Towards a better understanding of deep-sea tardigrade biogeography: numerous new records from the Southern Ocean.

To date, only eight species of marine tardigrades have been recorded from the Southern Ocean. A total of 1210 tardigrade specimens were collected during various marine expeditions with R/V POLARSTERN: ANDEEP-1, ANDEEP-2, ANDEEP-3 and ANDEEP-SYSTCO. The sampled tardigrades belong to five families (Batillipedidae, Coronarctidae, Halechiniscidae, Styraconyxidae and Echiniscoididae), seven genera (Batillipes, Coronarctus, Moebjergarctus, Angursa, Styraconyx, Tholoarctus, Isoechiniscoides) and 15 species (Batillipes wyedeleinorum, Coronarctus dissimilis, Coronarctus tenellus, Coronarctus cf.

Validation of Spadella kappae Schmidt-Rhaesa amp; Vieler, a small benthic chaetognath from Roscoff, France (Chaetognatha).

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).

A New Species of Gordionus (Nematomorpha: Gordiida) from the Rocky Mountains of New Mexico.

The 19 genera within the phylum Nematomorpha contain approximately 350 species. The cosmopolitan genus Gordionus Müller, 1926 contains about 58 species, 6 of which occur in the contiguous United States of America. Recently, 2 new Gordionus species were described from high-altitude streams within the southern Rocky Mountains, near Santa Fe, New Mexico.

A new species of (Phylum Nematomorpha) from terrestrial habitats in North America.

Freshwater hairworms (class Gordiida) are members of the phylum Nematomorpha that use terrestrial arthropods as definitive hosts but reside as free-living adult worms in rivers, lakes, or streams. The genus consists of 90 described species, of which three species were described from freshwater habitats in North America. In this paper we describe a new species of from terrestrial habitats in Oklahoma, Texas, and Louisiana, United States.

New hairworm (Nematomorpha, Gordiida) species described from the Arizona Madrean Sky Islands.

Gordiids, or freshwater hairworms, are members of the phylum Nematomorpha that use terrestrial definitive hosts (arthropods) and live as adults in rivers, lakes, or streams. The genus consists of 18 species, one of which was described from the Nearctic in 1851. More than 150 years later, we are describing a second species from a unique habitat within the Nearctic; the Madrean Sky Island complex.

Nematomorpha from Hong Kong and description of a new species from Malaysia.

We report here for the first time horsehair worms (Nematomorpha) from Hong Kong (China). Most specimens belong to the genus Chordodes, and can be assigned to C. bipilus, C.

On the recovery of horsehair worms, sp. (Nematomorpha: Gordiida) from pork in Shillong, India.

The members of the phylum Nematomorpha, called as horsehair or gordian worms, are the parasites of arthropods and emerge from their host for reproduction and early development in water. There are about 360 species of nematomorphs described till date. Although, horsehair worms are parasites of arthropod species, sporadic cases of their occurrence have also been reported from several other hosts, including man.

Intra- and interspecific genetic diversity of New Zealand hairworms (Nematomorpha).

Hairworms (Nematomorpha) are a little-known group of parasites, and despite having been represented in the taxonomic literature for over a century, the implementation of molecular genetics in studies of hairworm ecology and evolution lags behind that of other parasitic taxa. In this study, we characterize the genetic diversity of the New Zealand nematomorph fauna and test for genetic structure within the most widespread species found. We provide new mitochondrial and nuclear ribosomal sequence data for three previously described species from New Zealand: Gordius paranensis, Parachordodes diblastus and Euchordodes nigromaculatus.

First report of the Gondwana genus from India, with further records of two species (Gordiida, Nematomorpha).

Three horsehair worms (Nematomorpha) are recorded from Nagaland, India. The first species is , which was recently described from Nagaland. The second is Chordodes cf.

Reconstructing the anterior part of the nervous system of Gordius aquaticus (Nematomorpha, cycloneuralia) by a multimethodological approach.

The Nematomorpha (horsehair worms) and Nematoda (round worms) are sister taxa (together Nematoida) and closely related to Scalidophora (Priapulida, Kinorhyncha, Loricifera). To date, all species were assumed to possess a specific brain type, i.e.

New records of Indian Nematomorpha, with the description of a new species from the genus Chordodes.

Chordodes tjorvenae, a new species of horsehair worms is described from Mizoram, Northeast India. The species is distinct from all other known species by a unique combination of cuticular charatcers. In addition, the occurrence of the genus Acutogordius, particularly A.

Nematomorpha from the Philippines, with description of two new species.

With the exception of one species, no horsehair worms (Nematomorpha) were known to date from the Philippines. We report here several records, almost all from Panay Island. Two species, Gordius jorriti and Acutogordius finni, are described as new species.

Gordius gonzalezi, a new species of horsehair worms (Nematomorpha) from Spain.

A new species, Gordius gonzalezi, is described from the Iberian Peninsula, from the Sierra de los Tormantos in Central Spain. Characteristic for the species is the presence of multiple short spines on the cuticle, not present in this form in any other Gordius species. Additionally, two further specimens are reported, which could not be determined to species level.

Using Gordiid cysts to discover the hidden diversity, potential distribution, and new species of Gordiids (Phylum Nematomorpha).

