New Samoan beetle species discovered, already extinct


Holotype specimen of Bryanites graeffii. Image credit: J.K. Liebherr

From Sci News:

Bryanites graeffii: New Beetle Species Described from 150-Year-Old Museum Specimen

Jan 11, 2017 by News Staff

A new species of ground beetle has been identified by Cornell University Professor James Liebherr.

Bryanites graeffii is described from Samoa based on a single male specimen collected between 1862-1870 that was recently discovered in the Muséum national d’Histoire naturelle, Paris,” Prof. Liebherr said.

“The species epithet honors Dr. Eduard Graeffe, zoologist and naturalist from Zurich, Switzerland who collected the specimen while working in Samoa from 1862-1870. The species epithet is formed from Gräffe converted to Latin iconography, and without the terminal letter,” he explained.

The new species belongs to Bryanites, a genus of beetles in the family Carabidae that was previously known from two species represented by two specimens only, collected in 1924 from Savai’i Island, Samoa, by Edwin H. Bryan, Jr., Bernice P. Bishop Museum in Honolulu, during the Bishop Museum’s Whitney South Seas Expedition.

Much like the rest of the species within the genus, Bryanites graeffii showed vestigial flight wings and other traits associated with flight-wing loss.

However, at length of 1.62 cm it is the largest for the taxonomic group it is now assigned to.

Although this may seem way too obvious for taxonomists to overlook, the beetle’s relatives are just as obscure.

“As a result, we now have three species representing an evolutionary radiation in Samoa, all known from single specimens collected long ago,” Prof. Liebherr said.

The phylogenetics of the three Bryanites species link them to other groups from Fiji and New Zealand.

“What is the advantage of knowledge about species that existed some 90-150 years ago, but no longer? It might actually point us to the actual level of impact mankind has on natural ecosystems,” Prof. Liebherr said.

“The cause of the likely extermination of Bryanites graeffi might never be known with certainty, however, the colonization of many Pacific islands by the Polynesian rat has always been followed by the diminution or elimination of native insect species.”

“Thus, we can add another likely victim to the list of species that have been adversely impacted by mankind’s commensal voyagers.”

A detailed description of Bryanites graeffii appears in the Jan. 5 issue of the journal Zoosystematics and Evolution.

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