Life Sciences Commons^™

Evidence Of Spawning Capable Tarpon (Megalops Atlanticus) Off The Louisiana Coast, William Stein Iii, Nancy J. Brown-Peterson, James S. Franks, Martin T. O'Connell

Gulf and Caribbean Research

Despite the fact that the tarpon (Megalops atlanticus) is a popular sport fish in the Gulf of Mexico (GOM; Ault et al. 2008), little is known of its spawning behavior. Spawning M. atlanticus have never been documented and fertilized eggs have not been observed in situ (Ault et al. 2008). While it has been suggested that adult M. atlanticus move to deep water off the southwest coast of Florida and into the Yucatan Channel to spawn, the actual locations of spawning grounds remain unknown (Smith 1980, Crabtree et al. 1995, Crabtree et al. 1997). Distribution patterns of larvae …

Abundance And Distribution Of Two Species Of Squilla (Crustacea: Stomatopoda: Squillidae) In The Northern Gulf Of Mexico, Jennifer L. Wortham

Gulf and Caribbean Research

Stomatopods (mantis shrimps) are predatory benthic crustaceans. Mantis shrimp in the genus Squilla are frequent bycatch animals unintentionally collected in conjunction with the shrimp fishery in the Gulf of Mexico (GOM). Their carcasses are discarded instead of being retained for human consumption, fish meal, or other protein-based food products. The size, depth, salinity, and temperature distributions of these species, as well as their abundance based on gender, were examined to gain biological information that would be necessary if a fishery were to develop in the GOM. I collected samples (n = 2,854) of Squilla empusa and Squilla chydaea in the …

Morphological Characteristics Of Early Life History Stages Of The Blue Crab, Callinectes Sapidus Rathbun, From The Northern Gulf Of Mexico With A Comparison Of Studies From The Atlantic Seaboard, Kenneth Stuck, Harriet Perry, Darcie Graham, Richard W. Heard

Gulf and Caribbean Research

Zoeae, megalopae, and early crab stages of Callinectes sapidus Rathbun, 1896 were described from the northern Gulf of Mexico (nGOM). Observations during this study were based on larvae reared in the laboratory through the early crab stages and on megalopae and early crab stages collected in the wild. Gulf of Mexico data are compared with similar information for the southeast Atlantic coast of the United States. Size and setation of C. sapidus larvae reared from nGOM stocks were different than those in published descriptions of larvae reared from Atlantic populations. Seasonal differences in size were noted in both reared and …

Occurrence Of A Synchronous Hermaphroditic Striped Mullet, Mugil Cephalus, From The Northern Gulf Of Mexico, James S. Franks, Nancy J. Brown-Peterson, Dyan P. Wilson, Ronda J. Russell, Janaith K. Welker

Gulf and Caribbean Research

A synchronous hermaphroditic striped mullet, Mugil cephalus, was captured offshore of Southwest Pass, Louisiana on 6 December 1996 during the commercial roe mullet fishery harvest. The fish measured 412 mm FL, weighed 824 g and was determined to be 4 years old by otolith analysis. Gross examination of the gonads revealed four lobes: right and left ovaries and right and left testis which represents a unique occurrence among hermaphroditic fish. All lobes ended in a common sperm duct/oviduct with the exception of the left ovary which had no oviduct. Both ovaries contained vitellogenic oocytes and both testis had freely …

Cholangioma In A Wild-Caught Sheepshead Minnow (Cyprinodon Variegatus) From The Northern Gulf Of Mexico, Lee A. Courtney

Gulf and Caribbean Research

A single case of ac holangioma occurred in the liver of a wild-caught sheepshead minnow (Cyprinodon variegatus). This is the first biliary neoplasm and second case of a hepatic neoplasm reported from a wild-caught specimen of this species. The findings further demonstrate the susceptibility of the sheepshead minnow to neoplasm development and add support to its selection as a subject for field monitoring of carcinogenic exposure.

Trophic Structure Of Macrobenthic Communities In Northern Gulf Of Mexico Estuaries, Gary R. Gaston, Steven S. Brown, Chet F. Rakocinski, Richard W. Heard, J. Kevin Summers

Gulf and Caribbean Research

Trophic structure of estuarine benthic communities in the northern Gulf of Mexico was characterized according to the functional roles and geographic distributions of the macrobenthos. Macrobenthic organisms collected during two years of study were assigned to trophic groups to assess the relative utilization of detritus and other resources. Three groups of detritivores (surface-deposit feeders, subsurface-deposit feeders, and filter feeders) were numerically dominant among the benthos, each of which accounted for 25-30% of total abundance across regions. Carnivorous macrobenthos also comprised an appreciable portion (12%), while omnivores (<3%) and other groups (<4%) were poorly represented. Dominance by detritivores is consistent with current concepts regarding the role of macrobenthos in processing detritus of Gulf of Mexico estuaries.

