Croatian Biospeleological Society

Zagreb, Croatia

Croatian Biospeleological Society

Zagreb, Croatia
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Jovanovic Glavas O.,Josip Juraj Strossmayer University of Osijek | Jalzic B.,Croatian Biospeleological Society | Bilandzija H.,Ruder Boskovic Institute
International Journal of Speleology | Year: 2017

Caves are some of the least-known ecosystems on Earth and long-term ecological studies and population size estimates are very rare. Genus Congeria is a Tertiary relict that comprises three species from Dinaric karst area; C. kusceri, C. jalzici and C. mulaomerovici, each with very limited distribution. They are the only known cave bivalves and in contrast to many other cave species, they form populations with high densities. We estimated that the population of C. kusceri in Jama u Predolcu is between 72,454 and 72,906 individuals. The highest density occurred between one and three meters depth, and reached maximum of 1,625 individuals per square meter. Here we also present the results of a two-year water temperature and water level survey in several C. kusceri and C. jalzici localities. Data loggers showed that C. jalzici occurs in colder caves and higher water level oscillations then C. kusceri. From our data, it is obvious that the natural hydrological conditions in Congeria habitats were seriously altered. This and a series of other threats led to Congeria species being highly endangered. During low water levels, a part of the bivalve population becomes exposed to air in most localities. Uniquely, they are active during that period and are able to survive those conditions for more than 2 months. © 2017, Societa Speleologica Italiana. All rights reserved.

Krsinic F.,Croatian Institute Of Oceanography And Fisheries | Cukrov N.,Ruder Boskovic Institute | Kutlesa P.,Croatian Biospeleological Society | Jalzic B.,Croatian Biospeleological Society
Natura Croatica | Year: 2012

In the framework of our research, this study was focused on crustaceans in the anchihaline caves along the Eastern Adriatic coast. From August 2002 to June 2006 we collected 99 samples in 39 anchihaline caves. A total of 33 crustacean taxa were identified. Affinities were found in the rare, endemic or ecologically restricted crustaceans recorded in fewer than 10 caves, belonging to copepods, isopods and amphipods. A high species richness was recorded in the Central Adriatic threshold and the South Adriatic Basin. Stratified caves rich in organic matter or even heavy metals had the highest species richness. The cave Medvjed{stroke}a špilja on Lošinj Island was detected as a hot spot with 12 recorded taxa.

Lojen S.,Jozef Stefan Institute | Cukrov M.,Croatian Biospeleological Society | Cukrov N.,Ruder Boskovic Institute
Estuaries and Coasts | Year: 2014

This paper examines how the mixing of freshwater and seawater, and related mixing of freshwater and marine particulate organic matter (POM) in the permanently stratified estuary of the River Krka, Croatia, are reflected in the stable isotope fingerprints of soft tissues and tubes of the serpulid Ficopomatus enigmaticus. The carbon stable isotope composition (δ13C values) of the river-borne POM is retained over long distances, causing a depletion in 13C of POM in brackish waters. A trophic depletion in 13C was recorded in serpulid soft tissues. The serpulid carbonate tubes were depleted in 13C even at locations with salinity close to that of the sea and were subject to large isotope fractionation between dissolved inorganic C (DIC) and carbonate caused by vital effects, making carbonate depleted in 13C by several per mil compared with DIC. These effects, though large in the freshwater zone, fade towards the sea. The carbonate δ18O values of tubes reflect the δ18O values of the water. The temperature-related differences in δ18O values of tubes from different sites are masked by source-related differences in the δ18O values of water arising from mixing of freshwater and seawater in the estuary. Therefore, in serpulide tubes, the terrestrial component can easily be overestimated because of vital effects during biomineralisation and trophic depletion in 13C in freshwater and brackish environments. © 2013 Coastal and Estuarine Research Federation.

This paper presents a checklist with historical overview and new records on the cave-dwelling terrestrial isopods (troglophiles and troglobionts) from Croatia, based on detailed analyses of available literature and unpublished data from collections. For each species the following data are quoted: the name of the taxon; synonyms; general distribution; type locality; ecological status; list of locality records; species names used in the cited literature; the distribution map using 10 × 10 km UTM grid squares. Annexes with the locality synonyms used in the examined literature and collection data are enclosed. Altogether this paper presents data from 557 caves, 6 artificial underground structures and 15 other epigean and subterranean localities. A checklist of cave terrestrial isopod taxa in Croatia is composed of 35 species and five subspecies distributed in five families, including 22 Croatian endemic and 20 troglobiotic taxa. The family Trichoniscidae and the subfamily Trichoniscinae are the most representative with 26 and 20 species, respectively. The most represented genus is Alpioniscus with 10 species. The South Croatian Littoral macroregion has the highest number of species and endemics among Croatian macroregions. The most widely distributed species in Croatia are the troglophiles Mesoniscus graniger and Androniscus roseus found in three macroregions. Only four troglobiotic species (Alpioniscus balthasari, A. strasseri, Titanethes albus and T. dahli) are distributed in two macroregions, while the rest are distributed only in single macroregions. All the 40 Croatian cave taxa are distributed in the Dinaric karst area, and only three troglophilic species are found also outside. No Croatian endemic taxa are found outside the Dinaric karst area.

