Results 21 to 30 of about 17,364 (267)

A review of the behaviours of the Chondrichthyes: a multi-species ethogram for the chimaeras, sharks, and rays

Behaviour, 2023
In this review of the behavioural patterns of chondrichthyan fishes, we have strived to produce a comprehensive catalogue of events and states and develop standardized terminology.
A. Klimley, I. F. Porcher, Eric E. G. Clua, H. L. Pratt   +3 more
semanticscholar   +1 more source

Rare evidence of shark-on-shark trophic interactions in the fossil record [PDF]

Acta Palaeontologica Polonica, 2021
Direct evidence of chondrichthyan trophic interactions in the fossil record is largely limited to bite traces on prey items but may also be found within the gut contents of exceptionally well-preserved individuals or as inclusions within coprolites ...
VICTOR J. PEREZ, STEPHEN J. GODFREY, PHILLIP F. CHAPMAN   +2 more
doaj   +1 more source

The evolution of sexual dimorphism in Chondrichthyes: drivers, uncertainties, and future directions

Environmental Biology of Fishes, 2023
Sexual dimorphisms are abundant in natural systems; however, their ecological and evolutionary significance have largely been neglected with respect to Chondrichthyes.
J. Gayford
semanticscholar   +1 more source

Differences in the occurrence and abundance of batoids across an oceanic archipelago using complementary data sources: Implications for conservation

Ecology and Evolution, 2021
Batoids, distributed from shallow to abyssal depths, are considerably vulnerable to anthropogenic threats. Data deficiencies on the distribution patterns of batoids, however, challenge their effective management and conservation.
Fernando Tuya, Ricardo Aguilar, Fernando Espino, Nestor E. Bosch, Eva K. M. Meyers, David Jiménez‐Alvarado, Jose J. Castro, Francisco Otero‐Ferrer, Ricardo Haroun   +8 more
doaj   +1 more source

Testicular Morphology and Spermatogenesis in Potamotrygon motoro: Insights Into Reproduction of Freshwater Stingrays. [PDF]

J Morphol
Electron microscopy of Potamotrygon motoro spermatozoa. a – Illustration of a schematic sperm cell depicting the helical head, intermediate piece (midpiece), and flagellum. b ‐ Helical heads (Hh) of spermatozoa inserted into the cytoplasm of Sertoli cells (S) through openings in the plasma membrane. Scales: 10 μm.
Delgado MLR, Quirino PP, Gomes-Silva L, Dzyuba V, Dzyuba B, Ninhaus-Silveira A, Veríssimo-Silveira R.   +6 more
europepmc   +2 more sources

The Phylogeny of Rays and Skates (Chondrichthyes: Elasmobranchii) Based on Morphological Characters Revisited

Diversity, 2022
Elasmobranchii are relatively well-studied. However, numerous phylogenetic uncertainties about their relationships remain. Here, we revisit the phylogenetic evidence based on a detailed morphological re-evaluation of all the major extant batomorph clades
Eduardo Villalobos‐Segura, G. Marramà, G. Carnevale, Kerin M. Claeson, C. Underwood, G. Naylor, J. Kriwet   +6 more
semanticscholar   +1 more source

Environmental DNA captures elasmobranch diversity in a temperate marine ecosystem

Environmental DNA, 2022
Many sharks, skates, and rays (elasmobranchs) are highly threatened by the activities of commercial fisheries, and a clear understanding of their distributions, diversity, and abundance can guide protective measures.
Zifang Liu, Rupert A. Collins, Charles Baillie, Sophie Rainbird, Rachel Brittain, Andrew M. Griffiths, David W. Sims, Stefano Mariani, Martin J. Genner   +8 more
doaj   +1 more source

Heterodonty and ontogenetic shift dynamics in the dentition of the tiger shark Galeocerdo cuvier (Chondrichthyes, Galeocerdidae)

Journal of Anatomy, 2022
The lifelong tooth replacement in elasmobranch fishes (sharks, rays and skates) has led to the assemblage of a great number of teeth from fossil and extant species, rendering tooth morphology an important character for taxonomic descriptions, analysing ...
Julia Türtscher, Patrick L. Jambura, Faviel A. López‐Romero, René Kindlimann, Keiichi Sato, Taketeru Tomita, J. Kriwet   +6 more
semanticscholar   +1 more source

First record of chimaeroid fish Ischyodus from the Upper Jurassic of southwestern Gondwana [PDF]

Acta Palaeontologica Polonica, 2021
This study presents two specimens of Chimaeriformes from Upper Jurassic strata of central Chile. The material was recovered from Tithonian levels of the Baños del Flaco Formation and includes two different individuals, one preserving two articulated ...
Rodrigo A. Otero, Constanza Figueroa Bravo, Paula Soto-Huenchumán, Sara Fernández-Collemann, Ana M. Valenzuela-Toro, Carolina S. Gutstein   +5 more
doaj   +1 more source

Late Mesozoic marine Antarctic fishes: future perspectives based on the newly collections recovered in the Ameghino and López de Bertodano Formations [PDF]

Research & Knowledge, 2017
Nowadays, notothenioids are the teleostean group that dominates marine Antarctic waters. However, during the Mesozoic a diverse ichthyofauna inhabited the sea that surrounded Antarctic.
Soledad Gouiric-Cavalli, Leonel Acosta Burllaile, Ari Iglesias, Juan J. Moly, José P. O´Gorman, Marcelo Reguero, Sergio Santillana, Marianella Talevi, Carolina Vieytes, Mauricio A. Bigurrarena Ojeda, Jorge Lusky   +10 more
doaj   +1 more source