Haustorius Jayneae, A New Species Of Haustoriid Amphipod From The Northern Gulf Of Mexico, With Notes On Its Ecology At Panama City Beach, Florida U.S.A., John M. Foster, Sara E. Lecroy

Gulf and Caribbean Research

A new species of sand-burrowing amphipod, Haustorius jayneae, is described from the swash zone and shallow subtidal sands along the north Florida and Mississippi Gulf coasts. It is most similar to H. canadensis from the American Atlantic coast, differing primarily in the presence of a distinct anterodistal spinous lobe on pereopod 6, article 5; a longer row of distal marginal spines on pereopod 7, article 4; and fewer proximal spines on the peduncle of uropod 1. A revised key to the known species of Haustorius is included and information on the ecology of H. jayneae n. sp. at Panama …

An Illustrated Key To The Chaetognatha Of The Northern Gulf Of Mexico With Notes On Their Distribution, Jerry A. Mclelland

Gulf and Caribbean Research

A key is provided to facilitate the identification of 24 species in nine genera of Chaetognatha occurring in the northem Gulf of Mexico. Included are the deep-water species, Eukrohnia proboscidea, E. calliops, Mesosagitta sibogae, and Sagitta megalophthalma, all recent additions to the known fauna of the region. Meristic data, brief descriptions, ecological notes, Gulf of Mexico records, and illustrations are also presented.

Acanthohaustorius Uncinus, A New Species Of Sand-Burrowing Amphipod From The Northern Gulf Of Mexico, With Notes On Its Ecology (Haustoriidae: Haustoriinae), John M. Foster

Gulf and Caribbean Research

A new species of sand-burrowing amphipod, Acanthohaustorius uncinus, is described from vegetated and unvegetated estuarine sands from St. Andrew Bay, Florida and East Ship Island, Mississippi. The genus Acanthohaustorius has been informally recorded from St. Andrew Bay, but this species is now formally described from the Gulf of Mexico. A. uncinus n. sp. is most similar to A. millsi of the Open American Atlantic coast. It differs from A. millsi in the presence of a dorsally directed, hooked spine on the peduncle of uropod 1 and the totally cleft telson lobes. Information on the ecology of A. uncinus n. …

Records Of Deep-Water Chaetognaths From The Northern Gulf Of Mexico, Jerry A. Mclelland, Harriet M. Perry

Gulf and Caribbean Research

Fourteen species of deep-water Chaetognatha were present in plankton samples collected between 200 and 677 m at five stations along the continental slope of the northem Gulf of Mexico. Samples were taken in conjunction with the MARFlN Geryon cruises of 1987 and 1988. New Gulf of Mexico records resulting from this study were Eukrohnia calliops, Eukrohnia proboscidea, Mesosagitta sibogae, and Sagitta megalophthalma. Other deepwater species present were Eukrohnia fowleri, E. bathypelagica, E. bathyantarctica, Caecosagitta macrocephala, Mesosagitta decipiens, M. minima, Solidosagitta planctonis, Krohnitta subtilis, Flaccisagitta hexaptera, and F. lyra …

An Unusually Small Egg-Carrying Callinectes Sapidus In The Northern Gulf Of Mexico, With Comments On The Barnacle Loxothylacus Texanus, Robin M. Overstreet, Harriet M. Perry, Gerald Adkins

Gulf and Caribbean Research

This communication reports the smallest verified egg-carrying specimen of Callinectes sapidus. With a carapace 20 mm long by 47 mm wide, the female measures considerably less than most other mature individuals, but about the same as an average-sized individual infected with an adult specimen of the rhizocephalan Loxothylacus texanus.

Notes On The Northern Gulf Of Mexico Occurrence Of Sagitta Friderici Ritter-Zahony (Chaetognatha), Jerry A. Mclelland

Gulf and Caribbean Research

The neritic chaetognath Sagitta friderici Ritter-Zahony, 1911 was identified in plankton samples from the northern Gulf of Mexico in June 1974. Specimens analyzed from two groups of adults ranged from 6 to 13.7 mm long. Meristic values did not appear to be a function of body length except for individuals in the 12.4 to 13.7 mm range that had larger numbers of hooks and teeth.

Adults of Sagitta friderici and the closely related S. tenuis Conant, 1896 were compared and found to be distinguishable chiefly by (1) the number of ova per unit length of the ovary, and (2) the …

Lepidactylus Triarticulatus N. Sp., A New Haustoriid Amphipod From The Northern Gulf Of Mexico, Philip B. Robertson, Charles R. Shelton

Gulf and Caribbean Research

A new haustoriid amphipod, Lepidactylus triarticulatus n. sp., from the northern Gulf of Mexico is described and illustrated. The known range is from northern Padre Island, Texas, to Grand Isle, Louisiana. The species is ecologically plastic. On surf-exposed sandy beaches it is most abundant at the highest intertidal levels, but in fine-grained sands of wave-sheltered localities it occurs throughout the intertidal region into shallow subtidal depths. In central Texas bays it has been collected subtidally at salinities as low as 10 ppt. There are differences in morphological details of peraeopod 7 between the intertidal and subtidal populations which we regard …

Notes On The Genus Probythinella Thiele, 1928 (Gastropoda: Hydrobiidae) In The Coastal Waters Of The Northern Gulf Of Mexico And The Taxonomic Status Of Vioscalba Louisianae Morrison, 1965, Richard W. Heard

Gulf and Caribbean Research

The gastropod genus Probythinella Thiele, 1928, is considered a senior synonym of Vioscalba Morrison, 1965. Probythinella louisianae (Morrison, 1965) n. comb. tentatively is recognized as a valid species distinct from the closely related P. lacustris (Baker, 1928) and P. protera Pilsbry, 1953. The eastern range of P. louisianae is extended to Mobile Bay, Alabama. Limited observations on the habitat and reproduction of P. louisianae are reported.