In comparison to biodiversity on Earth's surface, subterranean biodiversity has largely remained concealed. The olm (Proteus anguinus) is one of the most enigmatic extant cave inhabitants, and until ...now little was known regarding its genetic structure and evolutionary history. Olms inhabit subterranean waters throughout the Dinaric Karst of the western Balkans, with a seemingly uniform phenotypic appearance of cave‐specialized traits: an elongate body, snout and limbs, degenerated eyes and loss of pigmentation (“white olm”). Only a single small region in southeastern Slovenia harbours olms with a phenotype typical of surface animals: pigmented skin, eyes, a blunt snout and short limbs (“black olm”). We used a combination of mitochondrial DNA and genome‐wide single nucleotide polymorphism data to investigate the molecular diversity, evolutionary history and biogeography of olms along the Dinaric Karst. We found nine deeply divergent species‐level lineages that separated between 17 and 4 million years ago, while molecular diversity within lineages was low. We detected no signal of recent admixture between lineages and only limited historical gene flow. Biogeographically, the contemporaneous distribution of lineages mostly mirrors hydrologically separated subterranean environments, while the historical separation of olm lineages follows microtectonic and climatic changes in the area. The reconstructed phylogeny suggests at least four independent transitions to the cave phenotype. Two of the species‐level lineages have miniscule ranges and may represent Europe's rarest amphibians. Their rarity and the decline in other lineages call for protection of their subterranean habitats.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Subterranean animals are known for their highly evolved phenotypes. They are eyeless, depigmented and possess elongated appendages compared to their surface relatives. Increased antenna and leg ...length of cave species has traditionally been explained as a consequence of selection for non‐visual senses and increased food‐finding ability in an environment low in energy. Variation in appendage length between cave species is usually thought to result from differences in time since the colonization of the subterranean habitat. In this study, we analyzed appendage length variation in the Dinaric amphipod species Niphargus croaticus. Relative length of appendages varied substantially among populations. Using multilocus phylogenetic analysis, we showed that the species is nested within highly specialized N. steueri species complex and rejected the time hypothesis. Next, we explored the effects and strength of two environmental factors, water flow and presence of a competing species, N. subtypicus. Populations in caves with flowing water had shorter appendages than populations in cave lakes. Presence of the competing sister species did lead to longer appendages in stagnant water, but had no effect in flowing water. Abiotic factors had a stronger effect than biotic factors, but their relative strength differed among appendage pairs. High variation in appendage length between adjacent population shows that the morphology of cave arthropods is changing quickly and therefore cannot be used to predict species age. Rather than being a general adaptation to cave life, long appendages seem to be associated with the absence of water flow as well as character displacement when in sympatry with ecologically similar competing species.
We critically address the question of antenna and leg length in cave arthropods, an important trait in the study of convergent evolution. This classical cave‐related trait is almost unanimously considered as adaptation to the lightless and energy‐low cave environment. However, we demonstrate that variation in appendage length can be explained by selective factors that are not peculiar to the subterranean environment, such as water flow velocity and presence of competing species.
