Macrobiotus polypiformis sp. nov., a new tardigrade (Macrobiotidae; hufelandi group) from the Ecuadorian Pacific coast, with remarks on the claw abnormalities in eutardigrades

Abstract

Abstract. From a moss sample collected in the Manabí Province in Ecuador, we extracted 96 specimens of a new species of eutardigrade. No eggs were found. In order to obtain eggs, an in vitro culture was prepared. In total, 136 specimens (including ten simplex), one exuvia and 44 eggs (including two with embryos) of the new species were obtained. In addition to the traditional taxonomic description with morphometrics, light and scanning microscopy imaging, we also provide nucleotide sequences of three nuclear (18S rRNA, 28S rRNA, ITS-2) and one mitochondrial (COI) DNA fragments of the new species. Macrobiotus polypiformis sp. nov. belongs to the hufelandi group and is most similar to Ma. paulinae Stec, Smolak, Kaczmarek & Michalczyk, 2015, but differs from it mainly by the lack of dorso-lateral patches of granulation on the cuticle, egg processes with longer and more numerous filaments and in some morphometric characters of both eggs and adults. Moreover, we provide a short discussion on the modifications/abnormalities of the claws in eutardigrades and the possible consequences on the taxonomic status of Mesobiotus armatus (Pilato & Binda, 1996), suggesting its consideration as species inquirenda (with uncertain taxonomic status).

Integrative description of Macrobiotus canaricus sp. nov. with notes on M. recens (Eutardigrada: Macrobiotidae)

“…recens are given in Supplementary Materials (SM.2). The DNA Guidetti et al, 2013KC193575-6 Guidetti et al (2013 M. macrocalix FJ176203-07, FJ176208-17, HQ876571, MH057767 Cesari et al (2009), Bertolani et al (2011a this study M. papei Stec et al, 2018MH057763 Stec et al (2018d M. paulinae Stec et al, 2015KT951668 Stec et al (2015 M. polypiformis Roszkowska et al, 2017KX810011-2 Roszkowska et al (2017 M. sandrae HQ876566-67, HQ876569-70, HQ876562-73, HQ876574-83 Bertolani et al (2011a M. scoticus Stec et al, 2017KY797267 Stec et al (2017b M. shonaicus Stec et al, 2018MG757136-7 Stec et al (2018a M. terminalis JN673960, AY598775 Cesari et al (2011, M. vladimiri Bertolani et al, 2011 HM136931-2, HM136933-4, HQ876568 Bertolani et al (2011aBertolani et al ( , 2011b …”

“…• 18S rRNA: 0.5-3.7% (2.0% on average), being most similar to two undetermined species of the M. hufelandi group from Spain (FJ435738-9) and to M. macrocalix from Poland (MH063926) and the least similar to M. polypiformis Roszkowska et al, 2017 …”

An integrative description of Macrobiotus shonaicus sp. nov. (Tardigrada: Macrobiotidae) from Japan with notes on its phylogenetic position within the hufelandi group

“…M . polypiformis , reported only from the type locality (Ecuador) [ 12 ] by the longer first macroplacoid (7.8–14.9 μm [ pt = 23 . 5 – 35 .…”

“…The integrative description and species delineation involved morphological and morphometric data obtained using phase contrast light microscopy (PCM) and scanning electron microscopy (SEM) as well as molecular data in the form of DNA sequences for four molecular markers (nuclear: 18S rRNA, 28S rRNA, ITS-2, and mitochondrial COI). The new species belongs to the persimilis subgroup (with a solid egg surface between processes), but it has modified egg processes with some teeth of terminal discs elongated to flexible filaments, such as those found in two other recently described species: Macrobiotus paulinae Stec, Smolak, Kaczmarek & Michalczyk, 2015 [ 11 ] from Africa and Macrobiotus polypiformis Roszkowska, Ostrowska, Stec, Janko & Kaczmarek, 2017 [ 12 ] from South America.…”

An integrative description of Macrobiotus hannae sp. nov. (Tardigrada: Eutardigrada: Macrobiotidae: hufelandi group) from Poland

“…The ranges of uncorrected genetic p-distances between the new species and species of the Macrobiotus hufelandi complex for which sequences are available from GenBank are as follows (from the most to the least conservative): • 18S rRNA: 0.0%-4.5% (2.4% on average), with the identical sequence being "M. joannae" from Italy (HQ604974-5) and the least similar being M. polypiformis Roszkowska et al, 2017 from Ecuador (KX810008); • 28S rRNA: 3.9%-12.5% (7.6% on average), with the most similar being an undetermined M. hufelandi group species from Spain (FJ435751, FJ435754-5) and the least similar being M. polypiformis from Ecuador (KX810009); • COI: 17.9%-26.0% (19.9% on average), with the most similar being M. sandrae Bertolani and Rebecchi, 1993 from Germany (HQ876577-9 and HQ876581) and the least similar being M. polypiformis from Ecuador (KX810012).…”