Dariusz Skarżyński

Biological invasions in soil: DNA barcoding as a monitoring tool in a multiple taxa survey targeting European earthworms and springtails in North America

Biological invasions are increasingly recognized as a potent force altering native ecosystems worldwide. Many of the best documented cases involve the massive invasions of North America by plant and animal taxa native to Europe. In this study, we use DNA barcoding to survey the occurrence and genetic structure of two major groups of soil invertebrates in both their native and introduced ranges: Collembola and earthworms. Populations of ten species of earthworms and five species of Collembola were barcoded from both continents. Most of these species exhibited a similar genetic structure of large and stable populations in North America and Europe, a result supporting a scenario of multiple invasions. This was expected for earthworm species involved in human economic activities, but not foreseen for Collembola species de facto unintentionally introduced. This study also establishes that invasive species surveys employing DNA barcoding gain additional resolution over those based on morphology as they allow evaluation of cryptic lineages exhibiting different invasion histories.

Challenging species delimitation in Collembola: cryptic diversity among common springtails unveiled by DNA barcoding

Abstract. Collembola is one of the major functional groups in soil as well as a model taxon in numerous disciplines. Therefore the accurate identification of specimens is critical, but could be jeopardised by cases of cryptic diversity. Several populations of six well characterised species of springtails were sequenced using the COI barcode fragment as a contribution to the global Collembola barcoding campaign. Each species showed high intraspecific divergence, comparable to interspecific sequence divergence values observed in previous studies and in 10 congeneric species barcoded here as a reference. The nuclear marker, 28S, confirmed all the intraspecific lineages found with COI, supporting the potential specific status of these entities. The implications of this finding for taxonomy and for disciplines relying on species names, such as evolution and ecology, are discussed.

Barcoding the Collembola of Churchill: a molecular taxonomic reassessment of species diversity in a sub-Arctic area

Although their functional importance in ecosystems is increasingly recognized, soil‐dwelling micro‐arthropods are usually poorly known in comparison with their above‐ground counterparts. Collembola constitute a significant and species‐rich component of the soil biodiversity, but it remains a woefully understudied group because of the taxonomic impediment. The ever‐increasing use of molecular taxonomic tools, such as DNA barcoding, provides a possible solution. Here, we test the use of this approach through a diversity survey of Collembola from the vicinity of Churchill, Manitoba, Canada, and compare the results with previous surveys in the same area and in other sub‐Arctic regions. The systematic barcoding campaign at Churchill revealed a diverse collembolan fauna consisting of 97 species‐level MOTUs in six types of habitats. If all these MOTUs are confirmed as species, this richness would be far higher than prior records for Arctic Canada and could lead to reconsider the actual diversity of the group in Arctic environments.

Biology and key to the Australian species of Hypogastrura and Ceratophysella (Collembola: Hypogastruridae)

The family Hypogastruridae is represented by nine genera in Australia, three of which: Mesogastrura Bonet, Hypogastrura Bourlet and Ceratophysella Börner, consist only of species that have been probably introduced from Europe within the last 250 years, with the exception of a new species described here. All species in these three genera are typical of, and abundant in, disturbed habitats. The 11 species currently recorded from Australia in Hypogastrura and Ceratophysella are C. communis (Folsom, 1897), C. denticulata (Bagnall, 1941), C. gibbosa (Bagnall, 1940), C. succinea (Gisin, 1949), Hypogastrura assimilis (Krausbauer, 1898), H. distincta (Axelson, 1902), H. manubrialis (Tullberg, 1869), H. purpurescens (Lubbock, 1867, H. vernalis (Carl, 1901) and H. viatica (Tullberg, 1872), and a new species C. pauciseta sp. nov. Ceratophysella communis was misidentified in some published literature as C. engadinensis Gisin, 1949. Although C. communis is confirmed as occurring in Australia, there now seems to be no evidence that C. engadinensis occurs here, and the name H. denticulata may include more than one species. An illustrated dichotomous key and description is given here for all Australian species of Hypogastrura and Ceratophysella, and their distributions and habitats documented. Their value as indicators of disturbed habitats in Australia is discussed. Collembola in general have been shown to have a positive influence on nutrient cycling. It is not known what contribution Hypogastrura and Ceratophysella make to Australian arable and grazing systems in this respect, but it may be considerable because of their abundance.

Endonura Cassagnau in Iran, with a key to species of the genus (Collembola, Neanuridae, Neanurinae)

Abstract Three new species of Endonura are described from Iran. Endonura dichaeta sp. n. can be recognized by an ogival labrum, head without chaetae O and E, chaeta D connected with tubercle Cl, tubercle Dl with five chaetae on head, absence of tubercles Di on thorax I and tubercle (Di+Di) of thorax V with 2+2 chaetae. Endonura ceratolabralis sp. n. is characterized by large body size, reduction of labral chaetotaxy, ogival labrum, head without chaeta O and fusion of tubercles Di and De on first thoracic segment. Endonura persica sp. n. is distinguished from its congeners by a nonogival labrum, absence of chaeta O, tubercles Dl and (L+So) with five and eight chaetae respectively and claw with inner tooth. The key to all species of the genus is given.

Description of Hypogastrura ellisi sp. n. with notes on H. tethyca Ellis and the trybomi group (Collembola, Hypogastruridae)

Abstract A new species, Hypogastrura ellisi, from Iran and Greece is described. It does not fit the definition of any known species group, but, as it has weakly differentiated blunt Ant. IV sensilla, one tenent hair on tibiotarsi, broad empodial lamellae, and dens with fine granulation and seven setae, it can be compared with some members of the trybomi and monticola groups and H. aterrima Yosii, 1972. It seems to be especially close to a representative of the trybomi group, H. tethyca Ellis, 1976. They differ mainly in the shape of apical papillae on the labrum, the size of anal spines, and the presence of setae m2 on Th. II. Notes on H. tethyca, the trybomi group, and a key to the species of the group are given.

Figures 1 – 6. H In A New Species And New Records Of The Genus Hypogastrura Bourlet, 1839 (Collembola, Hypogastruridae) From Iran

FIGURES 1 – 6. H. persica sp. nov.: 1, chaetotaxy of thoracic tergum II; 2, chaetotaxy of abdominal terga III – VI; 3, postantennal organ and ocelli; 4, claw III with empodial appendage; 5, furca; 6, chaetotaxy of antennal segments III – IV.

A Case of Unusual Sexual Dimorphism in a New Springtail Genus and Species from the United States (Collembola: Onychiuridae: Onychiurinae)

ABSTBACT Kennethia pomorskii, a new genus and species of subfamily Onychiurinae is described from North America. It has a unique suite of apomorphic morphological characters and is most closely related to Arneria Pomorski, 2000; Dinochiurus Pomorski & Steinmann, 2004; and Reducturus Pomorski & Steinmann 2004. A key to genera of the tribe Hymenaphorurini is given.

A new species and a new record of the genus Hypogastrura Bourlet, 1839 (Collembola, Hypogastruridae) from Poland

Hypogastrura szeptyckii sp. n. is described from Poland (KrakowskoWieluñska Uppland and Pieniny Mountains). Hypogastrura franconiana (STACH, 1949) is recorded from Poland (Sudetes) for the first time.