Table 7. Life span, selfing reproduction capacity and egg-cluster laying characteristics of isolatelly-maintained Lymnaea schirazensis specimens of four populations from different geographical origins, experimentally followed up from the day of their individual isolation immediately after hatching.
| POPULATIONS | Snail life span* (days) | Laying period** (days) | Number of clusters laid per snail | Total laying capacity (No. clusters/life span in days) | Laying rate in sexual period (No. clusters/laying period in days) | No. of days in which only one cluster was laid | No. of days in which two clusters were laid | Total non-laying days within laying period | Max. No.of non-laying days between two laying days | Postlaying period*** (days) |
| Tiba, Delengate, Egypt (n = 10 snails) | 102−198 (138.80±33.88) | 51−136 (78.90±26.61) | 23−54 (34.80±10.18) | 0.12−0.45 (0.27±0.11) | 0.21−0.72 (0.48±0.18) | 23−46 (32.00±7.00) | 0−4 (1.50±1.65) | 23−101 (46.00±28.00) | 2−36 (12.00±12.00) | 6−37 (17.00±11.00) |
| Albufera, Valencia Spain (n = 10 snails) | 157−205 (181.40±16.59) | 100−161 (133.70±20.20) | 38−70 (51.50±12.62) | 0.20−0.43 (0.29±0.07) | 0.26−0.60 (0.40±0.12) | 37−66 (48.00±10.00) | 0−7 (1.90±2.02) | 49−112 (84.00±23.00) | 6−34 (17.00±11.00) | 1−33 (12.00±10.00) |
| Esc.Obregon, Trinidad T. Mexico (n = 10 snails) | 88−139 (117.80±18.60) | 45−90 (65.00±16.15) | 9−35 (19.90±7.69) | 0.10−0.25 (0.17±0.04) | 0.20−0.42 (0.30±0.08) | 9−35 (19.90±7.69) | 0−0 (0±0) | 34−69 (45.00±12.00) | 6−24 (15.00±7.00) | 3−37 (18.00±11.00) |
| Jiutepec, Morelos Mexico (n = 10 snails) | 75−125 (94.80±16.02) | 39−69 (48.50±8.61) | 13−26 (16.20±3.65) | 0.13−0.22 (0.17±0.02) | 0.29−0.38 (0.33±0.03) | 13−26 (16.00±4.00) | 0−1 (0.20±0.42) | 25−43 (33.00±5.00) | 5−11 (8.00±2.00) | 7–49 (17.00±12.00) |
| TOTAL (n = 40 snails) | 75−205 (133.20±38.86) | 39−161 (81.53±37.21) | 9−70 (30.60±16.63) | 0.10−0.45 (0.22±0.09) | 0.20−0.72 (0.38±0.13) | 9−66 (28.8±14.5) | 0−7 (0.90±1.52) | 23−112 (51.83±27.00) | 2−36 (12.90±9.06) | 1−49 (16.03±11.01) |
Range include minimum and maximum extremes, with mean±standard deviation SD in parentheses. n = number of specimens measured; * life span = days elapsed from day of hatching up to day of death; ** laying period = days of sexual activity elapsed from first to last days when clusters were laid by the snail specimen, inclusive; *** postlaying period = time elapsed between last laying day and death.