Crangon alba Holmes, 1900

Common name(s): Stout crangon

Synonyms: Crangon alba side view
Crangon alba dorsal view
Phylum Arthropoda
Subphylum Crustacea
Class Malacostraca
Subclass Eumalacostraca
Order Decapoda
Infraorder Caridea
Crangon alba captured in Padilla Bay tide flats
(Photos by: Dave Cowles, July 2008)
Description:   As with other members of Family Crangonidae, this species has a subchelate pereopod 1 (photo) and the carpus of pereopod 2 is not subdivided into several units. Crangon alba has a very short rostrum (photo).  The dactyl of leg 5 (the last walking leg) is not broad and flattened.  The eyestalks are not parallel nor shielded by a hood made of spines (photo).  Its carapace is smooth.  It has a single median dorsal spine shortly behind the rostrum (photo) but no submedian spines.  Abdominal segment 5 has no spines on the upper posterolateral margins (photo). Abdominal segment 6 has no prominent longitudinal ridges on the dorsal surface (photo) and also has no median groove on the ventral surface (photo).

How to Distinguish from Similar Species:   Crangon franciscorum has a spine on the upper posterolateral margin of abdominal segment 5.  C. handi, C. alaskensis, and C. nigricauda have a median ventral groove on abdominal segment 6.

Geographical Range: East Pacific

Depth Range:

Habitat:

Biology/Natural History: Crangon shrimp are common on sandy bottoms, where their camouflage helps them blend in well.  If disturbed they will often swim down to the sand, rest their ventral surface on it, and quickly burrow out of sight (using their legs, but probably also using their pleopods--see the photo below and this movie).



 

References:

Dichotomous Keys:
  Kozloff 1987, 1996
 
 
 

General References:
 

Scientific Articles:
Campos, Joana, Claudia Moreira, Fabiana Freitas, and Henk W. van der Veer, 2012.  Short review of the eco-geography of Crangon.  Journal of Crustacean Biology 32:2 pp 159-169

  

Web sites:


General Notes and Observations:  Locations, abundances, unusual behaviors:
 

In this underside (ventral) view of the head the subchelate first pereopods can be clearly seen.
Head underside
 

In this dorsal view of the head the small rostrum and the single median spine behind it can be seen.  The arrangement of the eyestalks can also be clearly seen.

Head
 

The upper posterolateral margin of abdominal segment 5 has no spines, as seen in this dorsal view.  Anterior is to the right, and segment 6 is to the left.
Dorsal abdominal segment 5

Abdominal segment 6 has a dorsal median groove (sulcus) but no median ridge.  Anterior is to the right and the tailfan is to the left.
Abdominal segment 6 dorsal
 

The ventral sides of abdominal segments 5 (right) and 6 (left) are both smooth and clear, with no median groove (sulcus).
Abdominal segments 5-6 ventral
This view is an oblique view of the right pleura and the ventral side from the right side of the shrimp.  The base of leg 5 can be seen at the right.

The feathery exopods of the pleopods are typically held out to the side.  They are used for swimming and likely also for burrowing.
Pleopods
 
 

This individual was carrying a large batch of white eggs.
Eggs



Authors and Editors of Page:
Dave Cowles (2008):  Created original page
CSS coding for page developed by Jonathan Cowles (2007)