Phylogeny and systematic revision of the family Pseudokeronopsidae (Protista, Ciliophora, Hypotricha), with description of a new estuarine species of Pseudokeronopsis

Abstract

Chen, X., Clamp, J. C. & Song, W. (2011). Phylogeny and systematic revision of the family Pseudokeronopsidae (Protista, Ciliophora, Hypotricha), with description of a new estuarine species of Pseudokeronopsis. —Zoologica Scripta, 40, 659–671. The family Pseudokeronopsidae is a taxon of hypotrich ciliates with a history of uncertainty regarding its systematic and phylogenetic relationships to other members of the order Urostylida. Phylogenetic analyses of pseudokeronopsids were made using all available molecular and morphological information, and the patterns of morphogenesis of the group were reinvestigated. Results clearly demonstrated that the genera Thigmokeronopsis and Apokeronopsis are not confamilial with Pseudokeronopsis and Nothoholosticha but, instead, must be transferred to the family Urostylidae. A new estuarine species, Pseudokeronopsis erythrina sp. n. was discovered and described using a combination of morphological and molecular characters. Species of Pseudokeronopsis are difficult to characterize but can be distinguished from one another by a combination of morphological and morphogenetic characters. Pseudokeronopsis similis is a freshwater species that has significant morphogenetic differences with other members of the genus and may not be congeneric with them.

Description and Phylogeny of Tetrakeronopsis silvanetoi gen. nov., sp. nov. (Hypotricha, Pseudokeronopsidae), a New Benthic Marine Ciliate from Brazil

“…The phylogenetic trees obtained in the present study are generally in agreement with the literature concerning the internal kinships of the core urostyloids [20], [23], [24], [44], including their families and the paraphyly of pseudourostylids, which is recurrent in the literature [22], [23], [40]. In addition, the spreading of Anteholosticha spp.…”

Three-gene based phylogeny of the Urostyloidea (Protista, Ciliophora, Hypotricha), with notes on classification of some core taxa

“…However, the discussion above strongly suggests that Thigmokeronopsis and Apokeronopsis are closely related and clearly separated from the core pseudokeronopsids, and therefore we re-activate the Thigmokeronopsinae Wicklow, 1981 for this taxon. The topologies of the trees suggest that this group is a member of the Urostylidae to which Thigmokeronopsis and Apokeronopsis have been assigned just recently by Chen et al (2011a). According to the SSU-rDNA data, Apourostylopsis sinica , type of Apourostylopsis , is closely related to Thigmokeronopsis and Apokeronopsis (Fig.…”

Phylogenetic framework of the systematically confused Anteholosticha–Holosticha complex (Ciliophora, Hypotrichia) based on multigene analysis

“…For those species that could not be cultured, cells of the target species were isolated from the sample under the stereomicroscope and then were washed several times with sterile filtered marine water. Species identification was based on live observations and protargol-stained specimens (Chen et al, 2011b). General terminology and systematic classification are mainly according to Berger (2006) and Lynn (2008).…”