Schmidtea polychroa ( Schmidt, 1861 ), Schmidt, 1861

Stocchino, Giacinta Angela, 2018, 80 years of research on planarians (Platyhelminthes, Tricladida) from Sardinia, Italy: an annotated checklist, Zootaxa 4532 (4), pp. 539-552: 543

publication ID

https://doi.org/10.11646/zootaxa.4532.4.5

publication LSID

lsid:zoobank.org:pub:807B317B-D883-439F-97B9-B0C0F09D9666

persistent identifier

http://treatment.plazi.org/id/C45EE309-B11C-FFF1-66FB-FF4111F6FD58

treatment provided by

Plazi

scientific name

Schmidtea polychroa ( Schmidt, 1861 )
status

 

Schmidtea polychroa ( Schmidt, 1861)  

Schmidtea polychroa   is distributed mainly in the northern part of the island in large hydrographic basins as well as small rivers ( Fig. 2 View FIGURE 2 ). On the basis of karyological and reproductive characteristics four biotypes (A, B, C, D) have been recognized within the species ( Benazzi, 1957; Benazzi & Benazzi Lentati, 1976).

The first record of S. polychroa   from Sardinia by Benazzi (1957) reported the presence of biotype A, which is amphimictic and diploid (2n = 8; n = 4). Pala and co-workers ( Pala et al., 1980b; Casu et al., 1982; Vacca et al., 1988, 1993) highlighted the widespread distribution of biotype A and found also several populations characterized by triploid (3n = 12; n = 4) and tetraploid chromosome sets (4n = 16; n = 4), corresponding to the gynogenetic, asynaptic biotypes C and D, respectively. Biotype B was never found in Sardinia. Further, a new pentaploid biotype (5n = 20; n = 4) was found in a population from River Temo for which the type of development is unknown ( Casu et al., 1982) ( Fig. 2 View FIGURE 2 ).