Turbellarian taxonomic database

Abstract / Notes

"The acotylean polyclads are characterized by the absence of a ventral sucker located posteriorly to the
female gonopore. These flatworms are mostly marine, benthic or pelagic, except by two species, one freshwater
Limnostylochus borneensis and other semi-terrestrial Myoramyxa pardalota. Oaxaca is a state located in the
southern Mexican Pacific, where only three acotyleans species have been formally recorded until now. After
sampling littoral to sublittoral zones, a total of 34 specimens were collected and fixed in frozen formalin.
Some specimens were stained with Mayer's carmalum and hematoxylin and cleared in methyl salicylate for whole
mounts; the portion containing the reproductive structures of other specimens were dissected and
histologically processed in sagittal and frontal sections. Four species were identified as belonging to four
genera and three families. The new genus Bisacculosuteri gen. nov. is established, close to the genus Itannia,
but lacking double ventral suckers placed on both sides of the female gonopore. Two species are new to
science: Bisacculosuteri marcelae sp. nov., characterized by a highly branched central pharynx, prominent
seminal vesicle, a penis papilla with stylet, paired strongly muscularized uterine sac and uterine vesicles;
and Paraplanocera oligoglenoides sp. nov., with translucent body, light brown pigmentation and black dots
distributed in the pharyngeal and reproductive regions, and an oval cirrus sac with intramuscular surrounding
hollow spaces and armored with spines and conspicuous teeth. The third species is Euplanoida cf. pacificola
that could not be determined as the nominal species, due to ambiguity in its description. The fourth species,
Bivesiculoplana lamothei, was previously described from the region and now is recorded in new localities and
hosts from Oaxaca."

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