INVESTIGADORES
FERNANDEZ Marta Susana
artículos
Título:
Salt glands in the Jurassic metriorhynchid Geosaurus:
Autor/es:
FERNÁNDEZ, M. ; GASPARINI, Z.
Revista:
NATURWISSENSCHAFTEN
Editorial:
SPRINGER
Referencias:
Año: 2008 p. 79 - 84
ISSN:
0028-1042
Resumen:
Abstract The presence of salt-excreting glands in extinct
marine sauropsids has been long suspected based on skull
morphology. Previously, we described for the first time the
natural casts of salt-excreting glands in the head of the
Jurassic metriorhynchid crocodyliform Geosaurus araucanensis
marine sauropsids has been long suspected based on skull
morphology. Previously, we described for the first time the
natural casts of salt-excreting glands in the head of the
Jurassic metriorhynchid crocodyliform Geosaurus araucanensis
The presence of salt-excreting glands in extinct
marine sauropsids has been long suspected based on skull
morphology. Previously, we described for the first time the
natural casts of salt-excreting glands in the head of the
Jurassic metriorhynchid crocodyliform Geosaurus araucanensisGeosaurus araucanensis
from the Tithonian of the Vaca Muerta Formation in
the Neuquén Basin (Argentina). In the present study, saltexcreting
glands are identified in three new individuals
(adult, a sub-adult and a juvenile) referable to the same
species. New material provides significant information on
the salt glands form and function and permit integration of
evolutionary scenarios proposed on a physiological basis in
extant taxa with evidence from the fossil record. G.
araucanensis represents an advanced stage of the basic
physiological model to marine adaptations in reptiles. G.
araucanensis salt glands were hypertrophied. On this basis,
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
araucanensis salt glands were hypertrophied. On this basis,
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
physiological model to marine adaptations in reptiles. G.
araucanensis salt glands were hypertrophied. On this basis,
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
araucanensis salt glands were hypertrophied. On this basis,
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
araucanensis represents an advanced stage of the basic
physiological model to marine adaptations in reptiles. G.
araucanensis salt glands were hypertrophied. On this basis,
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
araucanensis salt glands were hypertrophied. On this basis,
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
physiological model to marine adaptations in reptiles. G.
araucanensis salt glands were hypertrophied. On this basis,
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
araucanensis salt glands were hypertrophied. On this basis,
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
G.
araucanensis represents an advanced stage of the basic
physiological model to marine adaptations in reptiles. G.
araucanensis salt glands were hypertrophied. On this basis,
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
araucanensis salt glands were hypertrophied. On this basis,
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
physiological model to marine adaptations in reptiles. G.
araucanensis salt glands were hypertrophied. On this basis,
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
araucanensis salt glands were hypertrophied. On this basis,
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
represents an advanced stage of the basic
physiological model to marine adaptations in reptiles. G.
araucanensis salt glands were hypertrophied. On this basis,
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
araucanensis salt glands were hypertrophied. On this basis,
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
G.
araucanensis salt glands were hypertrophied. On this basis,
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensis
salt glands were hypertrophied. On this basis,
it can be hypothesized that these glands had a high excretory
capability. This stage implies that G. araucanensisG. araucanensis
(like extant pelagic reptiles, e.g. cheloniids) could have
maintained constant plasma osmolality even when seawater
or osmoconforming prey were ingested. A gradual model of
marine adaptation in crocodyliforms based on physiology
(freshwater to coastal/estuarine to estuarine /marine to
pelagic life) is congruent with the phylogeny of crocodyliforms
based on skeletal morphology. The fossil record
suggests that the stage of marine pelagic adaptation was
achieved by the Early Middle Jurassic. Salt gland size in the
juvenile suggests that juveniles were, like adults, pelagic.