Reflections on the genus Amaga Ogren and Kawakatsu 1990, and description of a new genus of land planarian (Platyhelminthes: Tricladida: Geoplanidae)

Amaga amagensis, the type species of the genus Amaga, and Amaga bogotensis are re-described. Detailed analysis of the morphology of A. amagensis revealed important taxonomic features, such as testes located dorsally to the supraintestinal parenchymal muscular layer, and secretory accumulations opening through the lateral margins of the body. These characters, as well as other morphological features, are discussed, culminating in an emendation of the generic diagnosis of Amaga. Amaga bogotensis exhibits a characteristic set of morphological features, namely an eversible penis, a male atrium lined with large musculosecretory papillae, and independent muscular coats around both male and female atrium. Therefore, a new genus is proposed for this species.     

A new higher classification of planarian flatworms (Platyhelminthes,Tricladida)

This paper presents a revised classification for the higher taxa within the Tricladida. A historical sketch is provided of the higher classificatory systems of triclad flatworms. As far as possible, the new classification is based on published phylogenetic studies. A phylogenetic tree generalizing currently available hypotheses on the higher-taxon relationships of the Tricladida forms the backbone of the new classification. There is no longer any room in formal classifications for the taxon names Terricola and Paludicola, previously used to indicate the suborders of freshwater and land planarians, respectively. It is a consequence of the new classification that the taxonomic rank of the terrestrial planarians is now at the level of family. A new diagnosis of this family is provided. The taxon name Continenticola denotes a monophyletic group consisting of the freshwater planarians and the terrestrial planarians. At this stage it is difficult to find unequivocal morphological apomorphies enabling a diagnosis for the Continenticola.     

A new predatory flatworm (Platyhelminthes,Polycladida) from Botany Bay,New South Wales,Australia

A new species of Stylochidae flatworm Imogine lateotentare is described from Botany Bay, eastern New South Wales, Australia. This flatworm is distinguished from other species in the same genus mainly by having small, transparent and inconspicuous tentacles, densely packed purplish pink flecks at the posterior of the dorsal surface, distinctive purplish red colour gonopores and continuous bands of numerous frontal and cerebral eyes. Feeding and reproductive behaviour in the laboratory are described. This flatworm was found closely associated with the barnacle Balanus variegatus (Darwin, 1854) on which it fed by extending its pharynx over the barnacle opercular and sucking out the flesh but ejecting the cirri. It consumed one Balanus variegatus in a 14‐day observation period and it was observed feeding exclusively at night.     

Two new Pleioplana species (Platyhelminthes,Polycladida, Acotylea) from Turkey

Two new species of flatworms, Pleioplana bosphorensis sp. nov. and Pleioplana Okusi sp. nov., Acotylea, Polycladida, are described from the shallow rocky shores of the Turkish Straits System, northwestern Turkey. Both species are characterized by a prostatic vesicle of atomata-type, stylet and Lang's vesicle. Pleioplana bosphorensis possesses a body of fleshy consistency and without tentacles, with spermiducal bulbs; elongated seminal vesicle and rounded prostatic vesicle with four tubular chambers and a conical, strong, large and straight stylet. Pleioplana Okusi has a translucent body, tentacular knobs, large seminal vesicle, elongated prostatic vesicle with six tubular chambers, and a long slender slightly curved stylet.     

A redescription of the type specimen of Crotonia (= Acronothrus) obtecta (O. Pickard-Cambridge, 1875), (Acari,Cryptostigmata) and a discussion of its taxonomic relationships

Summary

The holotype of Crotonia (= Westwoodia) obtecta (O. Pickard-Cambridge, 1875) has been cleaned and is redescribed. Study indicates that Crotonia Thorell, 1876 is a senior synonym of Acronothrus Berlese, 1916, and that the family Crotoniidae Thorell, 1876 is a senior synonym of the Holonothridae Wallwork, 1963     

Taxonomic and biological observations on the tiger flatworm,Maritigrella crozieri (Hyman, 1939), new combination (Platyhelminthes,Polycladida, Euryleptidae) from Florida waters

