Category Archives: Malacostraca

Tylos nudulus Budde-Lund

Naked Beach Pillbug (Tylos nudulus)

The Naked Beach Pillbug was described in 1906; it is known only from the beaches of Christmas Island in the Indian Ocean.

The species has never been found since its description and appears to be extinct now.



[1] D. J. James; P. T. Green; W. F. Humphreys; J. C. Z. Woinarski: Endemic species of Christmas Island, Indian Ocean. Records of the Western Australian Museum 34: 55-114. 2019


edited: 16.02.2024

Bactrurus cellulanus Koenemann & Holsinger

Indiana Groundwater Amphipod (Bactrurus cellulanus)

The Indiana Groundwater Amphipod was described in 2001; it is known only from four specimens that were found in 1962 and 1963 in a groundwater seep stream in the subbasement of Jordan Hall on the campus of the University of Indiana in Bloomington in Indiana, USA.

The species has not been collected since and is likely extinct.



[1] Steven J. Taylor; Matthew L. Niemiller: Biogeography and conservation assessment of Bactrurus groundwater amphipods (Crangonyctidae) in the central and eastern United States. Subterranean Biology 17: 1-29.2016


edited: 16.05.2022

Macrobrachium luscus (Holthuis)

Gruta del Arco Freshwater Prawn (Cryphiops luscus)

The Gruta del Arco Freshwater Prawn, which was described in 1973, is known only from its type locality: a small freshwater lake in the Grutas del Arco in the municipality of La Trinitaria, Rancho de San Rafael del Arco, Chiapas, Mexico.

This locality is now contaminated and the species wasn’t found during recent searches, it is now probably extinct.


edited: 13.11.2021

Perbrinckia gabadagei Bahir & Ng

Gabadage’s Freshwater Crab (Perbrinckia gabadagei)

Gabadage’s Freshwater Crab was described in 2005 based on two male specimens that had been collected in 1996.

This is a very small species whose carapaces reach sizes of only about 1,2 by 0,9 cm; its coloration in life is not known.

Gabadage’s Freshwater Crab is known only from its type locality, a small stream along a footpath to the Samanalakanda (Adam’s Peak), central Sri Lanka, where the animals hid themselves in wet soil under stones; it was never found since the type collection, despite several field searches. [1]



[1] Mohomed M. Bahir; Peter K. L. Ng: Descriptions of ten new species of freshwater crabs (Crustacea: Brachyura: Parathelphusidae: Ceylonothelphusa, Mahatha, Perbrinckia) from Sri Lanka. The Raffles Bulletin of Zoology 12: 47-75. 2005


edited: 03.05.2022

Hyalella imbya Rodrigues & Bueno

Mbya-Guarani Amphipod (Hyalella imbya)

This species was described in 2012 based on specimens hat had been collected in 2002 on a wetland in the municipality of Roque Gonzales, in the state of Rio Grande do Sul, southern Brazil.

The animals reach sizes of 0,48 to 0,5 cm in length, they have a smooth body surface and lack eyes.

The type locality has severely altered in recent years: the area has drained to a tributary stream, the riparian vegetation has been removed and the area was flooded; during the latest field searches again the same area was completely dried out and of course not a single specimen of the amphipod species could be found.

The Mbya-Guarani Amphipod is now very likely extinct, however, there is a slight chance that the species survives somewhere in the underground. [1]



[1] Stella Gomes Rodrigues; Alessandra Angélica de Pádua Bueno; Rodrigo Lopes Ferreira: The first hypothelminorheic Crustacea (Amphipoda, Dogielinotidae, Hyalella) from South America. ZooKeys 236: 65-80. 2021




Photos from: `Stella Gomes Rodrigues; Alessandra Angélica de Pádua Bueno; Rodrigo Lopes Ferreira: The first hypothelminorheic Crustacea (Amphipoda, Dogielinotidae, Hyalella) from South America. ZooKeys 236: 65-80. 2021`


edited: 14.11.2021

Tehuana veracruzana (Rodríguez & Smalley)

Veracruz Freshwater Crab (Tehuana veracruzana)

The Veracruz Freshwater Crab was described in 1972.

The species inhabited the Los Tuxtlas region of Veracruz, Mexico, a small mountain range of volcanic origin, where it co-occurred together with at least five additional crab species. [1]

This species’ name appears in lists of extinct species, however, I could not find out anything else so far. 



[1] Fernando Alvarez: Smalleyus tricristatus, new genus, new species, and Pseudothelphusa parabelliana, new species (Brachyura: Pseudothelphusidae) from Los Tuxtlas, Veracruz, Mexico. Proceedings of the Biological Society of Washington 102(1): 45-49. 1989


edited: 07.05.2021

Ingolfiella longipes Stock, Sket & Iliffe

Long-legged Ingolfiella Amphipod (Ingolfiella longipes)

This species was described in 1987; it is still known only from a single specimen that was collected from Walsingham Sink Cave, an anchialine cave in Hamilton Parish, Bermuda Islands.

The species has never been found since and (even if rather unlikely) might be extinct.


edited: 14.08.2022

Spherillo albospinosus (Dollfus)

White-spined Woodlouce (Spherillo albospinosus)

The White-spined Woodlouce was described in 1900; it was only known from a single male specimen that was collected near the north-western coast of the island of O’ahu, Hawaiian Islands. An additional female specimen from Kaumakani (than known as Makaweli) near the south-western coast of Kaua’i was also assigned to that species.

The species has basically never been seen since and, like so many other Hawaiian endemic species, is quite surely extinct.



[1] Fauna Hawaiiensis; being the land-fauna of the Hawaiian islands. by various authors, 1899-1913. Cambridge [Eng.]: The University Press 1913


edited: 07.08.2022

Macrobrachium hirtimanus (Olivier)

Mascarene Freshwater Prawn (Macrobrachium hirtimanus)  

The Mascarene Freshwater Prawn was described in 1811, the species was apparently endemic to the islands of Mauritius and Réunion, Mascarene Islands, where it is known to have inhabited several rivers.  

The species was last recorded in the 1980s on Réuinion and was not found in later surveys, so is now either extremely rare or may already be extinct. [1][2]  



[1] P. Keith; E. Vigneux: First capture of Macrobrachium lepidactylus (Hilgendorf, 1879) (Palaemonidae) on Réunion Island, followed by a commentary on Macrobrachium hirtimanus (Olivier, 1811). Crustaceana 73(2): 215-222. 2000 
[2] P. Keith: Freshwater fish and decapod crustacean populations on Réunion Island, with an assessmemnt of species introductions. Bulletin Français de la Pêche et de la Pisciculture. 364: 97-107. 2002  


edited: 24.04.2019