Two new species of the Macrobiotus hufelandi complex (Tardigrada: Eutardigrada: Macrobiotidae) from Australia and India, with notes on their phylogenetic position

Abstract

In this paper we describe two new tardigrade species belonging to the Macrobiotus hufelandi complex: Macrobiotus noongaris sp. nov. from Perth, Australia, and Macrobiotus kamilae sp. nov. from Mussoorie, India. Live specimens extracted from moss samples were used to establish laboratory cultures in order to obtain additional animals and eggs needed for their integrative descriptions. These descriptions are based on traditional morphological and morphometric data collected using both light and scanning electron microscopy, which, at the same time, were associated with DNA sequences of four genetic markers, three nuclear (18S rRNA, 28S rRNA and ITS-2) and one mitochondrial (COI). The use of DNA sequences allowed for a more accurate verification of the taxonomic status of M. noongaris sp. nov. and M. kamilae sp. nov as independent species of the hufelandi group. Although they both exhibit typical inverted goblet-shaped processes, they represent a recently discovered clade, which was thought to group species with modified morphology of egg processes. Thus, this contribution expands the definition of the mentioned clade and constitutes another link that will be helpful for future studies on the evolution of the M. hufelandi complex.

Integrative Descriptions of Two New Tardigrade Species along with the New Record of Mesobiotus skorackii Kaczmarek et al., 2018 from Canada

“…Mac. joannae Pilato and Binda, 1983, known only from the type locality in Australia (Pilato and Binda [69]; see also comments in Nowak and Stec [68]), by lower average pt of stylet support insertion points (80.2 in the new species vs. 81.9 in Mac. joannae), smaller size of macroplacoid 1 and microplacoid (8.2-16.0 and 2.4-4.9 µm, respectively, in the new species vs. 19.3 and 6.4 µm, respectively, in Mac.…”

Macrobiotus rebecchii sp. nov.: A New Limno-Terrestrial and Hermaphroditic Tardigrade from Kyrgyzstan

“…The dried slides were sealed with transparent nail polish and examined under a Leica DMLB light microscope with PCM and a digital camera. Immediately after mounting the specimens in the medium, the slides were checked under PCM for the presence of males and females in the studied population, as the spermatozoa in the testis or ovotestis are visible only for a few hours after mounting [ 12 , 24 ]. To obtain clean and extended specimens for SEM, tardigrades were processed according to the protocol by Stec et al [ 23 ].…”

Reaching the Monophyly: Re-Evaluation of the Enigmatic Species Tenuibiotus hyperonyx (Maucci, 1983) and the Genus Tenuibiotus (Eutardigrada)

“…Slides were examined under an Olympus BX53 light microscope with phase contrast (PCM), associated with an Olympus DP74 digital camera. Immediately after mounting the specimens in the medium, slides were checked under PCM for the presence of males and females in the studied population [61,80]. Specimens for the SEM analysis were processed according to the protocol by Stec et al [49].…”