New Tardigrade Species Research Articles

New Species of Macrobiotidae (Eutardigrada) from Cameroon (Africa), Characteristics of Macrobiotus Morpho-Groups and a Key to the Nelsonae Group

In a moss sample from Cameroon a few specimens and eggs of a new species of tardigrade were found. Macrobiotus stanislausi sp. nov. belongs to the Macrobiotus nelsonae morpho-group and is most similar to Mac. ragonesei. However, it differs from Mac. ragonesei mainly by the shape of the egg processes and the absence of annulations on process endings. A dichotomous key for Macrobiotus nelsonae morpho-group is also proposed. Moreover, the genus Macrobiotus is divided into 12 morpho-groups based on morphology of the eggs to facilitate future taxonomic research on this genus.

Integrative description of Hypsibius repentinus sp. nov. (Eutardigrada: Hypsibiidae) from Sweden

A new species of tardigrade from the genus Hypsibius Ehrenberg, 1848 is described from the bottom sediments of a small lake in the central part of Scandinavian Peninsula (Sweden), using an integrative approach, i.e. morphological techniques (light and scanning electron microscopy) combined with a molecular analysis (18S rRNA, 28S rRNA, ITS-2 and COI markers). Hypsibius repentinus sp. nov. belongs to the Hypsibius dujardini species–group and differs from the most similar species of this group in having a second macroplacoid with a definite constriction and in some other morphometric characters. Morphological diagnosis for the Hypsibius dujardini species–group is proposed, and its composition is discussed.

Claxtonia goni, a new species of Tardigrada (Heterotardigrada, Echiniscidae) from the island of Maui (Hawaiian Islands, U.S.A., North Pacific Ocean), with notes to the genus Claxtonia Gąsiorek amp; Michalczyk, 2019.

A new Tardigrada species, Claxtonia goni sp. nov. is described from specimens collected in the central area of the Haleakalā National Park, the island of Maui, Hawaii, U.S.A. The new species and Clx. pardalis (Degma Schill, 2015) together with several examples of Clx. wendti (Richters, 1903) are the only known Claxtonia species with the plates having an intracuticular pattern resembling that on a leopard's fur. Claxtonia goni sp. nov. differs from Clx. pardalis in the absence of pores on leg plates, in smaller and uniform pores on dorso-lateral plates, in very unequally spaced teeth in the dentate collar, in lesser ratio of internal cephalic cirrus and lateral cirrus A lengths, and in relatively shorter claws in fourth pair of legs. The differences between the new species and the other congeners as well as Echiniscus species with the same cirri composition and similar cuticular sculpture are also defined. The diagnosis of the genus Claxtonia is amended and three Echiniscus species are transferred into the genus with the proposed new combinations: Claxtonia aliquantilla (Grigarick, Schuster Nelson, 1983) comb. nov., Clx. mosaica (Grigarick, Schuster Nelson, 1983) comb. nov. and Clx. nigripustula (Horning, Schuster Grigarick, 1978) comb. nov..

Two new species of Tardigrada from moss cushions (Grimmia sp.) in a xerothermic habitat in northeast Tennessee (USA, North America), with the first identification of males in the genus Viridiscus.

BackgroundThe phylum Tardigrada consists of over 1,300 species that inhabit terrestrial, freshwater and marine environments throughout the world. In terrestrial habitats they live primarily in mosses, lichens, leaf litter and soil, whereas tardigrades in freshwater and marine environments are mainly found in sediments and on aquatic plants. More than 65 species have been previously reported in the state of Tennessee, USA.MethodsTardigrades present in moss cushions (Grimmia sp.) collected from a xerothermic habitat on the East Tennessee State University campus, Johnson City, TN, USA, were extracted, mounted on slides, identified, and counted. Additional samples of fresh dried moss were used for integrative analyses, including morphological analysis with phase contrast (PCM) and scanning electron microscopy (SEM), as well as molecular analyses of COI, 18S rRNA, 28S rRNA, and ITS-2 of the Macrobiotus and Milnesium species.ResultsFive species were found, including two species new to science: Viridiscus miraviridis sp. nov. and Macrobiotus basiatus sp. nov. Viridiscus miraviridis sp. nov. differs from other members of the genus mainly by having a different type of dorsal cuticle and some other, more subtle, morphometric characters. In addition to the two new species, Viridiscus perviridis and Viridiscus viridissimus were present, and males of Vir. viridissimus were found for the first time, the first record of males in the genus Viridiscus. Macrobiotus basiatus sp. nov. is most similar to Macrobiotus nelsonae, but it differs from Mac. nelsonae mainly by the stylet supports being situated in a more anterior position, shorter and narrower egg processes, and a smaller number of areoles around the egg processes. Moreover, the identification of Milnesium inceptum was confirmed as the first record for the USA by analysis of COI.

