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Spadella kappae sp. nov. Spadella kappae Schmidt-Rhaesa & Vieler, 2018: 257���265, figs 1���5 [unavailable]. Type material. Holotype: adult specimen, on SEM stub, ZMH C861. Paratypes: 3 specimens on SEM stub, ZMH C859; 5 specimens on SEM stub, ZMH C860; 1 specimen on SEM stub, ZMH C862, 1 specimen on microscopical slide, ZMH C863. All specimens from same locations: ���amphioxus-sand��� at 20 m depth (48��43.3450��N, 003��50.802��W) and ���trou aux Raies��� at 70 m depth (48��49.472��N, 004��09.733��W), both off the Marine Biological Station in Roscoff. Diagnosis. Length 1.7 to 3.5 mm. Septum at approximately 50% of total body length. Paired and completely rayed lateral fins and unpaired tail fin, lateral fins continuing ventral to seminal vesicles. Collarette tissue abundant. 11 to 12 grasping spines per side. Fine structure with ridges and denticles. 3 to 4 teeth in anterior region of vestibulum, each tooth with four longitudinal serrated ridges and tip with four peaks. Ventral ganglion 40.2���63.1% of trunk length. Dorsal and lateral side covered by groups of cilia, adhesive papillae on ventral side. Kidney-shaped corona ciliata. Intestine without diverticula. Testes are not visible. Ovary 60% of trunk length, receptacula seminis present, paired seminal vesicles oval, in the last third of tail. Etymology. Named kappae, after Helga Kapp, to acknowledge her contributions to the study of Chaetognatha and for giving valuable advice for the description of this species. Remarks. A full description and figures of Spadella kappae is given by Schmidt-Rhaesa & Vieler (2018)., Published as part of Schmidt-Rhaesa, Andreas & Vieler, Vera, 2020, Validation of Spadella kappae Schmidt-Rhaesa & Vieler, a small benthic chaetognath from Roscoff, France (Chaetognatha), pp. 300 in Zootaxa 4759 (2) on page 300, DOI: 10.11646/zootaxa.4759.2.12, http://zenodo.org/record/3737391

Schmidt-Rhaesa & Vieler (2018) described a new species of benthic chaetognath, Spadella kappae, collected by meiofaunal sampling near Roscoff, France. Although the description and figures presented by Schmidt-Rhaesa & Vieler (2018) fully characterize the new species, the journal issue in which the description appeared was published online-only, with no print version, and the article in which the new name appeared did not include a ZooBank registration number for the article (LSID), required for validation of new species names in electronic-only publications (ICZN 2012). As a result, the name Spadella kappae Schmidt-Rhaesa & Vieler, 2018, as published in Cahiers de Biologie Marine 59: 257–265, is not available according the International Code of Zoological Nomenclature, hereafter, the Code (ICZN 1999, 2012). Therefore, the present note serves to validate the name Spadella kappae by fulfilling Code conditions for nomenclatural availability. The date and authorship of the specific name, accordingly, are those of this note, not Schmidt-Rhaesa & Vieler (2018).

Schmidt-Rhaesa, Andreas, Vieler, Vera (2020): Validation of Spadella kappae Schmidt-Rhaesa & Vieler, a small benthic chaetognath from Roscoff, France (Chaetognatha). Zootaxa 4759 (2): 300-300, DOI: https://doi.org/10.11646/zootaxa.4759.2.12

A new species, Chordodes colchis, is described from several locations in Georgia. The species resembles some other Chorodes species, especially C. anthophorus, which has also been described from Georgia, but differs in conspicuous details. The new species possesses prominent thorn areoles, which were not described in C. anthophorus. The new species is the seventh species known from Georgia.

Only four species of freshwater Nematomorpha (Gordiida) and one undetermined Gordius sp. are known from New Zealand. During recent surveys in the South Island we discovered a new species belonging to the genus Gordionus, a genus new to New Zealand. Scanning electron microscopic observations of seven collected specimens revealed that the species is clearly morphologically distinct from all other members of the genus and is characterised by the presence of an extensive row of large bristles on the ventral side of the posterior end in males. This row is much larger than in any known Gordionus species. Analysis of the mitochondrial CO1 gene and of the nuclear 18S rRNA gene showed that the new Gordionus specimens form a monophyletic clade, but with partly extensive internal genetic difference. This indicates that cryptic species might be present, for although there are minor variations in cuticular areoles, other morphological characters indicate little difference between specimens.LSID urn:lsid:zooban...

Two new species of the genus Tubiluchus (Priapulida) are described from marine sediments in Japan. Both species were found to differ in a number of fine structural characters (the pharyngeal teeth, the buccal tube and the scalids) from previously described species. Tubiluchus soyoae n.sp. differs from other species by the structure of the male genital region, a size-increase of scalids from anterior to posterior and the structure of scalids in the first ring. There are no anterior buccal papillae. Pharyngeal teeth possess the usual two combs and those of the anterior ring possess an additional third comb which is unknown from other species. Intraspecific variability of 18S rDNA and COI sequences was low (0.17% and 0.76%, respectively), but interspecific variability of 18S rDNA was 1.43–3.32% within the genus. Tubiluchus pardosi n.sp. differs from other species by the fine structure of scalids, in particular the division into a basal part with smooth cuticle and a distal part with fine cuticular hairs. Further differences are in the structure of the pharyngeal teeth in the anterior ring, the transition between pectinate teeth and fimbrillae and in the structure of the buccal tube.

Nematodes are a large and diverse monophyletic taxon with about 20,000 known species. They are part of the taxon Ecdysozoa, some of which possess a characteristic type of brain called the cycloneuralian brain. Because animals with a cycloneuralian brain likely are not a monophyletic group, it is important to describe and understand the structure of cyloneuralian brains and associated nervous system structures. With respect to nematodes, most studies focus on model organisms, such as Caenorhabditis elegans and immunohistochemical data in general, are rare. To expand the knowledge, we investigated two species of the family Plectida, Plectus acuminatus and Plectus aquatilis by immunohistochemical experiments combined with confocal laser-scanning microscopy. In comparison with C. elegans and further nematodes, our results reveal a conserved architecture of the nervous system and several structures can be homologized with known counterparts. Nevertheless, in detail, some striking differences can be demonstrated, which become visible in the arrangement of longitudinal and transverse neurites as well as in specialized neurons, such as the neurosecretory motor neurons within the pharynx. Compared to C. elegans, the branching pattern of these neurons in Plectus spp. is more complex. Overall, there are indications that the nervous system among nematodes is more diverse in structure than originally expected and further studies on taxonomically basal, free-living nematodes needs to be in focus on future investigations.