Mixture of parthenogenetic
and zygogenetic brine shrimp Artemia (Branchiopoda: Anostraca) in
commercial cyst lots from Great Salt Lake, UT, USA
R. Campos-Ramos, A.M. Maeda-Martínez, H. Obregón-Barboza,
G. Murugan, D.A. Guerrero-Tortolero, P. Monsalvo-Spencer-2003
Journal of Experimental Marine Biology and Ecology, 296(2): 243-251
Abstract:
The brine shrimp Artemia is one of the most
studied animals in the world. A large part of the knowledge of this
crustacean is based on cysts harvested from two main sources; the Great Salt
Lake, UT (GSL), and the San Francisco Bay salterns, CA (SFB), USA. Artemia
populations from these habitats are recognized to belong to a single
zygogenetic species, Artemia franciscana Kellogg, 1906. However, the
GSL Artemia has been in doubt for more than a century about the
existence of parthenogenetic reproduction. By using morphological,
reproductive, and molecular analyses, we report that commercial GSL cyst
lots contained two different brine shrimp species; a parthenogenetic (60%)
and a zygogenetic (A. franciscana) (40%). From this finding, at least
three hypotheses can be drawn. The parthenogenetic Artemia is native
of GSL, or it was introduced to GSL, or foreign parthenogenetic cysts were
mixed with A. franciscana cysts and canned for commercial
distribution. Researchers using brine shrimp cysts from GSL should therefore
pay careful attention to the correct identity of the species under study.
The potential of an easy and unnoticed introduction of parthenogenetic Artemia
into America is discussed.
(Centro de
Investigaciones, Biológicas del Noroeste S.C. Mar Bermejo 195, Col. Playa
de Santa Rita, La Paz, B.C.S., C.P. 23090, Mexico, e-mail of A.M. Maeda-Martínez:
almaeda@cibnor.mx)