Two new species of bass described:
UGA ecologists document two new species of bass
A team led by University of Georgia ecologists documented two new species of black bass, Bartram’s bass and Altamaha bass, in a new
paper.
Both species previously were considered synonymous with redeye bass, but each has distinctive physical characteristics. Bartram’s bass are light gold, with patterned dark brown blotches on the sides, a rosy-pink fin and a mottled belly. They have an oval tooth patch in their mouth and carmine-red eyes with a black pupil ringed by a thin gold margin. They can grow to 15 inches long.
Altamaha bass, or Micropterus calliurus, have light gold scales with olive margins, darker brown blotches on their sides and orange on the edges of their fins. They have a small oval tooth patch in their mouth and red eyes with a thin gold margin around the pupil. They can grow to 14 inches long.
But the team members didn’t just note the physical differences — they also documented the genetics.
“It used to be that you’d have to go out and catch the fish, bring it in, count the scales, measure the tail, measure this and that, write a description, and you’re done,” said Mary Freeman, co-author of the study and adjunct faculty at the Odum School. “Now there is also genetic characterization. In this case, there’s genetic characterization of every single individual used to describe that fish to prevent including hybrid specimens.”
Identifying “pure” individual fish required examining mitochondrial DNA and using bioinformatics techniques to compare short DNA fragments in the nuclear genome. More than 100 animals were referenced in the documentation for the two new species, and the full dataset includes 570 individuals, Bartram’s and Altamaha bass, but also smallmouth, largemouth, northern spotted, shoal, Tallapoosa, redeye and Alabama bass.
UGA ecologists document two new species of bass - UGA Today
Also a new extinct crocodyliform discovered:
Tiny extinct crocodyliform with unusual teeth discovered in Montana
Measuring no more than 2 feet long from nose to tip of tail, young Elton was about the size of a big lizard, according to Montana State University professor of paleontology David Varricchio. Had it lived to be full grown, Elton would have measured no longer than 3 feet, far smaller than most members of the Neosuchia clade to which it and its distant relatives belong.
The clade includes modern crocodilians and their closest extinct relatives, almost all of them semiaquatic or marine carnivores with simple, conical teeth.
Elton, by contrast, lived on the land, probably feasting on both plants and insects or small animals with its assortment of differently shaped and specialized teeth. Its unique anatomy reveals that it was part of a new, previously unrecognized family of crocodyliforms endemic to the Cretaceous of North America.
The extinct animal, which Allen and the paper's co-authors later named Thikarisuchus xenodentes for its strange, sheathed teeth, has provided new information about the paleoecology of the Blackleaf ecosystem and about patterns of evolution in the croc family tree.
"The majority of diversity of crocodyliforms is in the past. There were fully marine crocs, fully terrestrial crocs, herbivorous crocs, omnivores and some that cracked shells," he said. "That amazed me and made me want to get into this more specific realm of paleontology."
Tiny extinct crocodyliform with unusual teeth discovered in Montana
