Substituent Effects in Unimolecular Ion Decompositions. III - Elucidation of Competing Alternative Pathways for the Formation of a Particular Ion

Alternative means for formation of molecular ion in mass spectr

Ecology of the Squirrel Treefrog (Hyla squirella) in Southern Arkansas

We conducted an ecological study of the Squirrel Treefrog, Hyla squirella near El Dorado, Union Co., Arkansas from May-Oct. 2013. We extended the known distribution by ~2 km and documented the first breeding occurring on 28 May and the first transformation of juveniles on 27 Aug. Three endoparasites were documented: Opalina sp., Nyctotherus cordiformis, and Physaloptera sp. larvae. We also provide information on endoparasites of Florida H. squirella as well as a summary of helminths of this frog

PHYSICAL FACTORS REGULATING MACROBENTHIC COMMUNITY STRUCTURE ON A SOUTH AFRICAN ESTUARINE FLOOD-TIDAL DELTA

Multivariate techniques were used to identify environmental parameters affecting macrobenthic communities on the flood-tidal delta of the Nahoon Estuary and adjacent beach near East London on the south-east coast of South Africa. Water content of sediments, temperature and exposure were identified as important parameters regulating differences in community structure between high-shore and subtidal sites, and between beach sites of varying elevation. High organic content was important for similarity of communities at sites farthest from the mouth and for distinctness of these communities from the others. Sediment particle size, compactness and current velocity contributed to similar communities of channel sites and their variation from those of other sites, and to distinctness of the lowest beach site from higher beach sites. Sites in the mouth and in the middle of the flood-tidal delta, with similarities in community structure, had varying values for all the measured environmental variables and none of these parameters could explain why these sites had similar communities. In summary, no over-riding parameter was shown to dominate the abiotic driving forces at all sampling sites, and different variables were important for structuring communities at different sites.Afr. J. mar. Sci. 25: 263–27

Intertidal zonation of macroinfauna on a dissipative, sandy beach at De Panne (Belgium): a pilot study

To elucidate vertical (= from high to low water mark) macroinfaunal community patterns on little-studied Belgian dissipative sandy beaches, macroinfauna was sampled at eight stations along a seaward transect at De Panne. Mean sand particle size was 196 µm, and the beach slope was ca. 1 : 90. Nineteen species were collected (excluding non-quantitatively sampled species), nine of which were polychaetes and eight were crustaceans. Total macroinfaunal abundance per station ranged from 103 to 585 ind./ m². Polychaetes and crustaceans were numerically dominant, comprising more than 98% of total numbers. Seaward spatial distributions of abundant species were interpreted to represent three biotic zones or macroinfaunal communities, as suggested by a kite diagram, TWINSPAN and CCA. These findings indicate that an environmental gradient of seaward variation in elevation above MLWS, sediment gravel fraction and sediment organic content largely determines the sandy beach community structure at De Panne

A new species of Cosmocerca (Nematoda: Cosmoceridae and other helminths in Cyrtodactylus gubaot (Squamata: Gekkonidae) from the Philippines

Cosmocerca leytensis sp. nov. (Ascaridida, Cosmocercidae) from the large intestine of Cyrtodactylus gubaot (Squamata: Gekkonidae) collected on Leyte Island, Philippines is described and illustrated. Cosmocerca leytensis sp. nov. is the 30th species assigned to the genus, the 4th from the Oriental region, and the first from the Philippine Islands. The new species is most similar to those species possessing 4 pairs of plectanes, i.e., C. archeyi, C. australis, C. oroensis, and C sardiniae. Cosmocerca sardiniae lacks lateral alae; C. archeyi, C. australis, C. leytensis sp. nov. and C. oroensis possess lateral alae. Spicule length of C. oroensis is less than 75 ìm, while C. archeyi, C. australis, and C. leytensis sp. nov. have spicule lengths greater than 75 ìm. Males of C. australis possess 2 pairs of rosette caudal papillae, which are lacking in C. archeyi and C. leytensis sp. nov. Females of C. archeyi posses a conical tail, females of C. leytensis sp. nov. have a rounded posterior end supporting a flexible filament

Comparative Study of Helminth Parasites of the Many-Ribbed Salamander, Eurycea multiplicata and Oklahoma Salamander, Eurycea tynerensis (Caudata: Plethodontidae), from Arkansas and Oklahoma, A

Ninety many-ribbed salamanders, Eurycea multiplicata and 135 Oklahoma salamanders, Eurycea tynerensis were collected between April 2010 and April 2014 from 14 counties of Arkansas and McCurtain County, Oklahoma (E. multiplicata only) and examined for helminth parasites. Twelve (13%) E. multiplicata were infected, including two (2%) each with Brachycoelium salamandrae, Bothriocephalus rarus, Batracholandros magnavulvaris, Cosmocercoides variabilis, and Omeia papillocauda, and one (1%) each with an oligacanthorhynchid cystacanth and Fessisentis vancleavei. Forty-one (30%) of the E. tynerensis were infected, including seven (5%) with Gorgoderina tenua, two (1%) each with Phyllodistomum solidum and cyclophyllidean tapeworm cysticerci, one (0.7%) with Cylindrotaenia americana, six (3%) with B. rarus, eight (12%) with Desmognathinema nantahalaensis, 10 (7%) with O. papillocauda, two (1%) with Amphibiocapillaria tritonipunctata and six (4%) with F. vancleavei. We document 13 new host and two new distributional records for helminths of these salamanders. In addition, a summary of the endoparasites of E. multiplicata and E. tynerensis is provided