A new species of Diphascon (Tardigrada: Hypsibiidae) from Northern China supported by integrated taxonomy.

Morphological and molecular analyses have determined that there is a new species of Tardigrada found in China. Diphascon wuyingensis sp. nov., has smooth cuticle, pharyngeal apophyses, three rod-shaped macroplacoids (increasing in length from first to third, with the second macroplacoid clearly longer than the first) and lacks microplacoids and septulum. The new species has a very small drop-shaped formation and small claws of the Hypsibius type, but no pseudolunules or other cuticular thickenings. Three individual specimens and a group of four specimens were used for DNA isolation and 18S rRNA and COI sequencing; the p-distances to another three Diphascon species used for comparison varied in ranges of 8.8-10.2% (18S rRNA) and 24.2-26.7% (COI).

Two new species of Tardigrada from Ecuador (South America).

In two moss samples collected in El Cajas National Park (Azuay Province, Ecuador), 33 specimens and 19 eggs of a new species of Macrobiotus and 56 heterotardigrades belonging to a new Echiniscus species were extracted. Macrobiotus dulciporus sp. nov. belongs to the hufelandi group and is most similar to Macrobiotus maculatus Iharos, 1973. It differs from M. maculatus mainly based on the presence of an oral cavity armature of the patagonicus type, smooth egg chorion surface, lower number of processes on the egg circumference and some morphometric characters of the egg processes. Echiniscus hannae sp. nov. belongs to the bigranulatus group, but differs from all species in this group due to the presence of large, smooth areas on its dorsal plate.

Tardigrades of the Canopy:Milnesium burgessinov. sp. (Eutardigrada: Apochela: Milnesiidae) a New Species from Kansas, U.S.A.

Milnesium burgessi nov. sp. is a new species of tardigrade described from the canopy of eastern Kansas, USA. This unique tardigrade of class Eutardigrada, order Apochela and family Milnesiidae is characterized by its smooth cuticle, six peribuccal lamellae, long primary branch of the claws with accessory points, a claw configuration of [3-3]-[3-3] and a buccal tube that is significantly shorter than other species.

Echiniscoides rugostellatusa new marine tardigrade from Washington, U.S.A. (Heterotardigrada: Echiniscoidea: Echiniscoididae: Echiniscoidinae)

Abstract The first new species of tardigrade in the family Echiniscoididae from the west coast of America is presented with an integrative description. Echiniscoides rugostellatus n. sp. was found on barnacles from a piling, in the Straits of Juan Fuca, Puget Sound, Port Townsend, Washington, USA. The new species is named after its granulated dorsal cuticle and the star-shaped tip of its internal and external cirri. The new species is separated from all other Echiniscoides by its granulated cuticle with flat patches, the number of claws on the legs of the adult and the structure of the buccal cirri.

Echiniscoides wyethi, a new marine tardigrade from Maine, U.S.A. (Heterotardigrada: Echiniscoidea: Echiniscoididae)

Abstract A new species of tardigrade in the family Echiniscoididae, Echiniscoides wyethi, was found on the barnacle Semibalanus balanoides (L.) at several intertidal sites around Allen Island, Maine, USA. The new species is named after the American artist Andrew Wyeth and the Wyeth family who own the island on which this species was discovered. The new species is separated from all other Echiniscoides by the smooth cuticle, long flexible buccal tube, and the number of claws on the legs of the adult.

