Mayaweckelia yucatanensis

Phylum Arthropoda
Subphylum Crustacea
Class Malacostraca
Order Amphipoda
Family Hadziidae

Mayaweckelia yucatanensis Holsinger, 1977

Taxonomic Characterization: A small stygobitic amphipod distinguished from M. cenoticola by shorter antenna 1 which is only 50% as long as body, proportionally shorter and broader gnathopodal propods, smaller and more shallow coxal plate of pereopod 4, more narrow bases of pereopods 5-7, fewer spines on uropods and shorter telson with fewer spines (Holsinger, 1977).

Disposition of Specimen: National Museum of Natural History, Smithsonian Institution, catalog numbers USNM 151180; Museum of Texas Tech University; and the private collection of John Holsinger.

Ecological Classification: Stygobitic

Size: Adult males are up to 2.5 mm in length, while largest adult females are 3.0 mm

Number of Species in Genus: Two, both stygobitic.

Genus Range:

Mexico
- Campeche: Mayaweckelia cenoticola Holsinger, 1977 and Mayaweckelia yucatanensis Holsinger, 1977
- Quintana Roo: Mayaweckelia cenoticola Holsinger, 1977
- Yucatan: Mayaweckelia cenoticola Holsinger, 1977

Species Range: Known only from Grutas de Xtacumbilxunam, Bolonchenticul, Campeche.

Closest Related Species: Mayaweckelia yucatanensis closely resembles M. cenoticola, widespread throughout the Yucatan Peninsula.

Habitat: Freshwater limestone cave

Ecology: Collected from a pool with bat guano on the bottom and inhabited by large numbers of ostracods and shrimp (Holsinger, 1977).

Life History: Not known

Evolutionary Origins: Mayaweckelia is related to both Mexiweckelia and Hadzia but differs from these genera in several important ways. It has taxonomic affinities with marine forms and inhabits a cave situated between the Pliocene and Pleistocene shorelines of Yucatan. Holsinger (1977, 1990) concluded from this that Mayaweckelia originated from a marine ancestor by "stranding" in newly developing freshwater habitats following the regression of sea water during the late Tertiary or early Quaternary times.

Conservation Status: Know only from a single cave in the state of Campeche, Mexico.

References:

Holsinger, J.R. 1977. A new genus and two new species of subterranean amphipod crustaceans (Gammaridae s. lat.) from the Yucatán Peninsula in México. Association for Mexican Cave Studies, Bulletin 6:15-25, 7 figures.
Holsinger, J.R. 1990. Tuluweckelia cernua, a new genus and species of stygobiont amphipod crustacean (Hadziidae) from anchialine caves on the Yucatan Peninsula in Mexico. Beaufortia, 41(14): 97-107, 5 figures.
Iliffe, T.M. 1992. An annotated list of the troglobitic anchialine and freshwater cave fauna of Quintana Roo. Pp. 197-215 in: Diversidad Biológica en la Reserva de la Biosfera de Sian Ka'an, Quintana Roo, México, Vol. II, D. Navarro and E. Suárez-Morales, eds., Centro de Investigaciones de Quintana Roo, Chetumal, Q.R., Mexico, 382 pp.