Morphometric characterization of thalassohaline Artemia
franciscana populations from the Colombian Caribbean
W.N.
Camargo, J.S. Ely, P. Sorgeloos-2003
Journal
of Biogeography, 30(5): 697
Abstract:
Aim
To establish possible interpopulation
relationships among Colombian Artemia franciscana (Crustacea,
Anostraca) populations.
Location
Colombian Caribbean coast (Manaure,
Galerazamba, Salina Cero and Tayrona) and a similar thalassohaline reference
population from San Francisco Bay (SFB-USA).
Methods
Morphometric characters of male and female
cultured individuals of A. franciscana were measured. The populations
were grouped according to: (1) population type (populations grouped
according to two broad regions of origin: North America and the Caribbean
coast), and (2) specific geographical origin (populations selected according
to five specific local origins: Manaure, Galerazamba, Salina Cero, Tayrona
and SFB) and evaluated using forward stepwise discriminant analysis (SPSS,
Ver. 10).
Results
Optimal discriminant variables for males
grouped by the type of population were left setae and antenna length, and
for females they were abdominal length and antenna length. However, for
males grouped by their specific geographical origin, the optimal variables
were furca length, left setae, antenna length, eye separation, abdominal
width and abdominal length, and for the females, they were furca length,
abdominal length, left setae and eye separation. Male and female Colombian
Caribbean populations were separated from the North American populations.
However, our results show that the classification based on male characters
provides better group membership than females.
Main
conclusions
Male
morphometric characters separated the type of population groups more clearly
than the female characters, because all Colombian populations were correctly
positioned in the Caribbean coast region and the SFB population in the North
American region, with no overlapping between the two types, as was the case
for the female individuals. Likewise, male individuals correctly position
the Salina Cero population to its neighbouring Galerazamba population and to
the other Colombian populations. In contrast, female individuals from Salina
Cero did not cluster with the other Colombian coast populations
(Galerazamba, Tayrona and Manaure) or with the SFB population.
(Fisheries and Illinois Aquaculture
Center, Southern Illinois University at Carbondale, Carbondale, IL 62901,
USA. E-mail: wcamargo@siu.edu)