Echiniscus pardalisn. sp., a new species of Tardigrada (Heterotardigrada, Echiniscidae,arctomysgroup) from the Parco Naturale delle Alpi Marittime (NW Italy)

A new species of Tardigrada Doyère, 1840, Echiniscus pardalis n. sp., is described from two moss samples collected in the Parco Naturale delle Alpi Marittime (NW Italy). It belongs to the Echiniscus arctomys species-group, but differs from other 49 known members of the group mainly by the irregularly and distantly scattered deep pores on the plates and by a unique subsurface cuticular pattern on the plates, resembling that of a leopard's fur. The new species is most similar to eight species from the arctomys group: E. barbarae Kaczmarek & Michalczyk, 2002, E. crebraclava Sun, Li & Feng, 2014, E. dearmatus Bartoš, 1935, E. mosaicus Grigarick, Schuster & Nelson, 1983, E. nigripustulus Horning, Schuster & Grigarick, 1978, E. nobilis Mihelčič, 1967, E. tardus Mihelčič, 1951 and E. vinculus Horning, Schuster & Grigarick, 1978. The differences between the new species and these eight species are thoroughly discussed. They mainly concern the presence/absence and relative size of shallow dimples surrounding individual tubercles, the relative length of cirrus A, the presence/absence of a spine on the first pair of legs, the presence/absence of a spur on the internal/external claws and the number of teeth on the collar of the hind legs. This paper is the first result published on Tardigrada collected during the European Distributed Institute of Taxonomy's in All Taxa Biodiversity Inventories Monitoring programme.

A new species of the genusDoryphoribius(Eutardigrada: Isohypsibiidae) from China

Abstract A new species of tardigrade (Eutardigrada: Isohypsibiidae) was discovered in moss in the Wuyi Mountains, Fujian Province, southeastern China. Doryphoribius mcinnesae, new species, belongs to the evelinae group because it has two macroplacoids and displays cuticular gibbosities. The surface of the body on the dorsal and lateral sides is sculptured with a reticular formation. The first macroplacoid is longer than the second one; lunules and cuticular bars on legs are absent. It differs from the other members of the group by having a different gibbosity configuration (X: 2-3-1-3-1-3-1-2-2-2) or cuticular sculpture. The paper includes a detailed comparison of the new species with other similar but different species.

Two new tardigrade species from Sicily.

Two new species of tardigrades are described from Sicilian moss samples: Macrobiotus insuetus sp. nov. and Diphascon (Diphascon) procerum sp. nov. Macrobiotus insuetus sp. nov. is a species of the harmsworthi-group characterized by both posterior and anterior claws of the hind legs, which are different in shape from those of the first three leg pairs. The IV claws have extended basal tract where the branches are joined and the secondary branch breaks at near right angle to the primary branch and is clearly shorter than the main branch and the secondary branch of claws I-III. The eggs are not areolated and have conical processes with a reticular ornamentation. Diphascon (D.) procerum sp. nov. has a delicate cuticular ornamentation of very small tubercles, almost dots; two macroplacoids and septulum are present; thin accessory points are present on the main branches of the slender claws; lunules are absent but the base of the external claws of the hind legs are enlarged and slightly indented; a cuticular bar is present near the internal claw of the first three leg pairs and two cuticular bars are present on the hind legs between the base of the claws and near the base of the anterior claw.

<strong>Two new tardigrade species from Sicily</strong>

Two new species of tardigrades are described from Sicilian moss samples: Macrobiotus insuetus sp. nov. and Diphascon (Diphascon) procerum sp. nov. Macrobiotus insuetus sp. nov. is a species of the harmsworthi-group characterized by both posterior and anterior claws of the hind legs, which are different in shape from those of the first three leg pairs. The IV claws have extended basal tract where the branches are joined and the secondary branch breaks at near right angle to the primary branch and is clearly shorter than the main branch and the secondary branch of claws I-III. The eggs are not areolated and have conical processes with a reticular ornamentation. Diphascon (D.) procerum sp. nov. has a delicate cuticular ornamentation of very small tubercles, almost dots; two macroplacoids and septulum are present; thin accessory points are present on the main branches of the slender claws; lunules are absent but the base of the external claws of the hind legs are enlarged and slightly indented; a cuticular bar is present near the internal claw of the first three leg pairs and two cuticular bars are present on the hind legs between the base of the claws and near the base of the anterior claw.

Two new species of Tardigrada (Echiniscidae, Hypsibiidae) from China

Abstract Two new species of Tardigrada are described. Echiniscus crebraclava, new species, is similar to Echiniscus marginoporus Grigarick, Schuster & Nelson, 1983. It differs from E. marginoporus by thick clava and by different cuticular sculpture. Diphascon (Adropion) gani, new species, is characterized by having two macroplacoids, of which the second macroplacoid is elliptical and much short than the first one. It differs from D. (A.) belgicae Richters, 1911 by the elliptical second macroplacoid which is much shorter than the first one, by the first macroplacoid with constriction, by lacking microplacoid, by having septulum, and by lacking any cuticular bar near the base of claws on all legs. The new species differs from D. mariae (Mihelcic, 1951) by have eyespots, by the elliptical second macroplacoid, by lacking microplacoid and by having septulum. The new species differs from D. punctatum (Iharos, 1962) by having eyespots, by smooth cuticle, by the elliptical second macroplacoid, which is much short...

