A taxonomic guide to the mysids of the South Atlantic Bight.

Following the examination of extensive collections from the National Museum of Natural History (NMNH), the Southeastern Regional Taxonomic Center (SERTC), and other regional institutions, 18 species of the family Mysidae are recognized and described from the South Atlantic Bight (Cape Lookout, North Carolina to Cape Canaveral, Florida). This report includes synonymies of previous records, as well as new species distribution records. Previous regional accounts of Metamysidopsis munda and Metamysidopsis mexicana are attributed to Metamysidopsis swifti. New regional records are established for Amathimysis brattegardi, Heteromysis beetoni, and Siriella thompsonii. Two other species tentatively identified as Amathimysis sp. (nr. serrata) and Mysidopsis sp. (cf. mortenseni) may represent new taxa. Neobathymysis renoculata is included and discussed as a potential regional species. An illustrated key to the species currently known from the South Atlantic Bight is presented. Relevant taxonomic, distributional, and ecological information is also included for each species. (PDF file contains 45 pages.)

Note préliminaire sur quatre espèces nouvelles d'Hapalocarcinidae, avec quelques remarques au sujet du Cryptochirus rugosus Edmonson

This note briefly describes four new species of Hapalocarcinidae: Cryptochirus tri, Troglocarcinus edmonsoni, Troglocarcinus sheni, Troglocarcinus stimpsoni

On four species of Copepoda new to Chesapeake Bay, with a description of a new variety of Paracalanus crassirostris Dahl

At this time, four additional species, unreported by Wilson [1932], can be added to the list of those species to be found within the limits of the bay. These are Acartia tonsa Dana, Cyclops vernalis Fischer, Diaptomus spatulocrenatus Pearse, and Paracalanus crassirostris Dahl var. nudus nov. The specimens from which identifications were made were collected by means of Clarke-Bumpus nets, in use on the motor ship "Mahatru."

Report on fresh-water copepoda from Panama, with descriptions of new species

These collections were made by Meek and Hildebrand, in connection with their work on fishes in the seasons of 1911 and 1912, by Goldman in 1912, and by Marsh who was present in Panama for four weeks in 1912 for the express purpose of making such collections. Most of the collections were made within the limits of the Canal Zone. A few collections were made in eastern Colombia, some on Rio Bayana and its tributaries, some on the Chagres and Trinidad outside the Zone and some in the neighborhood of Chorrera and of old Panama... (Document has 33 pages)

Effects of some environmental factors on the fecundity of Tilapia species (Family Cichlidae) in Kigera Reservoir, New Bussa

The effects of some environmental factors on the fecundity of Tilapia species (Family Cichilidae) was carried out at the Kigera dam. Four Tilapia species caught were Tilapia zilli, Hemichromis fasciatus, Sarotherodon galilaeus and Oreochromis niloticus while the environmental factors considered were water temperature, Dissolved Oxygen, pH value, level of rainfall and rate of sunshine and range of time. 43 fish comprising of 25 male with (58.1%) and 18 females having (41.9%) were studied with 74.42% been sexually matured. Both high levels of rainfall and dissolved oxygen favoured fecundity. The spawning peak occurred in (July), environmental factors monitored indicated that dissolved oxygen ranges from 3.7 to 4.45mg/lit rainfall ranges from (34.90mm to 237.80mm) sunshine ranges from (5hrs-8hrs) and pH ranges from (7.35-7.45). The spawning of these species in their natural or hatchery condition is therefore best achieved during the peak of raining season

Ecological aspects of New Forest streams, draining one of Britain's unique areas

This article describes the streams of this unique area of Britain and reviews the published and some unpublished information that is currently available. None of the rivers in the New Forest are more than 30 km long. Many reaches have been artificially straightened, channelized and regraded since the 1840's. The stream waters are typically base-poor, with low nutrient concentrations. Primary productivity and standing crops of algae are predictably low when compared with other streams carrying higher concentrations of minerals and nutrients. The earliest records on the macroinvertebrate fauna go back to the late 19th Century. By 1940, over 20 species of Trichoptera and 10 species of Plecoptera had been recorded, but only four species of Ephemeroptera. Twenty species of fish occur in the streams of the New Forest of which the most common are brown trout, minnow, bullhead, stone loach, brook lamprey and eel.

