Macrobiotus noongaris Coughlan & Stec 2019, sp. nov.
Creators: name: Coughlan, Kyle
name: Stec, Daniel
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Tardigrada
Eutardigrada
Parachela
Macrobiotidae
Macrobiotus
Macrobiotus noongaris

description: Macrobiotus noongaris sp. nov.
urn:lsid:zoobank.org:act: A7BF7FF6-451F-4382-A842-CAC1EF51E6B8
Figs 1–7
Etymology
The name refers to the indigenous Australians who live in the region where the new species was found. These are the Noongar peoples, 14 different but related language groups that occupied these lands before western settlement, including the modern city of Perth where the sample was collected. In their languages, the term Noongar means ‘a person of the southwest of Western Australia’.
Material examined
86 animals (including 31 simplex) and 57 eggs. Specimens mounted on microscope slides in Hoyer’s medium (72 animals + 47 eggs), fixed on SEM stubs (10+10) and processed for DNA sequencing (4+0).
Holotype AUSTRALIA – Western Australia • ♀; Perth, Kings Park; 31°57′30″ S, 115°350′09″ E; 46 m a.s.l.; moss on soil in an urban park; IZiBB AU.031.12.
Paratypes AUSTRALIA – Western Australia • 62 paratypes; same collection data as for holotype; IZiBB AU.031.06 to AU.031.14 • 32 eggs; same collection data as for holotype; IZiBB AU.031.02–05.
Description
Animals (measurements and statistics in Table 2)
Body transparent in juveniles and white in adults but transparent after fixation in Hoyer’s medium (Fig. 1A). Eyes present in live animals as well as in specimens mounted in Hoyer’s medium. Small round and oval cuticular pores (0.3–0.8 μm in diameter), visible under both PCM and SEM, scattered randomly on entire body (Fig. 1 B–C). Granulation present on all legs (Fig. 2 A–F). A patch of clearly visible granulation present on external surface of legs I–III (Fig. 2 A–B).A cuticular bulge/fold (pulvinus) present on internal surface of legs I–III, with a faint cuticular fold covered with faint granulation and paired muscles attachments just above the claws (Fig. 2 C–D). Both structures are visible only if legs are fully extended and properly oriented on slide (particularly in the case of the pulvinus and cuticular fold). Granulation on legs IV always clearly visible and consists of a single large granulation patch on each leg (Fig. 2 E–F).
Claws stout, of hufelandi type (Fig. 3 A–D). Primary branches with distinct accessory points, a common tract, and with an evident stalk connecting claw to lunula (Fig. 3 A–D). Lunulae I–III smooth (Fig. 3A, C), whereas lunulae IV clearly dentate (Fig. 3B, D). Cuticular bars under claws absent. Double muscle attachments faintly marked under PCM but clearly visible under SEM (Fig. 3A, C).
Mouth antero-ventral followed by ten peribuccal lamellae and a circular sensory lobe (Figs 4A, 5A). Bucco-pharyngeal apparatus of Macrobiotus type (Fig. 4A). Under PCM, oral cavity armature of the patagonicus type, i.e., with only 2 nd and 3 rd bands of teeth visible (Fig. 4 B–C). However, in SEM all three bands of teeth visible, with first band being situated at base of peribuccal lamellae and composed of a single row of small fused cone-shaped teeth connected to form a continuous, slightly serrated ring ridge around oral cavity (Fig. 5 B–C). Second band of teeth situated between ring fold and third band of teeth and comprises 3–6 rows of small cone-shaped teeth (Figs 4 B–C, 5B–C). Teeth of third band located within posterior portion of oral cavity, between second band of teeth and buccal tube opening (Figs 4 B–C, 5B–C). Third band of teeth discontinuous and divided into dorsal and ventral portions. Under PCM, dorsal teeth appear as three distinct transverse ridges, whereas ventral teeth appear as two separate lateral transverse ridges and a median tooth (Fig. 4 B–C). In SEM, both dorsal and ventral teeth also clearly distinct (Fig. 5 B–C). Under SEM, margins of medio-dorsal tooth slightly serrated (Fig. 5B), whereas the medio-ventral tooth slightly anterior to lateral teeth (Fig. 5C). Pharyngeal bulb spherical, with triangular apophyses, two rod-shaped macroplacoids and a small triangular microplacoid (Fig. 4A, D–E). Macroplacoid length sequence 2 <1. First macroplacoid exhibits central constriction, whereas second macroplacoid sub-terminally constricted (Fig. 4A, D–E).
Eggs (measurements and statistics in Table 3)
Laid freely, white, spherical or slightly ovoid (Fig. 6A). Surface between processes is of the hufelandi type, i.e., covered with a reticulum (Figs 6E, 7 B–D, F). Meshes of reticulum small (0.1–0.6 µm) and rounded, regular in size and with blurred rims in PCM (Fig. 6E), irregular in size and with thick borders in SEM (meshes in SEM appear as pores; Figs 7 B–D, F). Interbasal meshes larger than peribasal meshes, but peribasal meshes do not form rings around process bases (Figs 6E, 7 B–D, F). Eggs have 22–30 processes on circumference, 26 on average (Fig. 6A). Processes are of inverted goblet shape, with slightly concave trunks and concave terminal discs (Figs 6 C–E, 7B–E). Terminal discs are round and strongly serrated (Fig. 7 C–E). Each terminal disc has a distinct concave central area which may contain some scattered granulation within, which is also always present on the margin (visible only under SEM; Fig. 7 C–E).
Reproduction
The new species is dioecious. No spermathecae filled with sperm have been found in gravid females on the freshly prepared slides. However, the testis in males, filled with spermatozoa, is clearly visible under PCM up to 24 hours after mounting in Hoyer’s medium (Fig. 6F). The new species does not exhibit male secondary sexual dimorphism traits such as lateral gibbosities on legs IV.
DNA sequences
We obtained sequences for all four of the above mentioned DNA markers. All sequenced fragments were represented by single haplotypes except the ITS-2, in which two distinct haplotypes were present:
The 18S rRNA sequence (GenBank: MK737069), 1010 bp long.
The 28S rRNA sequence (GenBank: MK737063), 786 bp long.
The ITS-2 haplotype 1 sequence (GenBank: MK737065), 418 bp long.
The ITS-2 haplotype 2 sequence (GenBank: MK737066), 418 bp long.
The COI sequence (GenBank: MK737919), 658 bp long.
description: Published as part of Coughlan, Kyle & Stec, Daniel, 2019, Two new species of the Macrobiotus hufelandi complex (Tardigrada: Eutardigrada: Macrobiotidae) from Australia and India, with notes on their phylogenetic position, pp. 1-38 in European Journal of Taxonomy 573 on pages 6-15, DOI: 10.5852/ejt.2019.573, http://zenodo.org/record/3526912