Testing the climatic variability hypothesis in edaphic and subterranean Collembola (Hexapoda).

The climatic variability hypothesis was applied to the thermal tolerance of edaphic and cave Collembola occupying contrasting environments. Collembola belonged to four categories - trogloxene, subtroglophile, eutroglophile and troglobiont - with a different degree of affinity to subterranean habitats. Altogether, specimens of 17 species were exposed to a one-hour laboratory survival test. The impact of temperature, species and species-temperature interaction on cold and heat survival was statistically significant. There was a decrease trend in cold and heat tolerance from trogloxenes, over subtroglophiles and eutroglophiles to troglobionts. It was shown that obligate cave species, restricted to climatic-stable cave conditions, retain a functional thermal resistance, i.e. the genetically determined ability to tolerate relatively broader temperature ranges. Our results outlined the direct relationship between the thermal tolerances of species and the size of their geographic distributions. It was also observed that cold resistance of Collembola decreased significantly with increasing species body length, indicating that body size plays an important role in temperature tolerances of arthropods inhabiting soil and subterranean habitats.

The food web in a subterranean ecosystem is driven by intraguild predation.

Trophic interactions of cave arthropods have been understudied. We used molecular methods (NGS) to decipher the food web in the subterranean ecosystem of the Ardovská Cave (Western Carpathians, Slovakia). We collected five arthropod predators of the species Parasitus loricatus (gamasid mites), Eukoenenia spelaea (palpigrades), Quedius mesomelinus (beetles), and Porrhomma profundum and Centromerus cavernarum (both spiders) and prey belonging to several orders. Various arthropod orders were exploited as prey, and trophic interactions differed among the predators. Linear models were used to compare absolute and relative prey body sizes among the predators. Quedius exploited relatively small prey, while Eukoenenia and Parasitus fed on relatively large prey. Exploitation of eggs or cadavers is discussed. In contrast to previous studies, Eukoenenia was found to be carnivorous. A high proportion of intraguild predation was found in all predators. Intraspecific consumption (most likely cannibalism) was detected only in mites and beetles. Using Pianka's index, the highest trophic niche overlaps were found between Porrhomma and Parasitus and between Centromerus and Eukoenenia, while the lowest niche overlap was found between Parasitus and Quedius. Contrary to what we expected, the high availability of Diptera and Isopoda as a potential prey in the studied system was not corroborated. Our work demonstrates that intraguild diet plays an important role in predators occupying subterranean ecosystems.

Subterranean Deuteraphorura Absolon, 1901, (Hexapoda, Collembola) of the Western Carpathians - Troglomorphy at the northern distributional limit in Europe.

An integrative approach employing molecular, morphological and geographical data were applied to species delimitation among Deuteraphorura congeners occupying caves of the Western Carpathian Mts. A new species of Deuteraphorura from the Western Carpathians is described. D. muranensis sp. nov. belongs among species with 4 pso at the hind margin of the head and possesses highly troglomorphic features. It is conspicuous with its distinctly elongated claws and long, hair-like body chaetae. The status of the new species was confirmed by DNA barcoding based on the mitochondrial COI marker. Populations of D. kratochvili (Nosek, 1963), the most widespread species, were studied in detail. Both ABGD and PTP analyses brought results congruent with geography, i.e. the molecular and geographic distance of the populations were positively correlated. However, some molecular separation based on pairwise distance and the number of substitutions was indicated within two of the studied populations. Despite the indistinct morphological differences, the tested populations were well isolated both geographically and genetically, which indicates that each studied population may represent a cryptic species. The troglomorphy of cave Collembola at the northernmost border of the distribution of cave-adapted species in the Europe is discussed. It is clear that the level of troglomorphy is closely associated with conditions of the microhabitat occupied by the individual subterranean species. The results of our study enhance the importance of the Western Carpathians regarding the diversity pattern of obligate cave species in Europe.

Contribution to the genus Plutomurus Yosii (Collembola, Tomoceridae): notes on the morphology of Plutomurus carpaticus Rusek amp; Weiner and P. unidentatus (Börner).

In two European species of the genus Plutomurus Yosii, P. carpaticus Rusek Weiner and P. unidentatus (Börner), several diagnostic morphological characters are specified and illustrated: body chaetotaxy, number of internal spine-like chaetae on tibiotarsi and number of teeth on claw. The contribution is based on the study of type specimens of both species and specimens of other populations of their distribution ranges. The numerous specimens of the genus Plutomurus collected recently in the Western Carpathian caves are the most similar to P. carpaticus, but differ in macrochaetotaxy and may represent a new species. Three types of macrochaetae on thorax and abdomen of Plutomurus congeners from the Europe and Caucasus are defined. Identification key to European Plutomurus species is provided.

Erratum: ANDREA PARIMUCHOVÁ & LUBOMÍR KOVÁC (2016) Redescription of two troglobiotic species of Deuteraphorura Absolon, 1901 (Collembola, Onychiuridae) from the Western Carpathians. Zootaxa, 4168: 327-340.

N/A.

A new troglobiotic Protaphorura (Collembola, Hexapoda) from the Siberia, Russia.

A new species of Protaphorura Absolon, 1901 (Collembola, Onychiuridae), P. cykini sp.nov., is described from a cold karst cave in the Irkutsk region, Siberia, Russia. It is an obligate cave species with the largest body size (4.3-5.6 mm) of all congeners. The species is further characteristic by the pseudocellar formula as 3(2)2/022/33343, high number of vesicles in postantennal organ (65-71) and subapical organite protected with two papillae. A partial sequence of cytochrome oxidase I (COI DNA barcoding marker) gene is used to verify the taxonomic status of the new species and the barcode sequence is compared with other congeners available in GenBank database. Distribution and diversity of cave Collembola of Siberia is discussed.

A new cave species of the genus Protaphorura Absolon, 1901 (Collembola, Onychiuridae) from the Western Carpathians (Slovakia) with critical comments to the Palaearctic representatives of the genus.

The new species Protaphorura borinensis sp. nov. from a cave of the Western Carpathians, Central Europe, is described. It belongs to congeners with ~40 vesicles in PAO and three pseudocelli at the base of antennae and the hind margin of head. P. borinensis sp. nov. has coarse granulation of cuticle on head, and specific distribution of "s" chaetae on abdominal terga and chaetotaxy of ventral tube. Critical comments to the Palaearctic representatives of the genus Protaphorura and an identification key to 85 species are provided.

Redescription of two troglobiotic species of Deuteraphorura Absolon, 1901 (Collembola, Onychiuridae) from the Western Carpathians.

Two species of the genus Deuteraphorura Absolon, 1901 from the Western Carpathian caves (Central Europe) are redescribed, namely D. kratochvili (Nosek, 1963) and D. schoenviszkyi (Loksa, 1967). Both species are characterized by the absence of pseudocelli on thoracic tergum I, presence of male ventral organ on abdominal terga II-III and 3 pseudocelli on hind margin of head. D. kratochvili is redescribed based on specimens from the type locality (Demänovská Cave System) and its intraspecific variability in morphological traits is discussed. Redescription of D. schoenviszkyi (Loksa, 1967) is based on specimens from the Slovak and Aggtelek Karst, the karst area where the type locality is situated. Both species are restricted to subterranean environment, thus classified as obligate cave forms (troglobionts). An identification key to Deuteraphorura species, characterized by absence of pseudocelli on thoracic segment I, is provided.