Researchers discover 24 skink species
Half of newly described species may be extinct
already:
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A Caicos Islands skink. Photo: Joseph Burgess
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Researchers have discovered 24 skink species in the Caribbean,
including re-establishing nine species that had been described but were
thought to be inaccurate descriptions.
This, according to the paper published in Zootaxa, puts the number of
skink species in the Caribbean from six to 39.
Blair Hedges, a biology professor, the leader of the research team,
said that half of the newly described species might be extinct and all
of the species on the list are likely to be endangered on the Caribbean
islands.
The researchers discovered the new species primarily by examining
museum specimens.
They used DNA sequencing and combined that with classic taxonomic
techniques such as counting the number of scales as well as describing
the shape of those scales.
A unique aspect of the skinks is they have a placenta, similar to a
human placenta that enables these lizards to gestate their offspring for
up to a year before live birth. Hedges said that this gestation period
may have given predators an edge in seeking out and consuming the
females, which are slower when pregnant.
Hedges believes that the introduction of the mongoose to control rats
in sugarcane fields is responsible for the low numbers of skinks on the
islands.
"The mongoose is the predator we believe is responsible for many of
the species' close-to-extinction status in the Caribbean," Hedges said
in a press release put out by Penn State University. "Our data show that
the mongoose, which was introduced from India in 1872 and spread around
the islands over the next three decades, has nearly exterminated this
entire reptile fauna, which had gone largely unnoticed by scientists and
conservationists until now."
Hedges said the reason these species went unnoticed for so long was
the fact that the skinks had already disappeared by the start of the
20th century and nobody was really studying them.
He also said that the use of DNA testing followed up with the
taxonomic work required to validate a species are techniques that were
not available 100 years ago.
- Reptile channel.com
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