Skip to content

Tadpole shrimps (Lepidurus)

Taxonomic group

Triopsidae: Lepidurus

Diagnostic features

Lepidurus is a primitive crustacean rarely seen in New Zealand fresh waters. They have a shape reminiscent of horseshoe crabs although they are not at all related. They have a large carapace that wraps around most of the body, and a multi-segmented abdomen with two long caudal filaments (tails) protruding from the carapace. They swim with paddle-like limbs under the body.

Typical habitats

Lepidurus is usually found in temporary ponds (North and South Islands) rather than permanently flowing streams.


They are omnivores, feeding on plant detritus and small aquatic invertebrates.

Indicator value

  • Hard bottom: unassigned
  • Soft bottom: unassigned

The tolerance values (ranging from 0 to 10) give an indication of which are the sensitive taxa (values of 8 or more) and which are the tolerant taxa (values of 3 or less). For more information see: Indicator species

Lepidurus are associated with temporary ponds, and new records are of conservation interest. They are not likely to be useful indicators of water quality and have not been assigned any tolerance values.