[The distribution and possible competition between Melanoides tuberculata and Tarebia granifera (Prosobranchia: Thiaridae) in Lake Hanabanilla, Cuba]. / Distribución y posible competencia entre Melanoides tuberculata y Tarebia granifera (Prosobranchia: Thiaridae) en el lago Hanabanilla, Cuba.

A study was carried out along three years, on distribution and possible competence between the two thiarid species present in Lake Hanabanilla, Cuba: Melanoides tuberculata and Tarebia granifera. Both species presented significant differences as to its abundance within a determined microhabitat, but they could match their densities for the total sampled area. These variations were mainly due to the ratio of juveniles in each species. Interaction was only detected when high abundance values were reached and some limitation resource existed (mainly in the nearest area to the shore). Both thiarids presented a high nest width, but Tarebia granifera was slightly higher; besides, this species was dominant at the end of the study at most of the sampled areas.

[Biomphalaria havanensis and Biomphalaria orbignyi (Pulmonata: Planorbidae). 2 species in synonymy?]. / Biomphalaria havanensis y Biomphalaria orbignyi (Pulmonata: Planorbidae). Dos especies en sinonimia?

Morphometrics differences of 2 species of the genus Biomphalaria in Cuba (B. havanensis and B. orbignyi) were studied. These are potential intermediate hosts of schistosomiasis whose taxonomic location has been discussed. Of the variables measured the following coefficients were compared (length of the sheath of the penis/length of prepuce, caudal distance/cephalic distance, diameter of the shell/width of the shell) with the use of univariate and multivariate tests. Both tests proved that the length of the prepuce is the variable which discriminate best between both groups. These results complement other aspects which advocate for the taxonomic separation of these 2 species of planorbids [correction of plororbis].