Małgorzata Kolicka

Bifidochaetus, a new Arctic genus of freshwater Chaetonotida (Gastrotricha) from Spitsbergen revealed by an integrative taxonomic approach

Abstract. Gastrotricha is a cosmopolitan phylum of aquatic and semi-terrestrial invertebrates that comprises ∼820 described species. To date, freshwater gastrotrichs have not been the subject of faunistic or taxonomic research in the polar regions. In this paper, we present the first species-level description of a freshwater gastrotrich from the Arctic (Svalbard Archipelago). Evidence from morphology, morphometry and molecular analyses reveals that the species represents a new genus in Chaetonotidae: Bifidochaetus arcticus, gen. et sp. nov. Taking into consideration many morphological similarities to Chaetonotus (Primochaetus) veronicae Kånneby, 2013 we propose to include C. (P.) veronicae in the newly established genus under the new combination Bifidochaetus veronicae (Kånneby, 2013), comb. nov. In the phylogenetic analysis based on nuclear 18S rRNA, 28S rRNA and mitochondrial cytochrome c oxidase subunit I sequence data, B. arcticus, gen. et sp. nov. is nested within the family Chaetonotidae, as the sister group to the genus Lepidochaetus Kisielewski, 1991. In this paper we also present new taxonomic characters useful for gastrotrich taxonomy: the pharynx-to-intestine length ratio (I) and the spine bifurcation ratio (B).

Prey or parasite? The first observations of live Euglenida in the intestine of Gastrotricha

Euglenida are an important element in almost all aquatic ecosystems. They are known to parasitize animals such as copepods and flatworms, but have never been found in any other microscopic group. Gastrotrichs, a phylum of small microinvertebrates, are a constant and important element of marine and freshwater ecosystems. During our observation, 72 live gastrotrich specimens were collected from Europe (Poland, Germany) and South America (Brazil) containing active Euglenida of the genus Heteronema. Euglenida were found in the intestine of 10.4%, 52.6% and 1% of gastrotrichs, respectively. Taking into consideration the existing parasitism in euglenoids, it may be hypothesized that they either constitute fortuitous feed in the gastrotrich intestine or they are parasites or commensals. These observations suggest a new, so far unknown type of interaction between Gastrotricha and protists.

Gastrotrichs in bromeliads — newly recorded Chaetonotus (Hystricochaetonotus) furcatus Kisielewski, 1991 (Chaetonotida) from the Łódź Palm House

ABSTRACT Chaetonotus (Hystricochaetonotus) furcatus Kisielewski, 1991 was found during a study of fauna in water micro-reservoirs with bromeliads exhibited at the Łódź Palm House (Poland). This freshwater gastrotrich species was previously known only from the locus typicus in central Amazonia (Brazil). This observation constitutes the first finding of gastrotrichs in water microreservoirs formed in the axils of Bromeliaceae in artificial habitats such as greenhouses. It also raises the number of freshwater gastrotrichs found in palm houses to 19, and the number of nominal species known from Poland to 100. Newly recorded species correspond to the original descriptions but differ in some characters. Taxonomic, morphometric and biogeographic remarks are provided for the species together with microphotographs and drawing figures.

Palm house – biodiversity hotspot or risk of invasion? Aquatic invertebrates: The special case of Monogononta (Rotifera) under greenhouse conditions

Abstract Greenhouses form favourable conditions for establishing stable populations of native as well as invasive alien microinvertebrates. Investigations of palm houses have a long tradition and native, alien and new species for science have been found in many of them. The examined pond and some microreservoirs in Bromeliaceae and Agavoideae in Pozna´n Palm House (Poland) sampled in 2012, appeared to contain representatives of Rotifera (64 species), Copepoda (2 species), Polychaeta, Acari and Insecta larvae. The most abundant Rotifera species were: Anuraeopsis fissa Gosse, 1851, Ascomorpha ecaudis Perty 1850, Euchlanis dilatata Ehrenberg, 1832, Pompholyx sulcata Hudson, 1885 and Trichocerca rousseleti Voight, 1902. Moreover, rotifers considered to be rare in Poland, i.e., Asplanchna herricki De Guerne, 1888, Collotheca pelagica Rousselet, 1893, Colurella sulcata Stenroos, 1898, Gastropus minor Rousselet, 1892 were also detected in Pozna´n Palm House. Two recorded Copepoda species were Phyllognathopus viguieri (Maupas, 1892) found in agave microreservoirs and Mesocyclops leuckarti (Claus, 1857) found in reservoir with aquatic plants. For biodiversity evaluation of rotifers Margalef’s and Shannon-Wiener’s indexes were used and in order to determine species richness the Simpson index was calculated. Additionally, a complete list of all aquatic invertebrates is presented, i.e., Plathelmintes (11 species), Nemeretea (2 species), Oligochatea (13 taxa), Polychaeta (7 species), Gastrotricha (13 taxa) and Copepoda (1 species) previously recorded in Pozna´n Palm House. To sum up, Palm houses create a convenient habitat for a prevalence of native and introduced invertebrates and are a putative source of alien species, possibly facilitating their release to the environment.

