Speleophriopsis scottodicarloi (Boxshall & Iliffe, 1990)
Speleophriopsis scottodicarloi: dorsal view, after Boxshall & Iliffe, 1990
Synonyms: Speleophria scottodicarloi Boxshall & Iliffe, 1990
Taxonomic Characterization: The prosome is large and 4-segmented with a smooth surface. The rostrum tapers in the ventral direction and is free from the labrum. The urosome is 5-segmented and the genital and 1st abdominal somites fuse to form a genital double somite. The antennule is 27-segmented; the endopod of the antenna is 2-segmented and the exopod is 7-segmented. The mandible has one large ventral tooth and 8 smaller teeth. The maxilla is 6-segmented and the maxilliped is 8-segmented. Legs 1-4 are biramous with 3-segmented rami, except for the 2-segmented endopod of the 1st leg. The 5th leg is uniramous and lacks inner margin seta on the 2nd exopod. The 6th leg is represented by a plate overlying the genital opening.
Disposition of Specimens: Female holotype deposited in the British Museum of Natural History, (registration number 1989.963).
Ecological Classification: Stygobitic
Size: Total body length of adult female 583 microns.
Number of Species in Genus: 5, all anchialine. S. scottodicarloi and S. campaneri were originally described as species of Speleophria but were transferred to Speleophriopsis by Jaume & Boxshall (1996).
Species Range: Known only from Chalk Cave, Smith's Parish, Bermuda
(Boxshall & Iliffe, 1990).
Closest Related Species: S. scottodicarloi is similar to S. campaneri, from anchialine caves in Palau, in limb segmentation and armature and in the presence of a large carapace concealing the 1st pedigerous somite. S. scottodicarloi appears to be closely related to Speleophria with species in Bermuda and the Balearic Islands, although much of the resemblance is due to shared primitive character states (Jaume & Boxshall, 1996).
Habitat: Anchialine limestone caves
Ecology: S. scottodicarloi inhabits Chalk Cave which is 50 m from Harrington Sound. The specimen was collected from a clear pool in total darkness within the cave using a dip net at 0-1.5 m depths. The salinity at the surface of the pool was 16.0 ppt and 26.3 ppt at 1 m, corresponding temperatures were 20.8 C and 21.6 C. The pool appears to be isolated from any direct connection with the open sea and is inhabited by other stygobitic crustaceans.
Life History: Only one female specimen was collected.
Evolutionary Origins: Speleophria and Speleophriopsis display a circumtropical distribution which fits within the ancient limits of the early Tethys Sea (Jaume & Boxshall, 1996). They are limited to anchialine habitats with salinities close to seawater and thus, their potential for dispersal is extremely limited. They appear to have survived in place during the Upper Tertiary when the entire Mediterranean Sea dried up with the corresponding extinction of its marine biota. The discovery of stygobiont misophrioids on continental, non-volcanic islands casts doubt on the previous proposed hypothesis for a deep sea origin of anchialine lineages (Jaume & Boxshall, 1996).
Conservation Status: This species is considered to be critically endangered (IUCN, 2000). It is restricted to a single anchialine cave in Bermuda.
Contributor: Geoffrey A. Boxshall, Natural History Museum, London, UK
|Please email us your comments and questions.||Last modified:|