News Article | December 7, 2015

A number of remarkable observations such as an enormous kidney, grooved three-pointed teeth and a huge seasonally present penis are reported in the recent study, conducted by Adrienne Jochum, Naturhistorisches Museum der Burgergemeinde Bern, Switzerland, and her international team of researchers from University of Bern, Switzerland; Shinshu University, Japan; Universitaetsklinikum Giessen und Marburg GmbH, Germany; Justus-Liebig University Giessen, Germany; University of Ljubljana, Slovenia; University of Bern Goethe-University Frankfurt, Germany; Ruhr University Bochum, Germany; Croatian Biospeleological Society, Croatia and University Duisburg-Essen, Germany. The scientists describe these characteristics as adaptations the miniature creatures have acquired in order to survive austerity in the subterranean realm. Usually, adaptations to cave life can include blindness or lack of eyes, loss of pigmentation, sensitivity to changes in temperature and humidity, a high starvation tolerance, or anatomical compromises such as small size and transparent shells. The present study shows that miniscule carychiid subterranean snails have developed huge organs to tolerate the unique conditions of cave life. "Studying adaptations in extreme environments such as those found in snails of subterranean habitats can help us to understand mechanisms driving evolution in these unique habitats," explains the first author. Glassy cave-dwelling snails known only from Northern Spain, the southern Eastern Alpine Arc and the Dinarides might have tiny hearts, but their enormous kidney extends from one to two thirds of the total length of their minute shells. This phenomenon could be explained as an effective mechanism used to flush out large amounts of excess water during flooding seasons in caves. The same impressive creatures have also developed elaborate muscular plates, forming the girdle that surrounds the gastric mill (gizzard) in their digestive tract. The muscular gizzard grinds the grainy stew of microorganisms and fungi the snails find in moist cave mud. These mysterious creatures graze stealthily using an elastic ribbon (radula), aligned with seemingly endless rows of three-pointed, centrally-grooved teeth, as they glide through the depths of karst caves while searching for food and partners. Deprived from the hospitable aspects of life we have grown used to, some of the snails discussed in the present paper have evolved their reproductive system in order to be able to reproduce in the harshest of environments, even when they fail to find a partner for an extended period of time. As a result, not only are these snails protandric hermaphrodites, meaning that they possess male sexual features initially, which later disappear so that the female phase is present, but they have a large retractable, pinecone-shaped penis for instantaneous mating in the summer when mating is most probable. To guarantee offspring, a round sac, known as the receptaculum seminis, stocks sperm received from a partner during a previous mating and allows them to self-inseminate if necessary. Teeth in these cave snails are also described using histology for the first time. They bear a median groove on the characteristic cusps known for the Carychiidae. Sketchy, past dissections provide the current knowledge upon which the findings from this investigation are based. Otherwise, historical descriptions of these tiny snails are only known from empty shells found in samples of cave sediment. The genus Zospeum can only be found alive by inspecting cave walls using a magnifying glass. "Knowledge of their subterranean ecology as well as a "gut feeling" of where they might be gliding about in their glassy shells is necessary to find them," comments Adrienne Jochum. The authors also emphasize that this groundbreaking work is important for biodiversity studies, for biogeographical investigations and for conservation management strategies. Adrienne Jochum and her team investigated the insides of the shells using nanoCT to differentiate species in synchronization with molecular approaches for genetic delimitation. Four well-defined genetic lineages were determined from a total of sixteen Zospeum specimens found in the type locality region of the most common representative, Zospeum isselianum. This investigation is the first integrative study of live-collected Zospeum cave snails using multiple lines of data (molecular analyses, scanning electron microscopy (SEM), nano-computer tomography (nanoCT), and histology. This work is dedicated to the industrious Slovenian malacologist Joze Bole, whose work greatly inspired the present research. Explore further: Life deep down: A new beautiful translucent snail from the deepest cave in Croatia More information: Jochum A, Slapnik R, Klussmann-Kolb A, Páll-Gergely B, Kampschulte M, Martels G, Vrabec M, Nesselhauf C, Weigand AM (2015) Groping through the black box of variability: An integrative taxonomic and nomenclatural re-evaluation of Zospeum isselianum Pollonera, 1887 and allied species using new imaging technology (Nano-CT, SEM), conchological, histological and molecular data (Ellobioidea, Carychiidae). Subterranean Biology 16: 123-165. DOI: 10.3897/subtbiol.16.5758

PubMed | CNRS Systematics, Biodiversity and Evolution Institute, Croatian Biospeleological Society and University of Rouen
Type: Journal Article | Journal: Zootaxa | Year: 2015

