa), lizard and two or three from snails. Most of the above species of flagellates are poorly described, and the validity of some of them is questionable. The eight species from marine fishes are as follows: (1) Cryptobia dahli (Mibius, 1888) Alexeieff, 1912, from the esophagus and stomach of Cyclopterus lumpus collected near Bergen, Norway. (2) Trypanoplasma intestinalis Leger, 1905, from the esophagus and stomach of Box boops in the Mediterranean. Martin (1914) observed three anterior flagella in this species, and consequently he changed the name to Trypanoplasmoides intestinalis. (3) Trypanoplasma congeri Elmhirst and Martin, 1910, from the stomach of Conger niger at Millport, Scotland. (4) Cryptobia trematomi Woodcock and Lodge, 1921, from the stomach and ascending intestine of Received for publication 8 December 1967. * Supported by NSF G.B. 6356 and NSF G.B. 4669. Trematomus bernacchii from waters off Cape Evans and Cape Adare, in the Antarctic region. (5) Trypanoplasma parmae Mackerras and Mackerras, 1925, from the blood of Parma microlepis collected near Sydney, New South Wales. These authors stated in 1961 that in their original preparations the blood may have been contaminated with fluid from the esophagus of the host. The site of infection is therefore in doubt. (6) Trypanoplasma flesi Nowicki, 1940, from the blood of Pleuronectes flessus, was mentioned as often occurring in the host, but it was never described. It therefore should be considered a nomen nudum. (7) Trypanoplasma makeevi Achmerov, 1959, from the blood and spleen of salmon, Onchorhynchus gorbuscha and 0. keta, collected at the mouth of the Amur River, Russia. The parasites were presumably of marine origin. (8) Cryptobia bullocki Strout, 1965, from the blood of Pseudopleuronectes americanus, Liopsetta putnami, Fundulus heteroclitus, and F. maialis collected from the coast of northern New England, USA. The most recent discussion of the problem of generic designation of these flagellates is that of Strout (1965). Like others before him, Strout concluded that until more information about the parasites is known a single genus should be retained. I agree with this conclusion. Cryptobia Leidy, 1846, described from the seminal vesicles of a snail, has priority over Trypanoplasma Laveran and Mesnil, 1909, described from the blood of a freshwater fish. MATERIALS AND METHODS Specimens of Bathylagus stilbius (Gilbert) (Family Bathylagidae) were collected with an Isaacs-Kidd midwater trawl and examinations made of living material on board ship. The area

Zschokkella (Protozoa: Myxosporida) in macrourid fishes

Abstract Six species of Zschokkella, three new, were recovered from eleven genera and forty-three species of macrourid fishes found in both the Atlantic and Pacific Oceans and many adjacent seas. The constancy in spore size and shape, over great distances and among many hosts, was remarkable.

Parasitism in the bathypelagic fish, Melanostigma pammelas

Abstract Three hundred and thirty-seven specimens of the zoarcid fish, Melanostigma pammelas, collected between December, 1950 and December, 1969 from bathypelagic waters off southern California, were examined for their parasites. Incidences of infection were: digentic Trematoda 61%, Myxosporida 39%, larval Nematoda 9%. Two adult trematodes are described: Fellodistomum melanostigmum nov. sp. from the intestine, and Aponurus pacificus nov. sp. from the stomach. This parasite record is markedly unlike the typical record reported for eastern Pacific mesopelagic fishes in which many larval nematodes and few, if any, adult trematodes were found. Our long-term objective is to explain parasite pattern differences in the deep ocean in terms of their biological and physical environments. Our initial purpose is to determine the numbers and kinds of parasites in M. pammelas.

A NEW PHILICHTHYID COPEPOD PARASITIC IN THE MUCOUS CANALS OF SURFPERCHES (EMBIOTOCIDAE)

Eighty-one of 324 marine fishes (11 genera, 16 species) were found to be infested with the copepod, Colobomatus embiotocae sp. n. The parasites live beneath the skin covering the bony ridges of the head, and in the cephalic sensory canal system. Fishes were collected from the coasts of Oregon, California, and Mexico. The type host is Cymatogaster aggregata Gibbons. Female copepods average 3.73 mm long, with 11 body segments (4th and 5th fused). The portion of the body anterior to the genital segment has distinct constrictions and is not fusiform. Ends of all body lobes are covered with minute spinules. The first antennae average 92 , in length. Thoracic lobes are single, not bifurcated. Each furca has a sharp spine on the inside lateral surface. The egg-laying apparatus has a bulblike structure equipped with a flagellate seta. Male copepods average 1.18 mm long, with 11 body segments. The first and second antennae are each composed of 6 segments; mandibles of 1 segment. Maxillae are biramous. Each caudal furca consists of a single segment with 6 setae. The frequency distribution of number of female copepods per host shows a repulsed distribution which deviates from expected Poisson frequencies. Analysis of variance shows that the lengths of female copepods from different host species and from different sampling areas are significantly different. There is no correlation between lengths of female Colobomatus and lengths of their hosts.