Harderian gland ultrastructure of the black sea bottlenose dolphin (Tursiops truncatus ponticus)

Examination of the Harderian gland structure of the Black Sea bottlenose dolphin, Tursiops truncatus ponticus, at macroscopic, microscopic, and electron microscopic levels shows significant sexual dimorphism. The epithelial cells of male and female glands are different cell types, capable of producing chemically different products. Secretory cells in both sexes contain secretion granules that produce a secretion consisting mainly of proteins and carbohydrates, but thought to be sex-specific in composition. The female glands also contain lipid secretion granules. It is suggested that in the bottlenose dolphin the Harderian gland functions to produce sexually distinct pheromones and may have other physiological activities, e.g., participating in local immunological or endocrine-related reactions. © 1994 Wiley-Liss, Inc.     

Fine-scale spatial and temporal distribution patterns of large marine predators in a biodiversity hotspot

Aim

Large marine predators, such as cetaceans and sharks, play a crucial role in maintaining biodiversity patterns and ecosystem function, yet few estimates of their spatial distribution exist. We aimed to determine the species richness of large marine predators and investigate their fine-scale spatiotemporal distribution patterns to inform conservation management.

Location

The Hauraki Gulf/Tīkapa Moana/Te Moananui-ā-Toi, Aotearoa/New Zealand.

Methods

We conducted a replicate systematic aerial survey over 12 months. Flexible machine learning models were used to explore relationships between large marine predator occurrence (Bryde's whales, common and bottlenose dolphins, bronze whaler, pelagic and immature hammerhead sharks) and environmental and biotic variables, and predict their monthly distribution and associated spatially explicit uncertainty.

Results

We revealed that temporally dynamic variables, such as prey distribution and sea surface temperature, were important for predicting the occurrence of the study species and species groups. While there was variation in temporal and spatial distribution, predicted richness peaked in summer and was the highest in coastal habitats during that time, providing insight into changes in distributions over time and between species.

Main Conclusions

Temporal changes in distribution are not routinely accounted for in species distribution studies. Our approach highlights the value of multispecies surveys and the importance of considering temporally variable abiotic and biotic drivers for understanding biodiversity patterns when informing ecosystem-scale conservation planning and dynamic ocean management.     

Taxonomic review of the genus Cryphaeus Klug, 1833 (Coleoptera: Tenebrionidae: Toxicini) in Korea and description of new host fungi

A taxonomic review of the fungivorous tenebrionid genus Cryphaeus Klug in Korea is presented. Four species of this genus were identified: Cryphaeus rotundicollis Chûjô et Lee, 1993, C. albopilosus Chûjô et Lee, 1993, C. duellicus (Lewis), 1894 and a new record, C. punctatulus (Lewis), 1894. Keys, diagnoses, host fungi, habitus photographs of adults, and illustrations of diagnostic characters are provided.     

Erythrocyte membrane proteins: A modified gorter-grendel experiment

Summary The pressure-area isotherm and shear resistance of spectrin-actin monolayers indicate a close-packed structure at about 1.0 m²/mg protein. This surface area is equivalent to a thickness of about two monolayers at the erythrocyte membrane inner face. The maximum elasticity (lowest compressibility) occurs at 0.7 m²/mg protein, indicating the limit of reversible compression. The mechanical properties of the monolayers approximate those of the intact membrane, suggesting that the structures are similar and that these monolayers may account for many of thein vivo properties.