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BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Two Niphargus species, Niphargus khayyami sp. nov. and Niphargus khwarizmi sp. nov., are morphologically analysed and described. Both species are found in western Iran, which represents the ...easternmost border of the distributional area for this subterranean amphipod genus. We were unable to attribute N. khayyami sp. nov. to any of 80 Niphargus species that were analysed for 28S ribosomal DNA sequences; sequencing of N. khwarizmi sp. nov. failed. Niphargid findings from west Asia recorded in 5 years imply that almost one half of the range of this large freshwater amphipod genus is still unexplored. http://www.zoobank.org/urn:lsid:zoobank.org:pub:9E9E7CC9-83E2-419F-A394-57197305E1EF
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BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The remarkably discontinuous distribution of the cave shrimp genus
Troglocaris in South France, West Balkans, and West Caucasus has long been considered a biogeographic enigma. To solve it, its ...phylogeny was reconstructed by analyzing sequences from two mitochondrial (cytochrome oxidase I and 16S rRNA) and one nuclear gene (28S rRNA) using maximum likelihood, parsimony and Bayesian inference. The genus was found to be polyphyletic because the French taxon
T. inermis had no direct common ancestry with other
Troglocaris taxa but was sister to the epigean freshwater atyid
Dugastella valentina. All other
Troglocaris species constituted a well-supported monophylum, the second cave shrimp genus
Spelaeocaris nested within. The monophylum had a well-defined structure: (1) a clade restricted to the Dinaric area of the Western Balkans containing the type species
T. anophthalmus along with some unnamed species, and (2) a geographically mixed clade split between the Caucasian
T. kutaissiana species complex on one, and
T. hercegovinensis,
S. pretneri, plus an unnamed taxon on the other side. It was surprising to find the dichotomy between the Caucasian and one of the West-Balkan lineages so low in the phylogenetic hierarchy of the genus. Taking into account molecular rates of other decapods, we tentatively dated this split at 6–11
Myr. This time is in agreement with the brackish and freshwater phase of the Paratethys thus allowing for a freshwater common ancestor of Caucasian and Dinaric cave shrimps. This would weaken the marine relicts hypothesis that has often been invoked to explain the distribution of freshwater cave species with close marine relatives.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Of the approximately 350 described species of serpulid polychaetes, only Marifugia cavatica inhabits fresh water. It is distributed in ground waters of the Dinaric Karst in northeastern Italy, ...Slovenia, Croatia, and Bosnia and Hercegovina. Five other serpulid species, comprising the genus Ficopomatus, are found in brackish water locations worldwide; otherwise serpulids are all marine organisms. We re-describe M. cavatica and examine the fine structure of its chaetae with SEM as well as summarise its distribution. The morphology of Marifugia provides an ambiguous indication of its phylogenetic relationships, thus DNA sequence data was also used. Phylogenetic analysis of nuclear rDNA 18S and 28S sequences using maximum parsimony, maximum likelihood and Bayesian analyses places Marifugia as a sister group to a clade of brackish-water Ficopomatus species. Osmoconformity and penetration into non-marine waters hence appears to have taken place once in the evolutionary history of Serpulidae. The transition to a subterranean environment may have occurred via ancestral marine shallow water to intertidal or estuarine species (like Ficopomatus) that evolved the necessary physiological mechanisms to withstand low salinity and then penetrated into freshwater caves via surface lakes.
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Velkovrhia enigmatica is the only freshwater hydrozoan living exclusively in groundwater. It is endemic to the Dinarides in the Balkan Peninsula, where it has been known from four caves only. Here we ...report on a new V. enigmatica population from cave Logarček near Laze in southwestern Slovenia. In addition, after almost 30 years since its last recorded presence, we confirm the current presence of numerous V. enigmatica individuals in the type locality, Planinska jama. Individuals from the two caves were morphologically different: polyps from the type locality had 4–9 tentacles, while the ones from Logarček had 14–36 tentacles. The mitochondrial DNA sequences in populations from both caves did not differ. Additional research is needed to provide further insights into species taxonomy, biology and distribution.