The tiger flatworm, Maritigrella crozieri (Hyman, 1939) (Platyhelminthes, Polycladida, Cotylea) new combination, is redescribed from eastern Florida and the Florida Keys. This marine flatworm is one of the most common polyclads within warm temperate to tropical west Atlantic, yet it has been misidentified consistently as a pseudocerotid. Animals were kept alive in the laboratory for 3 weeks for biological observations. Findings indicated that these euryleptids employ hypodermic insemination, with multiple copulations occurring over several days. Sperm was transferred in sperm bundles bilaterally with little apparent damage to the epidermis of the copulating worms. Copulation sessions were variable and lasted an average of 15.4 min. In situ and laboratory observations indicated that M. crozieri fed exclusively on the mangrove ascidian Ecteinascidia turbinata Herdman, 1880, an individual consuming one prey zooid in an average of 17 min and an average of 19 zooids over 24h.     

A new stylochid flatworm (Platyhelminthes,Polycladida) from Victoria,Australia and observations on its biology

There are only four polyclad flatworms currently known from temperate waters of Victoria, Australia, although these turbellarians are common inhabitants of rocky shores. A new stylochid flatworm, Stylochus pygmaeus sp. nov. (Platyhelminthes, Polycladida) or oyster leech is described here from Port Philip Bay, Victoria. This flatworm was observed feeding on three species of barnacles by extending its pharynx over its prey and extruding copious amounts of mucus. Worms also preferred to prey on larger‐sized barnacles regardless of the species. Further observations indicated that these worms deposited eggs at night inside empty barnacle shells. Each eggmass was brooded for several days with the worms only moving off to feed. Each egg capsule contained multiple embryos and after 5 or 6 days, positively photo‐tactic, four‐lobed Götte's larvae emerged. Larvae metamorphosed to juvenile flatworms 1–2 weeks post‐hatching but failed to settle and survive.     

Contribution to the knowledge of the genus Pseudomonocelis Meixner, 1943 (Rhabditophora: Proseriata)

A new species of the genus Pseudomonocelis (P. caribbea sp. n.) is described. It is distinguished from congenerics by shape and size of the copulatory organ and relative positions of mouth and genital openings. It is the first species of the genus found in America. Sampling in east Africa (Zanzibar island) revealed two species, attributed to P. pardii and, tentatively, to P. cavernicola, both originally described from Somaliland. Morphological differences between Tanzanian and Somali specimens are reported. The Mediterranean P. ophiocephala, based on extensive morphological and karyological survey of 13 populations, is interpreted as constituting at least two sibling species, distinguishable solely on the basis of karyotype. Results support the notion that the present perception of the contribution of interstitial Rhabditophora to marine biodiversity may be unrepresentative.     

Five new Polycladida (Platyhelminthes: Acotylea) species from the Aegean Sea with remarks on the prostatic structures

Five species of polyclads, Imogine melihertani sp. nov., Pseudoplanocera izmirensis gen. et sp. nov., Izmira cinari gen. et sp. nov., Izmira turkeyi sp. nov. and Pseudodiscocelis aegeanensis gen. et. sp. nov., were collected in Izmir Bay, Turkey, Aegean Sea. I. melihertani is characterized by an anchor-shaped seminal vesicle, penis papilla, and ciliated male and female atria. P. izmirensis possesses spermiducal bulbs, a free prostatic vesicle, cirrus bulb, armed cirrus and Lang's vesicle. The genus Izmira is established based on the presence of a penis rod, true seminal vesicle, an interpolated prostatic vesicle of atomata-type and vagina bulbosa. Izmira cinari has an elongated body; a pointed penis and the oviducts enter the vagina bulbosa separately. Izmira turkeyi is characterized by an oval body, rod-shaped penis and the oviducts join before entering the vagina. Pseudodiscocelis is characterized by prostatoid organs, a lobed penis and ciliated and glandular cells in the male antrum.