Phylum Arthropoda
Subphylum Crustacea
Class Copepoda
Order Cyclopoida
Family Halicyclopinae

Troglocyclops janstocki Rocha & Iliffe, 1994

	Troglocyclops janstocki: after Rocha & Iliffe, 1994

Taxonomic Characterization: "The species is the most primitive member of the Halicyclopinae because of the presence of 15-segmented antennules, mandibular palp reduced to 3 setae, one of them quite long and plumose, a bisegmented maxilary endopodite, and 3 segments in the maxilliped endopodite. These copepods possess the first pediger still distinct, being partially enclosed dorsally and laterally by a carapace-like extension of the posterior margin of the dorsal cephalic shield. The species has two apical spines on the terminal segment of the exopodite of legs 2-4, and the intercoxal sclerites of the legs 1 and 2 sexually dimorphic" (Rocha & Iliffe, 1994).

Ecological Classification: Stygobitic

Size: Female body length measures between 0.97-1.08 mm. Adult male length measures 0.71-0.86 mm

Number of Species in Genus: One

Genus Range:

Bahamas: Eleuthera Island: Troglocyclops janstocki Rocha & Iliffe, 1994
		Troglocyclops: genus range

Species Range: Known only from Hatchet Bay Cave, Eleuthera Island, Bahamas

Habitat: Anchialine limestone caves

Ecology: Found free-swimming at depths of 3 m in fully marine salinity waters.

Life History: A total of 7 females, 26 males and 23 copepodids have been collected

Evolutionary Origins: "It seems reasonable to assume that Troglocyclops diverged early from the cyclopid lineage. In Bahamian anchialine caves, its further evolution involved developing characteristic features such as the inner apical spine on the terminal segment of exopodite of legs 2-4 and the sexual dimorphism in the armature of the intercoxal sclerites of the legs 1 and 2, while retaining several primitive characters" (Rocha & Iliffe, 1994).

Conservation Status: Restricted to a single anchialine cave on Eleuthera.

References:

Links:

Contributor: Carlos Eduardo F. da Rocha, Universidade de São Paulo, Brazil