Niphargus steueri (Niphargidae) comprises a complex of four subspecies (N. s. steueri, N. s. kolombatovici, N. s. subtypicus, and N. s. liburnicus), the morphology and distribution of which have been ...poorly known until now. New diagnostic characters of the species and its four subspecies are presented and illustrated. The species is distributed along the major part of the Dinaric Karst, between Slovenia in the northwest and Bosnia and Herzegovina in the southeast. The distribution of the four subspecies approximately resembles the distribution of the evolutionary lineages of the subterranean amphibian Proteus anguinus and the Dinaric lineage of the cave shrimp Troglocaris agg. anophthalmus. Niphargus s. steueri is restricted to the Istran Peninsula; N. s. subtypicus is distributed in southeast Slovenia and northwest Croatia; N. s. liburnicus is known from two disjunctive localities, one on the island of Krk (Croatia) and the other in Gorizia (Italy); and N. s. kolombatovici is restricted to Dalmacija and Herzegovina. The somewhat variable putative synapomorphies of N. steueri probably suggest that the group is old and that the present distribution pattern is a result of historical events, possibly events in the Miocene Dinaride Lake system. Two populations of N. s. kolombatovici and one population of N. s. subtypicus deviate from the general distributional pattern and may belong to cryptic taxa that cannot be distinguished on the basis of morphology. Both hypotheses corroborate with the estimated times of divergence and with the number of independent lineages in the similarly distributed but unrelated stygobionts Proteus and Troglocaris.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
During the survey of butterfly fauna of Dalmatian mountains in the last years, Proterebia afra dalmata (Godart, 1824) was found on several new sites, including the first records of this subspecies at ...higher altitudes (Postak, Svilaja, Promina, Kamesnica and Dinara Mts.). In this paper we present a much more complete picture of the distribution of this presumably rare butterfly and discuss its altitudinal distribution. The species was found at altitude of almost 1500 m, therefore the characterization of the subspecies as a lowland butterfly can be dismissed.Original Abstract: Med raziskavami favne metuljev dalmatinskih hribov v zadnjih letih smo vrsto Proterebia afra dalmata (Godart, 1824) nasli na vec novih lokalitetah, vkljucno s prvimi najdbami te podvrste na visjih nadmorskih visinah (gore Postak, Svilaja, Promina, Kamesnica in Dinara). V clanku predstavljamo veliko popolnejso sliko razsirjenosti tega domnevno redkega metulja in razpravljamo o njegovi visinski razsirjenosti. Vrsto smo nasli na skoraj 1500 m visine, zato moramo zavreci opredelitev vrste kot nizinske.
ABSTRACT
Subterranean ecosystems are among the most widespread environments on Earth, yet we still have poor knowledge of their biodiversity. To raise awareness of subterranean ecosystems, the ...essential services they provide, and their unique conservation challenges, 2021 and 2022 were designated International Years of Caves and Karst. As these ecosystems have traditionally been overlooked in global conservation agendas and multilateral agreements, a quantitative assessment of solution‐based approaches to safeguard subterranean biota and associated habitats is timely. This assessment allows researchers and practitioners to understand the progress made and research needs in subterranean ecology and management. We conducted a systematic review of peer‐reviewed and grey literature focused on subterranean ecosystems globally (terrestrial, freshwater, and saltwater systems), to quantify the available evidence‐base for the effectiveness of conservation interventions. We selected 708 publications from the years 1964 to 2021 that discussed, recommended, or implemented 1,954 conservation interventions in subterranean ecosystems. We noted a steep increase in the number of studies from the 2000s while, surprisingly, the proportion of studies quantifying the impact of conservation interventions has steadily and significantly decreased in recent years. The effectiveness of 31% of conservation interventions has been tested statistically. We further highlight that 64% of the reported research occurred in the Palearctic and Nearctic biogeographic regions. Assessments of the effectiveness of conservation interventions were heavily biased towards indirect measures (monitoring and risk assessment), a limited sample of organisms (mostly arthropods and bats), and more accessible systems (terrestrial caves). Our results indicate that most conservation science in the field of subterranean biology does not apply a rigorous quantitative approach, resulting in sparse evidence for the effectiveness of interventions. This raises the important question of how to make conservation efforts more feasible to implement, cost‐effective, and long‐lasting. Although there is no single remedy, we propose a suite of potential solutions to focus our efforts better towards increasing statistical testing and stress the importance of standardising study reporting to facilitate meta‐analytical exercises. We also provide a database summarising the available literature, which will help to build quantitative knowledge about interventions likely to yield the greatest impacts depending upon the subterranean species and habitats of interest. We view this as a starting point to shift away from the widespread tendency of recommending conservation interventions based on anecdotal and expert‐based information rather than scientific evidence, without quantitatively testing their effectiveness.
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