Morphologie externe et pigmentation du dauphin de Commerson, Cephalorhynchus commersonii (Lacépède, 1804), en particulier celui des îles Kerguelen

1984 ◽  
Vol 62 (12) ◽  
pp. 2465-2475 ◽  
Author(s):  
Daniel Robineau
Keyword(s):  
Sexual Dimorphism ◽  
Color Pattern ◽  
External Morphology ◽  
South American ◽  
Accurate Data ◽  
Kerguelen Islands ◽  
Black And White ◽  
Total Length ◽  
Commerson’S Dolphin ◽  
Cephalorhynchus Commersonii

Accurate data on the external morphology and color pattern of Commerson's dolphin (Cephalorhynchus commersonii) off the Kerguelen Islands were obtained by studying 11 individuals. The total length of the animals is 142,6 to 174 cm and their weight ranges between 55 and 86 kg. Their coloration is black, grey, and white; a sexual dimorphism exists in the form of genital patches. As far as I know, these dolphins are much bigger and heavier than South American specimens. Their coloration also differs from the typically black and white pattern of the latter. These characteristics suggest that the Kerguelen Islands population is isolated from the main stock of the species.

Morphological variation of Trilepida macrolepis (Peters 1857), with reappraisal of the taxonomic status of Rena affinis (Boulenger 1884) (Serpentes: Leptotyphlopidae: Epictinae)

Zootaxa ◽  
2017 ◽  
Vol 4244 (2) ◽  
pp. 246 ◽  
Author(s):  
ROBERTA R. PINTO ◽  
RONALDO FERNANDES
Keyword(s):  
Sexual Dimorphism ◽  
Morphological Variation ◽  
Taxonomic Status ◽  
Color Pattern ◽  
Identification Key ◽  
External Morphology

We report on the morphological variation (meristic, morphometric, pholidosis, and color pattern characters) and sexual dimorphism of Trilepida macrolepis. We also took the opportunity to redescribe the holotype of Rena affinis in an effort to evaluate its taxonomic status. Based on the congruence of characters from external morphology, we transfer Stenostoma affine to the genus Trilepida. We also discuss the Andean specimens previously refereed to Trilepida affinis and Trilepida macrolepis and provide an identification key for the genus Trilepida. 

scholarly journals Effect of captivity on morphology: negligible changes in external morphology mask significant changes in internal morphology

2018 ◽  
Vol 5 (5) ◽  
pp. 172470 ◽  
Author(s):  
Stephanie K. Courtney Jones ◽  
Adam J. Munn ◽  
Phillip G. Byrne
Keyword(s):  
Sexual Dimorphism ◽  
Captive Breeding ◽  
Morphological Changes ◽  
External Morphology ◽  
Wild Animals ◽  
Internal Morphology ◽  
In Captivity ◽  
Two Generations ◽  
Breeding Programmes ◽  
Source Populations

Captive breeding programmes are increasingly relied upon for threatened species management. Changes in morphology can occur in captivity, often with unknown consequences for reintroductions. Few studies have examined the morphological changes that occur in captive animals compared with wild animals. Further, the effect of multiple generations being maintained in captivity, and the potential effects of captivity on sexual dimorphism remain poorly understood. We compared external and internal morphology of captive and wild animals using house mouse ( Mus musculus ) as a model species. In addition, we looked at morphology across two captive generations, and compared morphology between sexes. We found no statistically significant differences in external morphology, but after one generation in captivity there was evidence for a shift in the internal morphology of captive-reared mice; captive-reared mice (two generations bred) had lighter combined kidney and spleen masses compared with wild-caught mice. Sexual dimorphism was maintained in captivity. Our findings demonstrate that captive breeding can alter internal morphology. Given that these morphological changes may impact organismal functioning and viability following release, further investigation is warranted. If the morphological change is shown to be maladaptive, these changes would have significant implications for captive-source populations that are used for reintroduction, including reduced survivorship.

Systematic revision and cladistic analysis of the South American genus Endeius Coiffait & Sáiz (Coleoptera: Staphylinidae)

2008 ◽  
Vol 39 (4) ◽  
pp. 381-406 ◽  
Author(s):  
Mariana Chani-Posse de Maus
Keyword(s):  
Cladistic Analysis ◽  
Identification Key ◽  
External Morphology ◽  
Female Genitalia ◽  
Valid Species ◽  
South American ◽  
The South ◽  
Systematic Revision ◽  
Male And Female

AbstractThe genus Endeius Coiffait & Sáiz, 1968 (Staphylininae: Staphylinini), distributed from Chile and Argentina through Juan Fernández Is. and Galapagos Is., is revised using characters of external morphology and male and female genitalia. Endeius comprises seven valid species: E. punctipennis (Solier), E. nitidipennis (Solier), E. subpunctipennis Coiffait & Sáiz, E. loensis Coiffait & Sáiz, E. franzi Sáiz, E. lugubris Sáiz and E. ovaliceps Coiffait. Belonuchus multipunctatus (Coiffait), comb. nov., is excluded from Endeius. An identification key to all species of the genus is provided. Monophyly of Endeius, as considered in the present study, is supported by one synapomorphy from the external morphology. Within the genus, the best supported subgroup consists of E. punctipennis (Solier), E. subpunctipennis Coiffait & Sáiz, E. loensis Coiffait & Sáiz and E. ovaliceps Coiffait.