Gastrotricha Mečnikow, 1865 from Copenhagen Palm House — contribution to the knowledge of Lepidodermella intermedia Kånneby, Todaro & Jondelius, 2012 (Chaetonotida, Gastrotricha)

ABSTRACT Gastrotricha Mečnikow, 1865 compose a cosmopolitan phylum of aquatic and semi-aquatic invertebrates comprising over 850 described species, that are known to inhabit various aquatic ecosystems from all over the world where they often show high density and diversity. Up to now Gastrotricha have been studied in artificial habitats, such as greenhouses only in the Poznań Palm House (Poland). In May 2013 a preliminary study was conducted in the Copenhagen Palm House (Denmark) to provide additional evidence of the presence of gastrotrichs in anthropogenic water bodies in greenhouses. Five species were found: Ichthydium podura Müller, 1773, Lepidodermella intermedia Kånneby, Todaro & Jondelius, 2012, Chaetonotus (Hystricochaetonotus) macrochaetus Zelinka, 1889, Chaetonotus (Hystricochaetonotus) sp., and Chaetonotus (Chaetonotus) sp. Lepidodermella intermedia is new to Danish fauna and constitutes the second record of this species. Detailed taxonomic and morphological remarks are provided for this newly recorded species.

New Arctic Gastrotricha — Three Chaetonotus (Chaetonotidae) from Longyearbyen (Spitsbergen, Svalbard Archipelago)

Abstract. Gastrotricha is a cosmopolitan phylum of aquatic and semi-terrestrial invertebrates comprising over 820 described species. Virtually no taxonomic or faunistic data exist on freshwater Gastrotricha of the Arctic. So far, 10 studies have recorded Gastrotricha from the entire area of the Svalbard Archipelago; only in two were gastrotrichs determined to the genus and species levels. The remaining studies only reported the presence of Gastrotricha as a phylum. In this article, I present the results of research on freshwater Gastrotricha from the area of fjord Isfjorden (Spitsbergen, Arctic). The collected material contained representatives of 8 species, 2 subgenera of Chaetonotus namely Chaetonotus (Chaetonotus) Erhenberg, 1830 and Chaetonotus (Hystricochaetonotus) Schwank, 1990, two genera namely Chaetonotus Erhenberg, 1830 and Bifidochaetus Kolicka et Kisielewski, 2016, both belonging to the family Chaetonotidae Gosse, 1864 (sensu Leasi and Todaro, 2008). I describe 3 new species from the Chaetonotidae: Chaetonotus (Chaetonotus) jaceki sp. nov., C. (C.) gelidus sp. nov., and C. (C.) svalbardi sp. nov., together with data on the range, frequency and abundance of all noted species. Furthermore, a record abundance of Gastrotricha was noted, amounting to more than one thousand specimens per 1 cm3 of bottom sediment.

Applicability of cryoconite consortia of microorganisms and glacier-dwelling animals in astrobiological studies

Abstract For several years it has been of interest to astrobiologists to focus on Earth’s glaciers as a habitat that can be similar to glaciers on other moons and planets. Microorganisms on glaciers form consortia – cryoconite granules (cryoconites). They are granular/spherical mineral particles connected with archaea, cyanobacteria, heterotrophic bacteria, algae, fungi, and micro animals (mainly Tardigrada and Rotifera). Cryophilic organisms inhabiting glaciers have been studied in different aspects: from taxonomy, ecology and biogeography, to searching of biotechnological potentials and physiological strategies to survive in extreme glacial habitats. However, they have never been used in astrobiological experiments. The main aim of this paper is brief review of literature and supporting assumptions that cryoconite granules and microinvertebrates on glaciers, are promising models in astrobiology for looking for analogies and survival strategies in terms of icy planets and moons. So far, astrobiological research have been conducted on single strains of prokaryotes or microinvertebrates but never on a consortium of them. Due to the hypothetical similarity of glaciers on the Earth to those on other planets these cryoconites consortia of microorganisms and glacier microinvertebrates may be applied in astrobiological experiments instead of the limno-terrestrial ones used currently. Those consortia and animals have qualities to use them in such studies and they may be the key to understanding how organisms are able to survive, reproduce and remain active at low temperatures.

Hidden invertebrate diversity – phytotelmata in Bromeliaceae from palm houses and florist wholesalers (Poland)

Abstract Bromeliads accumulate water in the leaf axils (forming phytotelmata), which may then form a habitat for many animal species of both invertebrates and vertebrates. In temperate regions, bromeliads are commonly displayed in palm houses and distributed by florist wholesalers. Taking into account the fact that global plant trade can be a source of spreading alien species, the phytotelmata that had formed within the bromeliads were examined here in order to study the protists and invertebrates associated with this habitat. In the examined Bromeliaceae micro-reservoirs representatives of testate amoebae (Euglyphida and Arcellinida), Gastrotricha, Nematoda, Rotifera, Polychaeta, Cladocera, Copepoda and mites (Oribatida, Mesostigmata and Heterostigmatina) were found. Additionally, unidentified Nemertea, Turbellaria, Insecta larvae and single representative of Mollusca were also found. Thirty taxa are recorded for the first time from bromeliads micro-reservoirs. Among the identified taxa, the gastrotrich Chaetonotus (Hystricochaetonotus) furcatus Kisielewski, 1991 was found, which was previously known only from bromeliads in the natural environment in South America. Nematodes belonging to Clarkus spp. were found in the Bromeliaceae reservoirs for the first time. Additionally, the tropical mite Phthiracarus (Phthiracarus) phoxos Niedbała, 2004, previously known from Cuba in the natural environment and other greenhouses in Poland, was also found in the studied phytotelmata. Steneotarsonemus ananas (Tryon, 1898) sensu Beer, 1954 was recorded from Poland for the first time. Some of the mite specimens, e.g., Mesostigmata and Heterostigmatina, had most likely accidentally been caught in the phytotelmatum, which acted like a trap; but others, especially freshwater fauna representatives can be a constant element of the phytotelmata merocenoses. Our study provides comprehensive analysis of fauna living in these exceptional micro-habitats, and it underlines the possibility of passive invertebrate dispersal within bromeliad micro-reservoirs and between different localities, e.g., florist shops and markets as well as greenhouses.