Bifurcitus ducalis
Bifurcitus ducalis, formerly Megadytes ducalis, is a species of water beetle in the family Dytiscidae. It is the largest species in the family. Until recently, the species was only known from a single specimen that was collected in the 19th century from Brazil, but more specimens, also collected in the 19th century from Brazil, were discovered in 2019. Although listed as extinct by the IUCN, the limited studies conducted on water beetles in Brazil means that it might still survive.
History
The first specimen of B. ducalis was collected in the 19th century from an unknown locality in Brazil and is kept at the Natural [History Museum, London]. Rumors indicated it was found in the bottom of a canoe in the Amazon.In 2019, a study reported 10 additional specimens, all collected in the late 19th century, discovered incidentally in the National [Museum of Natural History, France|National Museum of Natural History of France]. While the original holotype lacked any exact location data, the new specimens all indicate that they were collected in Santo Antonio da Barra in the southern part of Bahia, Brazil. Villagers in the region were involved in insect trade, capturing the much sought after specimens of Hypocephalus armatus found around the region.
As a consequence of the lack of recent records, the IUCN lists it as extinct. Considering the absence of information about the species and the limited studies conducted on water beetles in Brazil, it might still survive.