Two new species and the molecular phylogeny of eight species of Macrostomum (Platyhelminthes: Macrostomorpha) from southern China

Abstract

Two new species of Macrostomum (Platyhelminthes: Macrostomorpha), M. shiyanensis n. sp. and M. lankouensis n. sp. are described from Shiyan Reservoir and Lankou Town. Morphological characteristics of the penis stylets and sperm, as well as the phylogenetic analysis using concatenated sequences of 18S and 28S rDNA genes support the establishment of these two new species and indicate that they are closely related to M. sinensis and M. heyuanensis described from different regions of Guangdong province. Finally, the progress of molecular phylogenetics of Macrostomum worldwide is also discussed.

Large-scale phylogenomics of the genus Macrostomum (Platyhelminthes) reveals cryptic diversity and novel sexual traits

“…The comparison of 28S rRNA sequences has revealed that Macrostomum zhaoqingensis Lin & Wang, 2017 (Lin et al 2017b) is sister to Macrostomum inductum Kolasa, 1971 (Kolasa 1971) and the haplotype analysis closely clusters both species (see Fig. A19 in SI Species delimitation), suggesting that M. zhaoqingensis could potentially represent a re-description of M. inductum .…”

“…The comparison of 28S rRNA sequences has revealed that Macrostomum zhaoqingensis Lin & Wang, 2017(Lin et al 2017b) is sister to Macrostomum inductum Kolasa, 1971(Kolasa 1971 and the haplotype analysis…”

“…Species without available transcriptomes that were included in C-IQ-TREE based on a 28S rRNA fragment are indicated with grey branches. Stylet and sperm are drawn based on our live observations, except for species with underlined names, which were redrawn based on the species descriptions ( M. acus, M. obtusa and M. sinensis from Wang 2005; M. heyuanensis and M. bicaudatum from Sun et al 2015; M. chongqingensis and M. zhaoqingensis from Lin et al 2017a; M. shiyanensis and M. lankouensis from Lin et al 2017b; M. shenzhenensis and M. qiaochengensis from Wang et al 2017; and M. spiriger and M. shenda from Xin et al 2019). Note that the stylet of M .…”

Three new species of Macrostomum (Platyhelminthes, Macrostomorpha) from China and Australia, with notes on taxonomy and phylogenetics

“…Seventy years later, our laboratory reported a second Macrostomum species, Macrostomum xiamense Wang & Luo, 2004. Since then, 22 species of Macrostomum have been reported from China, of which 21 species were newly described, 13 from freshwater and eight from brackish environments ( Lin et al 2017a ; Xin et al 2019 ; Zhang et al 2021 ). China is likely to have a high richness and diversity of Macrostomum species, since 14 new species were reported in the last five years from south China alone, mainly in Guangdong Province.…”

A taxonomic review and revisions of Microstomidae (Platyhelminthes: Macrostomorpha)

“…lineare ). Taken together, it is unsurprising that while there has been some recent studies of species diversity within Macrostomorpha in general (e.g., [7, 12–17]), taxonomic research within Microstomidae from even the last 50 years has been restricted to a very few articles [4, 18–21].…”