with an emphasis on mating activities. Many questions
about the reproductive behavior and physiology of this
species remain to be answered.
Acknowledgments
This paper is part of a masters thesis submitted to New
Mexico State University. I thank Dr N. Zucker for
suggesting this project and for her support during its
execution. Thanks also goes to my other committee
members, Drs M. Cain, R. Cole and D. Howard for
many helpful suggestions along the way. Support for
this project has come from the New Mexico State University Department of Biology, a Summer Research
Award for Excellence in Graduate Studies stipend from
the NMSU Department of Biology and the Commission on Higher Education Graduate Research Project
Award from the NMSU Graduate School.
References
Altmann, J., 1974. Observational study of behavior: Sampling methods. Behaviour 49: 227-267.
Anstensrud, M., 1992. Mate guarding and mate choice in two copepods, Lernaeocera branchialis (L.) (Pennellidae) and Lepeophtheirus pectoralis (MUller) (Caligidae), parasitic on flounder. J.
Crust. BioI. 12: 31-40.
Belk, D., 1989. Identification of species in the Conchostracan genus
Eulimnadia by egg shell morphology. J. Crust. BioI. 9: 115-125.
Creusere, F. M. & w. G. Whitford, 1976. Ecological relationships
in a desert anuran community. Herpetologica 32: 7-18.
Elwood, R. J. & 1. T. A. Dick, 1990. The amorous Gammarus: the
relationship between precopulatory duration and size-assortive
mating in G. pulex. Anim. Behav. 39: 828-833.
81
Elwood, R., J. Gibson & S. Neil, 1987. The amorous Gammarus:
size assortive mating in G. pulex. Anim. Behav. 35: 1-6.
Knoll, L. & N. Zucker, 1995. Is sexual selection operating in
the androdioecious clam shrimp, Eulimnadia texana (Crustacea:
Conchostraca)? Hydrobiologia 298 (Dev. Hydrobiol. 103): 6772.
MacKay, W. P., S. J. Loring, T. M. Frost & w. G. Whitford, 1990.
Population dynamics of a playa community in the Chihuahuan
desert. Southwest. Nat. 35: 393-402.
Martin, P. & P. Bateson, 1993. Measuring Behaviour: An introductory guide. Cambridge University Press, 2nd edn, 222 pp.
Medland, V. L., 1989. Influence of terrestrial vegetation on the production and community structure of a desert playa. Unpublished
master's thesis, New Mexico State University, Las Cruces, NM.
Otto, S. P., C. Sassaman & M. W. Feldman, 1993. Evolution of sex
determination in the Conchostracan shrimp Eulimnadia texana.
Am. Nat. 141: 329-337.
Pennak, R. w., 1989. Fresh-water invertebrates of the United States:
Protozoa to Mollusca. 3rd edn. John Wiley & Sons, Inc.: 344368.
Sassaman, C., 1989. Inbreeding and sex ratio variation in femalebiased populations of a clam shrimp, Eulimnadia texana. Bull.
mar. Sci. 45: 425-432.
Sassaman, C., 1991. Sex ratio variation in female-biased populations
of Notostracans. Hydrobiologia 212: 169-179.
Sassaman, C. & S. C. Weeks, 1993. The genetic mechanism of sex
determination in the conchostracan shrimp Eulimnadia texana.
Am. Nat. 141: 314-328.
Strenth, N. E., 1977. Successful variation of sex ratios in Eulimnadia
texana Packard (Crustacea, Conchostraca). Southwest. Nat. 22:
205-212.
Van Vactor, S. S., 1989. Hydrologic and edaphic patterns and processes leading to playa flooding. Unpublished master's thesis,
New Mexico State University, Las Cruces, NM.
Ward, P. E., 1983. Advantages and disadvantages oflarge size for
male Gammarus pulex (Crustacea: Amphipoda). Behav. Ecol.
Sociobiol. 14: 69-76.
Weeks, S., 1990. Life-history variation under varying degrees of
intraspecific competition in the tadpole shrimp Triops longicaudatus (Leconte). J. Crust. BioI. 10: 498-503.
about the reproductive behavior and physiology of this
species remain to be answered.