In this study, we sampled aquatic snails for the presence of hairworm cysts from 46 streams in Payne County, Oklahoma. Gordiid cysts were found at 70 % (32/46) of sites examined. Based on cyst morphology, we were able to identify three morphological types of gordiid cysts, including Paragordius, Gordius, and Chordodes/Neochordodes.

Chordodes ferox, a new record of horsehair worms (Nematomorpha, Gordiida) from South Africa.

Three females and one male specimen of a previously unconfirmed species of horsehair worms (Nematomorpha) from South Africa are described using Scanning Electron Microscopy. The females correspond to the description of Chordodes ferox Camerano, 1897, a species previously described from the Democratic Republic of the Congo (Congo-Kinshasa) and an adjacent, not further specified region of the Republic of Congo (Congo-Brazzaville). Characteristic is the presence of enlarged and elevated simple areoles around the base of a thorn areole, in combination with further cuticular characters.

A new species of Cephalodasys (Gastrotricha, Macrodasyida) from the Caribbean Sea with a determination key to species of the genus.

A new marine gastrotrich species of the genus Cephalodasys is described from shallow sublittoral coralline sand sampled between Lee Stocking Island and Norman's Pond Cay (Exuma Cays), Bahamas. Cephalodasys interinsularis n. sp.

Chordodes combiareolatus, a new species of horsehair worms (Nematomorpha) from Nagaland, India, with further comments on Chordodes moutoni.

The currently known diversity of horsehair worms (Nematomorpha) from India is only 17 species. We report here two female specimens found on two occasions on a terrace paddy field in Tsupo, Viswema, Kohima, Nagaland, India. Although found at the same location, both species differ in their cuticular structures.

Cryptic species of hairworm parasites revealed by molecular data and crowdsourcing of specimen collections.

Recognizing cryptic species promotes a better understanding of biodiversity, systematics, evolutionary biology, and biogeography. When cryptic species are disease-causing organisms, such as parasites, their correct recognition has important implications for the study of epidemiology, disease ecology, and host-parasite relationships. Freshwater nematomorphs (Nematomorpha: Gordiida) or hairworms, are an enigmatic yet fascinating group of parasites that are known to manipulate host behavior to aid transition from the parasitic phase, within terrestrial insects, to the free-living aquatic stage.

Comparative descriptions of non-adult stages of four genera of Gordiids (Phylum: Nematomorpha).

Freshwater hairworms infect terrestrial arthropods as larvae but are free-living in aquatic habitats as adults. Estimates suggest that only 18% of hairworm species have been described globally and biodiversity studies on this group have been hindered by unreliable ways of collecting adult free living worms over large geographical areas. However, recent work indicates that non-adult cyst stages of hairworms may be the most commonly encountered stages of gordiids in the environment, and can be used for discovering the hidden diversity of this group.

One new species and a new record of the genus Chordodes (Nematomorpha: Gordiida) from North-East India.

Fifteen species of freshwater Nematomorpha have been described from India, five of which belong to the genus Chordodes. This paper describes one new species of horsehair worms (Nematomorpha): Chordodes lasuboni and a new record, C. moutoni from North-East India, which raises the total number of described species from India to 17.

Novel techniques for biodiversity studies of gordiids and description of a new species of Chordodes (Gordiida, Nematomorpha) from Kenya, Africa.

We review recent advances in the use of non-adult gordiid cyst stages to locate gordiids over large geographical regions and new culturing techniques which can help overcome current difficulties in nematomorph biodiversity studies. Using these techniques, we collected a new species of gordiid as cysts in aquatic snails (Biomphalaria pfeifferi) from the Lake Victoria Basin, western Kenya, Africa and cultured them in the laboratory. We describe the adult free-living male and female worms using morphological (light and scanning electron microscopy) and molecular data as well as the life cycle, mating and oviposition behavior, egg strings, eggs, larvae, and cysts of this new species.

Survival of larval and cyst stages of gordiids (Nematomorpha) after exposure to freezing.

Hairworms infect terrestrial arthropods and are 1 of the most understudied groups of parasites. Recently, life cycles of 2 gordiids (Paragordius varius and Paragordius obamai) have been domesticated in the laboratory. We tested the viability of laboratory reared and post-frozen larval and cyst stages of the North American gordiid, P.

The magnitude of global marine species diversity.

Background: The question of how many marine species exist is important because it provides a metric for how much we do and do not know about life in the oceans. We have compiled the first register of the marine species of the world and used this baseline to estimate how many more species, partitioned among all major eukaryotic groups, may be discovered.

Results: There are ∼226,000 eukaryotic marine species described.

Going solo: discovery of the first parthenogenetic gordiid (Nematomorpha: Gordiida).

Despite the severe fitness costs associated with sexual reproduction, its persistence and pervasiveness among multicellular organisms testifies to its intrinsic, short-term advantages. However, the reproductive assurance hypothesis predicts selection favoring asexual reproduction in sparse populations and when mate finding is difficult. Difficulties in finding mates is especially common in parasites, whose life cycles involve multiple hosts, or being released from the host into the external environment where the parasite can find itself trapped without a sexual partner.