Diversity of estuarine movements of striped bass (Morone saxatilis): a synoptic examination of an estuarine system in southern New Jersey

We determined the dis-tribution of multiple (n=68; 508−978 mm total length [TL]) striped bass (Morone saxatilis) along the estua-rine salinity gradient in the Mullica River−Great Bay in southern New Jersey over two years to determine the diversity of habitat use and the movements of striped bass. Ultrasoni-cally tagged fish were detected in this estuarine area by means of wireless hydrophones deployed at four gates inside the entrance of the study area and farther up to tidal freshwater (38 km). Numerous individuals frequently departed and returned to the estuary, primarily in the spring and late fall over periods of 15−731 days at liberty. The period of residency and degree of movement of individuals to and from the estuary varied extensively among seasons and years. The diversity of movements in and out of, as well as within, the estuary differed from the less-complex patterns reported in earlier studies, perhaps because of the comprehensive and synoptic nature of this study.

Bathyraja panthera, a new species of skate (Rajidae: Arhynchobatinae) from the western Aleutian Islands, and resurrection of the subgenus Arctoraja Ishiyama

We provide morphological and molecular evidence to recognize a new species of skate from the North Pacific, Bathyraja panthera. We also resurrect the skate subgenus Arctoraja Ishiyama, confirming its monophyly and the validity of the subgenus. Arctoraja was previously recognized as a distinct subgenus of Breviraja and later synonymized with Bathyraja (family Rajidae). Although the nominal species of Arctoraja have all been considered synonyms of Bathyraja parmifera by various authors, on the basis of morphometric, meristic, chondrological, and molecular data we recognize four species, including the new species. Species of Arctoraja are distributed across the North Pacific Ocean and adjacent seas from southern Japan to British Columbia. Bathyraja parmifera is abundant in the eastern Bering Sea, Aleutian Islands, and northern Gulf of Alaska; B. smirnovi is a western Pacific species found in the Sea of Okhotsk and Sea of Japan; B. simoterus is restricted to waters around the northern and eastern coasts of Hokkaido, Japan; and the new species B. panthera is restricted to the western Aleutian Islands. Bathyraja panthera is diagnosed by its color pattern of light yellow blotches with black spotting on a greenish brown background, high thorn and vertebral counts, chondrological characters of the neurocranium and clasper, and a unique nucleotide sequence within the mitochondrial cytochrome oxidase gene. Furthermore, the species presently recognized as Bathyraja parmifera exhibits two haplotypes among specimens from Alaska, suggesting the possibility of a second, cryptic species.

Quantitative determination of the timing of otolith ring formation from marginal increments in four marine teleost species from northwestern Australia

The sectioned otoliths of four fish species from a tropical demersal trawl fishery in Western Australia revealed a series of alternating trans-lucent and opaque zones in reflected light. The translucent zones, referred to as growth rings, were counted to determine fish ages. The width of the opaque zone on the periphery of the otolith section as a proportion of the width of the previous opaque zone (index of completion) was used to determine the periodicity of growth-ring formation. This article describes a method for modeling changes in the index of ring completion over time, from which a parameter for the most probable time of growth-ring formation (with confidence intervals) can be determined. The parameter estimate for the timing of new growth-ring formation for Lethrinus sp. 3 was from mid July to mid September, for Lutjanus vitta from early July to the end of August, for Nemipterus furcosus from mid July to late September, and for Lutjanus sebae from mid July to mid November. The confidence intervals for the timing of formation of growth rings was variable between species, being smallest for L. vitta, and variable between fish of the same species with different numbers of growth rings. The stock assessments of these commercially important species relies on aging information for all the age classes used in the assessment. This study demonstrated that growth rings on sectioned otoliths were laid down annually, irrespective of the number of growth rings, and also demonstrated that the timing of ring formation for these tropical species can be determined quantitatively (with confidence intervals.

