Bermuda cave amphipod (Pseudoniphargus grandimanus)

KingdomAnimalia
PhylumArthropoda
ClassCrustacea
OrderAmphipoda
FamilyHadziidae
GenusPseudoniphargus (1)
SizeTotal male body length: 6.5 - 8 mm (2)

Classified as Critically Endangered (CR) on the IUCN Red List 2006 (1).

This is a colourless, eyeless amphipod that lacks a rostrum. The upper lip is broadly rounded and the lower lip has large inner lobes (2).

Recorded from wells, waterworks and cave waters in Hamilton, St. George’s, Devonshire, Paget, Smith’s and Warwick Parishes, Bermuda, including Church, Wonderland, Admiral’s and Government Quarry Caves (2).

Found in a wide range of anchialine limestone cave and groundwater habitats throughout the entire salinity range, although most frequently in low salinity areas. Juveniles are found far closer (11-180 m) to the sea coast than adults (147-853 m) (2).

The fact that large adults, but notably no specimens carrying eggs, have been found further from the sea coast than juveniles could indicate a dependence on anchialine/marine habitats for reproduction, and also that juveniles migrate inland to mature (3).

Nothing else is known of this Bermuda cave amphipod’s biology.

The threats to this species are unknown.

There are currently no conservation measures underway targeting this species.

For more information on this atyid shrimp see:

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact: arkive@wildscreen.org.uk

  1. IUCN Red List (January, 2007)
    http://www.iucnredlist.org
  2. Anchialine Caves and Cave Fauna of the World (February, 2007)
    http://www.tamug.edu/cavebiology/fauna/amphipods/P_grandimanus.html
  3. Stock, J.H., Holsinger, J.R., Sket, B. and Iliffe, T.M. (1986) Two new species of Pseudoniphargus (Amphipoda), in Bermudian groundwaters. Zoologica Scripta, 15(3): 237 - 249.