The species Heteromurus (Verhoeffiella) absoloni Kseneman, 1938 is redescribed in detail and characterized by its barcode, based on specimens from its type locality in Montenegro. A neotype is designated. Dorsal S-chaetotaxy is given for the first time in the subgenus Verhoeffiella. Chaeta morphology and distribution are thoroughly analyzed, in particular on antennae where 12 chaetal types are recognized. Several morphological features are newly described for the genus and for Heteromurinae. The widely disjunct distribution of the species is approached through morphological and molecular comparison of specimens from the type locality in Montenegro and from the Catalan population. We established that this last record is a new species described here as Heteromurus (Verhoeffiella) gamae sp. nov. New combination is proposed Heteromurus (Verhoeffiella) constantinellus (uri & Lui in Lui, uri & Miti 2007) comb. nov. A table of all species of the subgenus is provided. The taxonomic status of Verhoeffiella and the problems of species discriminations in the subgenus are discussed.

PubMed | Croatian Biospeleological Society, University of Padua, Pensoft Publishers and National Museum of Natural History, Naturrhistorisches Museum Wien and Natural History Museum in London
Type: | Journal: ZooKeys | Year: 2015

A new geophilomorph centipede, Geophilushadesi sp. n., is described from caves in the Velebit Mountain, central Croatia. Together with Geophiluspersephones Foddai & Minelli, 1999, described from Pierre Saint-Martin cave in France, they are the only two remarkably troglomorphic geophilomorphs hitherto known. The new species apparently belongs to a group of Geophilus species inhabiting mainly Western and Southern Europe, with a uniquely modified pretarsus in the second maxillae. Geophilushadesi sp. n. shows unusual traits, some of which commonly found in troglobitic arthropods, including exceptionally elongated antennae, trunk segments and leg claws. The species is described upon specimens found in two caves at a depth below -250 m. Another two specimens apparently belonging to the same species have been recorded in another deep vertical cave at -980 m and -1100 m. The latter represents the worlds deepest record of Chilopoda as a whole.

Antonovic I.,University of Zagreb | Brigic A.,University of Zagreb | Sedlar Z.,University of Zagreb | Bedek J.,Croatian Biospeleological Society | Sostaric R.,University of Zagreb
ZooKeys | Year: 2012

Terrestrial isopods were studied in the Dubravica peat bog and surrounding forest in the northwestern Croatia. Sampling was conducted using pitfall traps over a two year period. Studied peat bog has a history of drastically decrease in area during the last five decades mainly due to the process of natural succession and changes in the water level. A total of 389 isopod individuals belonging to 8 species were captured. Species richness did not significantly differ between bog, edge and surrounding forest. High species richness at the bog is most likely the result of progressive vegetation succession, small size of the bog and interspecific relationships, such as predation. With spreading of Molinia grass on the peat bog, upper layers of Sphagnum mosses become less humid and probably more suitable for forest species that slowly colonise bog area. The highest diversity was found at the edge mainly due to the edge effect and seasonal immigration, but also possibly due to high abundance and predator pressure of the Myrmica ants and lycosid spiders at the bog site. The most abundant species were Trachelipus rathkii and Protracheoniscus politus, in the bog area and in the forest, respectively. Bog specific species were not recorded and the majority of the species collected belong to the group of tyrphoneutral species. However, Hyloniscus adonis could be considered as a tyrphoxenous species regarding its habitat preferences. Most of collected isopod species are widespread eurytopic species that usually inhabit various habitats and therefore indicate negative successive changes or degradation processes in the peat bog. © Ivan Antonović et al.

Lukic M.,Croatian Biospeleological Society | Houssin C.,French Natural History Museum | Deharveng L.,French Natural History Museum
ZooKeys | Year: 2010

Tritomurus veles sp. n. (Tomoceridae) is described from a Croatian cave. It is characterized by troglomorphic features (absence of eyes, reduced pigmentation, slender claw, pointed tibiotarsal tenent hairs) that only compare, among Tomoceridae, to the microendemic species T. falcifer from the Pyrénées. Tritomurus veles also shares with T. falcifer the absence of macrochaetae on head, a presumably non-adaptive character that within Tomoceridae is unique to these two species. Both species have no known epigean relatives in their respective distribution areas and can be considered as relictual. © M. Lukić C. Houssin, L. Deharveng.

Ozimec R.,Croatian Biospeleological Society
Natura Croatica | Year: 2012

Šipun is one of the first mentioned anchialine caves in the world, located in the region of Dubrovnik in Croatia. During more than 100 years of research, over 100 taxa were detected, 38 of them troglobitic, with 18 taxa described from the cave. Some anchialine ecological features were first described in this cave. During recent biospeleological research in the period of 2000-2012 by members of the Croatian Biospeleological Society, the first complete cave sketch was finished, and much ecological and taxonomical research were performed. The cave is endangered due to human activities, but also vulnerable due to the fragility of karst substrate. A management plan, it is suggested, is necessary for adequate cave administration and protection.

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