Differences in diet of Atlantic bluefin tuna (Thunnus thynnus) at five seasonal feeding grounds on the New England continental shelf

The stomachs of 819 Atlantic bluefin tuna (Thunnus thynnus) sampled from 1988 to 1992 were analyzed to compare dietary differences among five feeding grounds on the New England continental shelf (Jeffreys Ledge, Stellwagen Bank, Cape Cod Bay, Great South Channel, and South of Martha’s Vineyard) where a majority of the U.S. Atlantic commercial catch occurs. Spatial variation in prey was expected to be a primary influence on bluefin tuna distribution during seasonal feeding migrations. Sand lance (Ammodytes spp.), Atlantic herring (Clupea harengus), Atlantic mackerel (Scomber scombrus), squid (Cephalopoda), and bluefish (Pomatomus saltatrix) were the top prey in terms of frequency of occurrence and percent prey weight for all areas combined. Prey composition was uncorrelated between study areas, with the exception of a significant association between Stellwagen Bank and Great South Channel, where sand lance and Atlantic herring occurred most frequently. Mean stomach-contents biomass varied significantly for all study areas, except for Great South Channel and Cape Cod Bay. Jeffreys Ledge had the highest mean stomach-contents biomass (2.0 kg) among the four Gulf of Maine areas and Cape Cod Bay had the lowest (0.4 kg). Diet at four of the five areas was dominated by one or two small pelagic prey and several other pelagic prey made minor contributions. In contrast, half of the prey species found in the Cape Cod Bay diet were demersal species, including the frequent occurrence of the sessile fig sponge (Suberites ficus). Prey size selection was consistent over a wide range of bluefin length. Age 2–4 sand lance and Atlantic herring and age 0–1 squid and Atlantic mackerel were common prey for all sizes of bluefin tuna. This is the first study to compare diet composition of western Atlantic bluefin tuna among discrete feeding grounds during their seasonal migration to the New England continental shelf and to evaluate predator-prey size relationships. Previous studies have not found a common occurrence of demersal species or a pre-dominance of Atlantic herring in the diet of bluefin tuna.

A new deep-sea crab, genus Chaceon, from the Arabian Sea (Crustacea, Decapoda, Geryonidae)

The sixth nominal species of Chaceon to be recorded from the western Indian Ocean is named from a specimen collected off Somalia in 504-506 meters. Chaceon somaliensis, n. sp., resembles C. macphersoni (Manning and Holthuis, 1988) and differs from the other four species known from the area in having the dactylus of the walking legs dorsoventrally depressed. It differs from C. macphersoni in having slenderer legs, a smoother body, and a much deeper, evenly curved orbit.

Two new species and two new reports of Ulva L. (Ulvophyceae) from the coast of Karachi, Pakistan

Morphology and taxonomy of four species of Ulva i.e. U. anandii Amjad et Shameel sp. nov., U. bifrons Ardre, U. saifullahii Amjad et Shameel sp. nov. and U. taeniata (Setchell) et Gardner were described for the first time from Pakistan. Their anatomy has been investigated in detail and compared with the allied species. A taxonomic comment has been written on U. grandis Saifullah et Nizamuddin.

Acyclic diterpene alcohols isolated from four algae of Bryopsidophyceae and their toxicity

Three new acylic diterpenoids belonging to the class of phytol series have been isolated. They were obtained from the ethyl acetate soluble fractions of four siphonaceous green seaweeds, Bryopsis pennata Lamour., Caulerpa taxifolia (Vahl) C. Ag., Codium decorticatum (Woodw.) Howe and Valoniopsis pachynema (Mart.) Børg., collected from Karachi coast of Pakistan. Structures of these compounds were elucidated with the help of spectroscopic methods and confirmed by comparison with the known compounds. Even the known compounds are being reported for the first time from a green algal source. All the compounds were found to display a strong toxicity at all the three concentrations tested in the brine shrimp bioassay.

On the comparative fishing experiments with a four-seam and a two-seam trawls on the east coast

Fishing experiments were undertaken to study the relative utility of a newly designed four seam type net on a conventional two seam net at the centre along the East Coast in both inshore and deeper zones (up to 100m.) and the results indicated that the new four seam net has given higher catch rate of 6 to 8% more with higher catch rate of fish supposed to belong to off bottom region. Further this gear found more selective in obtaining Lactarius, which is one of the good variety of fish from trawlers, in both quantity as well as in quality. In terms of horizontal spread this new net gave less on comparison with the conventional two seam net, thereby showed corresponding increase in vertical spread; but warp tension remained more or less same in both the gear. Both gear have worked equally well in majority of depth ranges experimented with optimum spread. Finally the results indicated that the new net can work well from the present trawlers along the coast.