scholarly journals Morphometric characters and their relationship in estuarine catfish

1970 ◽  
Vol 6 (2) ◽  
pp. 349-353 ◽  
Author(s):  
M Begum ◽  
Abdullah Al-Mamun ◽  
ML Islam ◽  
MJ Alam
Keyword(s):  
Sexual Dimorphism ◽  
Linear Relationship ◽  
Standard Length ◽  
Head Length ◽  
Pectoral Fin ◽  
Morphometric Characters ◽  
Total Length ◽  
Length Standard ◽  
Eye Diameter ◽  
Males And Females

The morphometric observations were made on total length, standard length, pre-caudal length, head length, eye diameter and depth of body at pectoral fin base of estuarine catfish M. gulio. Males and females showed homogeneity in characters. A linear relationship was found between total length and morphometric characters. Regression of length and weight did not deviate significantly from cube law indicating isometric growth. The fish exhibited sexual dimorphism. Keywords: Morphometric characters; Estuarine catfish; Mystus gulio DOI: 10.3329/jbau.v6i2.4833 J. Bangladesh Agril. Univ. 6(2): 349-353, 2008

scholarly journals Reproductive biology of Sympterygia bonapartii (Chondrichthyes: Rajiformes: Arhynchobatidae) in San Matías Gulf, Patagonia, Argentina

2017 ◽  
Vol 15 (1) ◽  
Author(s):  
María L. Estalles ◽  
María R. Perier ◽  
Edgardo E. Di Giácomo
Keyword(s):  
Sexual Dimorphism ◽  
Reproductive Biology ◽  
Early Spring ◽  
Egg Laying ◽  
Reproductive Pattern ◽  
Reproductive Parameters ◽  
Egg Capsules ◽  
Northern Patagonia ◽  
Total Length

ABSTRACT This study estimates and analyses the reproductive parameters and cycle of Sympterygia bonapartii in San Matías Gulf, northern Patagonia, Argentina. A total of 827 males and 1,299 females were analysed. Males ranged from 185 to 687 mm of total length (TL) and females from 180 to 742 mm TL. Sexual dimorphism was detected; females were larger, heavier, exhibited heavier livers, wider discs and matured at lager sizes than males. Immature females ranged from 180 to 625 mm TL, maturing females from 408 to 720 mm TL, mature ones from 514 to 742 mm TL and females with egg capsules from 580 to 730 mm TL. Immature males ranged from 185 to 545 mm TL, maturing ones from 410 to 620 mm TL and mature males from 505 to 687 mm TL. Size at which 50% of the skates reached maturity was estimated to be 545 mm TL for males and 594 mm TL for females. According to the reproductive indexes analysed, S. bonapartii exhibited a seasonal reproductive pattern. Mating may occur during winter-early spring and the egg-laying season, during spring and summer.

scholarly journals Biometric sexual and ontogenetic dimorphism on the marine catfish Genidens genidens (Siluriformes, Ariidae) in a tropical estuary

2017 ◽  
Vol 43 (5) ◽  
pp. 895-903
Author(s):  
Larissa G. Paiva ◽  
Luana Prestrelo ◽  
Kiani M. Sant'Anna ◽  
Marcelo Vianna
Keyword(s):  
Sexual Dimorphism ◽  
Morphological Difference ◽  
Body Measurements ◽  
Guanabara Bay ◽  
Sex Dimorphism ◽  
Total Length ◽  
Maturity Stages ◽  
Males And Females ◽  
Adipose Fin ◽  
Eye Depth

This paper aims to study the ontogenetic sexual dimorphism of Genidens genidens in Guanabara Bay, southeastern coast of Brazil. Altogether 378 specimens were anayzed (233 females and 145 males) with total length ranging from 13.3 to 43.5 cm. Specimens were measured for 12 body measurements, sex was identified and maturity stages were recorded and classified. Pearson’s linear correlation reveled a significant positive correlation between total length and all other body measures, except for base adipose fin, mouth depth and eye depth for immature females. Analyses nested PERMANOVA desing showed significant differences between maturity stages for each sex, between sexes considering or not maturity stages, indicating a variation in morphometric characteristics driven by sexual dimorphism. Differences among all maturity stages were also found, indicating an ontogenetic morphological difference. But immature individuals didn’t differ between sexes indicating that differentiation patterns starts with sexual development. The most important measures differing males and females were related to head characteristics, which appears to be key parameters to evaluate sexual differences. Due to male incubation of fertilized eggs and juvenile individuals <59 mm in their oral cavity, head measures are proposed to be sex dimorphism not related to reproduction, but with post reproductive fase due to ecological and biological needs.  [L1]Modificated  as suggested by Reviewer E.

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