Milnesium lagniappe,a New Species of Water Bear (Tardigrada, Eutardigrada, Apochela, Milnesiidae) from the Southern United States

ABSTRACT. Over 200 species of freshwater and terrestrial water bears (phylum Tardigrada) are known to occur in North America. Of these, 20 species have been recorded in Louisiana. Foliose and fruticose lichen and moss samples collected in 2011 in the city of Lake Charles and in Sam Houston Jones State Park, Calcasieu Parish, Louisiana, USA, were stored in paper envelopes and later soaked in tap water overnight. Tardigrade specimens and eggs were extracted and mounted in polyvinyl lactophenol. The samples contained a new species of tardigrade. Milnesium lagniappe sp. n. has claw formula [2–3]-[3–2] and 9 sculptured bands in the dorsal and lateral cuticle. The new species most closely resembles Milnesium reticulatum, a species known only from the Seychelles Islands, in its cuticular pattern. However, M. lagniappe sp. n. is almost twice as large as M. reticulatum, lacks gibbosities, has proportionally wider buccal tube and longer claws, and has a more posterior point of stylet insertion. Reexamination of tar...

A new water bear, Minibiotus julianae, from the Caribbean Island of Dominica (Tardigrada: Eutardigrada: Parachela: Macrobiotidae)

A new species of tardigrade, Minibiotus acadianus, is described from a moss sample collected in June 2009 from a rainforest palm tree on the island of Dominica, West Indies. The new species has a buccal tube with a single anterior curvature, two macroplacoids, and a microplacoid. The cuticle is smooth with small, evenly-distributed circular or elliptical pores. Eggs have a reticulated shell surface and short inverted goblet egg process; a dentate margin on the distal dish of the processes bears 10–12 short teeth. The new species is most similar to Minibiotus acadianus Meyer & Domingue, 2011; both have wider buccal tubes than other species in the genus. The new species is easily distinguished from M. acadianus in lacking cuticular gibbosities and in some characters of the egg.

Macrobiotus trunovae sp.n., a new species of tardigrade from Russia

Macrobiotus trunovae sp.n., a new species of tardigrade from Russia

Tardigrades of North America: Oreella chugachii, a new species (Heterotardigrada, Echiniscoide, Oreellidae) from Alaska

A new species of tardigrade in the genus Oreella (Heterotardigrada, Echiniscoide, Oreellidae) is described from Girdwood, Alaska, U.S.A., North America. Oreella chugachii, new species, has single granulation, a short cirri A, and a small primary clava. The pharyngeal tube is long and flexible, eyes may be present, and the eggs have small pointed tips on their projections. In addition, a segment of the 18s rDNA gene is filed with GenBank as part of the description. The discovery in the northern hemisphere of a population of a new species of Oreella, a previously monotypic, Gondwanian genus, expands the biogeography of what is believed to be a foundation group for limno-terrestrial tardigrades.

Milnesium zsalakoae and M. jacobi, two new species of Tardigrada (Eutardigrada: Apochela: Milnesiidae) from the southwestern United States

Two new species of the phylum Tardigrada belonging to the genus Milnesium are described. Two specimens of Milnesium zsalakoae, new species, were collected from foliose lichens on rocks in Arizona and New Mexico, U.S.A. and mounted in Hoyer's medium. Milnesium zsalakoae has primary claw branches of great length and slenderness, substantially longer relative to the length of the buccal tube than those of any other species of Milnesium. Eleven specimens of Milnesium jacobi, new species, were found in foliose and fruticose lichens collected in eastern Texas, U.S.A. and mounted in Hoyer's medium or polyvinyl lactophenol. Milnesium jacobi differs from all species of Milnesium in having a very broad, cylindrical buccal tube and in the posterior placement of its stylet support insertions.

Description of three new species of Tardigrada from the Seychelles

Description of three new species of Tardigrada from the Seychelles