Differential reproduction of coexisting clones of triploid parthenogenetic Trichoniscus pusillus (Isopoda, Crustacea)

Christensen, B., Noer, H. and Theisen, B. F. 1987. Differential reproduction of coexisting clones of triploid parthenogenetic Trichoniscus pusillus (Isopoda, Crustacea). ‐ Hereditas 106: 89–95. Lund, Sweden. ISSN 0018–0661. Received April 17, 1986 Reproduction of four clones in triploid parthenogenetic Trichoniscus pusillus was studied at five closely situated stations differing strongly in relative frequencies of clones. The results indicated 2–3 peaks in number of brood‐carrying females together with seasonal trends in brood size. The four clones were similar in percentage of brood‐carrying females and seasonal trends, but brood‐sizes varied significantly. Comparisons of relative frequencies and reproduction of clones over the investigated stations suggest that if reproductive differences influence clonal distributions, it will be through frequency‐dependent reproduction rather than through constant fitness differences in various microhabitats. Even then, the observed reproductive differences are hardly sufficient to be the sole cause of clonal distributions.