Cumella bacescui

Phylum Arthropoda
Subphylum Crustacea
Class Malacostraca
Order Cumacea
Family Nannastacidae

Cumella (Cumewingia) bacescui Petrescu & Iliffe, 1992

Taxonomic Characterization: Small cumacean with slightly hairy integument. The carapace represents 1/3 of the length of the body. The ocelli crown consists of 7 lenses, 5 on the rostrum (2 pigmented) and 2 on the pseudorostrum (absent in the female). The antennal notch is more prominent at the male. In the female, the integument of the abdomen and the pleotelson is scaled (Petrescu & Iliffe, 1992).

Disposition of Specimens: Grigore Antipa, Natural History Museum, collection number 747, inventory number 49,479.

Ecological Classification: Probably stygophilic (troglophilic)

Size: Adult male length ranged from 1.62-1.95 mm; adult ovigerous female 1.43 mm.

Number of Species in Genus: More than 60 species are included in the genus Cumella, while the subgenus Cumewingia contains about 20 species. None are known to be stygobitic.

Subgenus Range:

Australia: C. (C.) turgidula Hale, 1945
Bahamas:
- North Andros Island Blue Holes:
  - C. (C.) anae Petrescu & Iliffe, 1992
  - C. (C.) angelae Petrescu & Iliffe, 1992
  - C. (C.) bacescui Petrescu & Iliffe, 1992
  - C. (C.) caribbeana Bacescu, 1971
Indonesia, Malaysia, Thailand, Australia: C. (C.) hispida Hale, 1945; C. (C.) indosinica Zimmer, 1952
Japan: C. (C.) alveata Gamo, 1964, C. (C.) glaberata Gamo, 1962
Mediterranean, Black Sea: C. (C.) limicola Sars, 1879
Red Sea: C. (C.) schieckei Bacescu & Muradian, 1975; C. (C.) forficuloides Bacescu & Muradian, 1975 and C. (C.) limicoloides Bacescu & Muradian, 1975
Thailand: C. (C.) forficula Calman, 1911, C. (C.) siamensis Zimmer, 1952
Tropical Western Atlantic: C. (C.) caribbeana Bacescu, 1971; C. (C.) clavicauda Calman, 1911; C. (C.) leptopus Calman, 1911, C. (C.) serrata Calman, 1911; C. (C.) siankaana Donath, 1992; C. (C.) vicina Zimmer, 1944

Species Range: Rat Cay Blue Hole, Rat Cay, or Bluehole Cay Blue Hole (Forfar Blue Hole), Stafford Creek, both on North Andros Island, Great Bahama Bank, Bahamas. Samples collected from these two caves were combined so the specific collection location is not known.

Closest Related Species: Resembles Cumella garrityi Bacescu & Muradian, 1977

Habitat: Marine limestone caves (ocean Blue Holes)

Ecology: Specimens were collected using a 0.3 mm mesh plankton net with a mouth diameter of 0.45 m set in the approximately 0.25 m/sec suck or blow currents at the mouth of Rat Cay and Bluehole Cay caves on Andros Island. Tidal inequalities across the broad, shallow water Bahama banks generate strong reversing currents through the caves with a period 2 to 3 hours out of phase with tides in the surrounding sea (Warner and Moore, 1984). While the inward or 'suck' currents draw slightly turbid seawater with normal temperature, salinity and dissolved oxygen levels into the caves, the outward flowing or 'blow' water is clearer, slightly cooler and may contain hydrogen sulfide.
Cumaceans were most abundant in the blow waters emanating from the Blue Holes. A total of 65 specimens were obtained in three blow plankton samples, while only 3 specimens were found in two suck samples. This indicates that these cumaceans are originating from the cave itself and are at least stygophiles if not stygobites. Blow samples in general were characterized by comparatively greater amounts of sand, crustacean exuvia, ostracod valves, fecal pellets, hydroid pieces, foraminiferans, small gastropods, ostracods, harpacticoid copepods, amphipods and isopods. Conversely, suck samples contained relatively more algal fragments and filaments, planktonic copepods and crustacean larvae (Warner & Moore, 1984).

Life History: The seven specimens have been collected included six adult males and one ovigerous female.

Evolutionary Origins: Probably originated from an open water ancestor.

Conservation Status: Restricted to Rat Cay or Bluehole Cay Blue Holes, North Andros Island, Bahamas.

References:

Bacescu, M. 1971. New Cumacea from the littoral waters of Florida (Caribbean Sea). Travaux du Museum d'Histoire Naturelle Grigore Antipa, 11:5-24.
Bacescu, M. and Z. Muradian. 1975. New Cumacea from the Red Sea. Travaux du Museum d'Histoire Naturelle Grigore Antipa, 16:35-70.
Bacescu, M. and Z. Muradian. 1977. Species of the genus Cumella (Crustacea, Nannastacidae) from the Western Tropical Atlantic, Travaux du Museum d'Histoire Naturelle Grigore Antipa, 18:89-102.
Calman, W.T. 1911. On new or rare crustacea of the order Cumacea from the collection of the Copenhagen Museum. Part II. The families Nannastacidae and Diastylidae. Trans. zool. Soc. Land, 18:341-400.
Petrescu, I. and T.M. Iliffe. 1992. Contributions to the knowledge of the cumacean species (Crustacea, Cumacea) of British Blue Holes (Andros Island, Bahamas Islands). Travaux du Museum d'Historie Naturelle Grigore Antipa, 32:283-301, 10 figures.
Warner, George F. and C.A.M. Moore. 1984. Ecological studies in the marine Blue Holes of Andros Island, Bahamas. Cave Science, 11(1):30-44.

The Cumacean Page contains information on systematics, ecology, and biogeography of the cumaceans of the World. It is one part of a PEET project (Partnerships for Enhancing Expertise in Taxonomy) funded by the Systematic Biology Program of the United States National Science Foundation.

Contributor: Iorgu Petrescu, Grigore Antipa Museum of Natural History, Bucharest, Romania