Acknowledgments
This paper is part of a masters thesis submitted to New
Mexico State University. I thank Dr N. Zucker for
suggesting this project and for her support during its
execution. Thanks also goes to my other committee
members, Drs M. Cain, R. Cole and D. Howard for
many helpful suggestions along the way. Support for
this project has come from the New Mexico State University Department of Biology, a Summer Research
Award for Excellence in Graduate Studies stipend from
the NMSU Department of Biology and the Commission on Higher Education Graduate Research Project
Award from the NMSU Graduate School.
References
Altmann, J., 1974. Observational study of behavior: Sampling methods. Behaviour 49: 227-267.
Anstensrud, M., 1992. Mate guarding and mate choice in two copepods, Lernaeocera branchialis (L.) (Pennellidae) and Lepeophtheirus pectoralis (MUller) (Caligidae), parasitic on flounder. J.
Crust. BioI. 12: 31-40.
Belk, D., 1989. Identification of species in the Conchostracan genus
Eulimnadia by egg shell morphology. J. Crust. BioI. 9: 115-125.
Creusere, F. M. & w. G. Whitford, 1976. Ecological relationships
in a desert anuran community. Herpetologica 32: 7-18.
Elwood, R. J. & 1. T. A. Dick, 1990. The amorous Gammarus: the
relationship between precopulatory duration and size-assortive
mating in G. pulex. Anim. Behav. 39: 828-833.
81
Elwood, R., J. Gibson & S. Neil, 1987. The amorous Gammarus:
size assortive mating in G. pulex. Anim. Behav. 35: 1-6.
Knoll, L. & N. Zucker, 1995. Is sexual selection operating in
the androdioecious clam shrimp, Eulimnadia texana (Crustacea:
Conchostraca)? Hydrobiologia 298 (Dev. Hydrobiol. 103): 6772.
MacKay, W. P., S. J. Loring, T. M. Frost & w. G. Whitford, 1990.
Population dynamics of a playa community in the Chihuahuan
desert. Southwest. Nat. 35: 393-402.
Martin, P. & P. Bateson, 1993. Measuring Behaviour: An introductory guide. Cambridge University Press, 2nd edn, 222 pp.
Medland, V. L., 1989. Influence of terrestrial vegetation on the production and community structure of a desert playa. Unpublished
master's thesis, New Mexico State University, Las Cruces, NM.
Otto, S. P., C. Sassaman & M. W. Feldman, 1993. Evolution of sex
determination in the Conchostracan shrimp Eulimnadia texana.
Am. Nat. 141: 329-337.
Pennak, R. w., 1989. Fresh-water invertebrates of the United States:
Protozoa to Mollusca. 3rd edn. John Wiley & Sons, Inc.: 344368.
Sassaman, C., 1989. Inbreeding and sex ratio variation in femalebiased populations of a clam shrimp, Eulimnadia texana. Bull.
mar. Sci. 45: 425-432.
Sassaman, C., 1991. Sex ratio variation in female-biased populations
of Notostracans. Hydrobiologia 212: 169-179.
Sassaman, C. & S. C. Weeks, 1993. The genetic mechanism of sex
determination in the conchostracan shrimp Eulimnadia texana.
Am. Nat. 141: 314-328.
Strenth, N. E., 1977. Successful variation of sex ratios in Eulimnadia
texana Packard (Crustacea, Conchostraca). Southwest. Nat. 22:
205-212.
Van Vactor, S. S., 1989. Hydrologic and edaphic patterns and processes leading to playa flooding. Unpublished master's thesis,
New Mexico State University, Las Cruces, NM.
Ward, P. E., 1983. Advantages and disadvantages oflarge size for
male Gammarus pulex (Crustacea: Amphipoda). Behav. Ecol.
Sociobiol. 14: 69-76.
Weeks, S., 1990. Life-history variation under varying degrees of
intraspecific competition in the tadpole shrimp Triops longicaudatus (Leconte). J. Crust. BioI. 10: 498-503.