Microcerberus Karaman, 1933

Main Page | Isopoda > Microcerberidea > Microcerberidae > Microcerberus

Suggested Common Name: Panatlantic Cerberuses
Number of subordinate taxa: 5 species wouldwide, only 1 described in our area (see notes)
Etymology: Micro = small + Cerberus = the 3 headed gaurdian dog of Hades, likely due to the first species being found in the hyporheos of a river (akin to the River Styx of the Greek Underworld), which is also alluded to in the type species' specific epiphit. Common name refers to the extremely disjunct range of this genus (see Notes)
Taxonomic History: Microcerberus Karaman, 1933
Size Range:
Description: (adapted Wägele, Voelz & Vaun McArthur, 1995) Body elongate. Head rostral point absent. Pereonites 1-4 tergites rigid. Pereopods 2-4 coxae ring-shaped, visible dorsally. Pleopod 1 absent. ♂ pleopod 2 protopod rectangular; endopod tiny, rounded; endopod long, rod-shaped, tip pointed, often laterally curved. Pleopod 4 triramous; protopod elongate; all 3 rami similar in size, only proximally covered by pleopod 3. Uropod protopod short; exopod absent or very small, much shorter than endopod.
Type taxon: Microcerberus stygius Karaman, 1933
Notes: This genus has a unique biogeography, with 4 species occuring in Europe and at least 2 species endemic to the southeastern US. There are two competing hypotheses on the disjunct range, with one proposing that Microcerberus existed in its modern form in the Triassic before North America and Europe seperated due to the opening of the Atlantic (Wägele, Voelz & Vaun McArthur, 1995), while the other proposing that Microcerberus was a Tethyan marine genus that became stranded in inland freshwater environments after the Cretaceous marine embayments and the marine forms going extinct afterwards (Coineau & Elaine, 2001).
In addition to M. carolinensis, an undescribed species is known from Alabama. It was found in the hyporheos of Choccolocco Creek NE of Anniston in Cleburne County. This may indicate that there is a completely undescribed radiation of Microcerberids in the southeast, more research is needed to determine the full extent of it.

Subordinate taxa: Microcerberus caroliniensis

Sources

Coineau, N., & Elaine, F. (2001). Palaeobiogeography of the Freshwater Isopods Microcerberidae (Crustacea) from Caribbean and North America. In 13th International Congress of Speleology, 4th Speleological Congress of Latin América and Caribbean, 26th Brazilian Congress of Speleology. Brasilia, Brazil, July, 15-22.

Strayer, D. L., May, S. E., Nielsen, P., Wollheim, W., & Hausam, S. (1995). An endemic groundwater fauna in unglaciated eastern North America. Canadian Journal of Zoology, 73(3):502-508.

Wägele, J. W., Voelz, N. J., & Vaun McArthur, J. (1995). Older than the Atlantic Ocean: discovery of a fresh water Microcerberus (Isopoda) in North America and erection of Coxicerberus, new genus. Journal of Crustacean Biology, 15(4):733-745.

Published: Feb 15, 2023