Efeito da densidade populacional sobre o crescimento e a reprodução de Bradybaena similaris (Férussac, 1821) (Mollusca, Xanthonychidae) e Leptinaria unilamellata (dOrbigny, 1835) (Mollusca, Subulinidae)

RESUMO

For this study, 300 specimens of both species were divided in five different groups G1 n=10, G2 n=20, G3 n=30; G4 n=40 and G5 n=50. The length of the shell was measured every 15 days for 180 days. The eggs and young were retired and counted daily. In Bradybaena similaris, the shells average length (mm) was G1 13,32; G2 11,96; G3 11,25; G4 11,66 and G5 10,18. The average number of eggs per group in B. similaris was G1 133,3; G2 63,17; G3 39,03; G4 24,07 and G5 25,44. In Leptinaria unilamellata, the shells average lenght (mm) was G1 17,06; G2 18,44; G3 14,8; G4 12,2 and G5 14,22. The average number of offspring per group in L. unilamellata was G1 24,75; G2 23,55; G3 16,13; G4 10,31 and G5 20,69. The population density influence the growth and the reproduction in B. similaris, and it just influence the growth in L. unilamellata.