Search

The Dinaric Karst is a global hotspot for subterranean diversity, with two distinct peaks of species richness in the northwest and southeast, and an area of a lower species richness in the central part. In this article, we present a species list and describe the ecological conditions of the Lukina jama–Trojama cave system, located in the central part of the Dinaric Karst. This cave system is the deepest and one of the most logistically challenging cave systems sampled so far in the Dinaric Karst. Repeated sampling resulted in a list of 45 species, including 25 troglobionts, 3 troglophiles, 16 stygobionts, and 1 stygophile. Most of the recorded species are endemic to the Velebit Mountain, while three species are endemic to the Lukina jama–Trojama cave system. Within the system, species richness peaks in the deepest third of the cave, most likely reflecting the harsh ecological conditions in the upper parts, including ice, cold winds, and occasional waterfalls. Milder and more stable deeper parts of the cave contain a rich subterranean species community, part of which is associated with two very distinct aquatic habitats, the cave hygropetric and the phreatic zone. The newly recognized hotspot of subterranean biodiversity in the central Dinaric Karst, which has emerged between the two known centers of biodiversity, further highlights the species richness in large cave systems, but also challenges the diversity patterns in the Dinaric Karst overall. [ABSTRACT FROM AUTHOR]

The genus Harpactea Bristowe, 1939 (Araneae, Dysderidae) is one of the most diverse and abundant components of the Mediterranean ground-dwelling spider fauna. However, the taxonomic boundaries of the genus are unclear and its monophyly has been questioned, yet never tested, in a quantitative framework. The only taxonomic revisions in the genus trace back to the 1960s–1990s, and most subsequent work has consisted of single species descriptions. Part of the confusion surrounding the genus and species groups delimitations have to do with the lack of a standardized nomenclature for diagnostic structures based on explicit homology statements. Here we use the description of new species of Harpactea to propose a set of homologies in the male and female genitalia and a standardized nomenclature for those structures. We formally describe three new Harpactea species: H. salvatorei sp. nov., from a cave in the north-eastern Italian Alps, and H. damini sp. nov. and H. mateparlovi sp. nov. from different caves on the Biokovo Mountain and surroundings in Croatia. All the new taxa belong to the lepida species group. In addition, we use a multilocus target gene approach to provide the first hypothesis on the internal phylogenetic structure of the genus Harpactea and the subfamily Harpacteinae, which includes representatives of all currently accepted species groups in the genus and genera in the subfamily. Our results support the close affinities of the species here described but reject the monophyly of both Harpactea and some of the species groups proposed in the literature. [ABSTRACT FROM AUTHOR]

The genus Troglocladius Andersen, Baranov et Hagenlund, gen. n. is erected based on T. hajdi Andersen, Baranov et Hagenlund, sp. n. collected at 980 m depth in the Lukina jama—Trojama cave system in Croatia. Morphological features such as pale color, strongly reduced eyes and very long legs make it a typical cave animal. Surprisingly, it has also retained large wings and appears to be capable of flight which would make T. hajdi the first flying troglobiont worldwide, disproving previous beliefs that bats are the only animals capable of flying in complete darkness. Morphologically the new species does not readily fit within any described genus, but shares characteristics with genera both in the tribes “Metriocnemini” and “Orthocladiini”. Bayesian molecular phylogenetic analysis using the markers COI, 18S rDNAs, 28S rDNA, CADI, and CADIV groups it with the genera Tvetenia, Cardiocladius and Eukiefferiella in the tribe “Metriocnemini”. Troglocladius hajdi may be parthenogenetic, as only females were collected. The discovery confirms the position of the Dinaric arch as a highly important hotspot of subterranean biodiversity. [ABSTRACT FROM AUTHOR]