Conserving relics from ancient underground worlds: assessing the influence of cave and landscape features on obligate iron cave dwellers from the Eastern Amazon.

The degradation of subterranean habitats is believed to represent a serious threat for the conservation of obligate subterranean dwellers (troglobites), many of which are short-range endemics. However, while the factors influencing cave biodiversity remain largely unknown, the influence of the surrounding landscape and patterns of subterranean connectivity of terrestrial troglobitic communities have never been systematically assessed. Using spatial statistics to analyze the most comprehensive speleological database yet available for tropical caves, we first assess the influence of iron cave characteristics and the surrounding landscape on troglobitic communities from the Eastern Amazon. We then determine the spatial pattern of troglobitic community composition, species richness, phylogenetic diversity, and the occurrence of frequent troglobitic species, and finally quantify how different landscape features influence the connectivity between caves. Our results reveal the key importance of habitat amount, guano, water, lithology, geomorphology, and elevation in shaping iron cave troglobitic communities. While mining within 250 m from the caves influenced species composition, increasing agricultural land cover within 50 m from the caves reduced species richness and phylogenetic diversity. Troglobitic species composition, species richness, phylogenetic diversity, and the occurrence of frequent troglobites showed spatial autocorrelation for up to 40 km. Finally, our results suggest that the conservation of cave clusters should be prioritized, as geographic distance was the main factor determining connectivity between troglobitic communities. Overall, our work sheds important light onto one of the most overlooked terrestrial ecosystems, and highlights the need to shift conservation efforts from individual caves to subterranean habitats as a whole.

An example of the importance of labels and fieldbooks in scientific collections: A freshwater sponge misunderstood for a marine new genus and species.

The demosponge genus Crelloxea Hechtel, 1983 was created to allocate a single species, Crelloxea spinosa Hechtel, 1983, described based on specimens collected by Jacques Laborel in northeastern Brazil in 1964 and deposited at the Porifera Collection of the Yale Peabody Museum. The genus Crelloxea was originally defined as "Crellidae with dermal and interstitial acanthoxeas and acanthostrongyles, with skeletal oxea and without microscleres or echinators" (Hechtel, 1983). Crelloxea was allocated in the marine sponge family Crellidae (Order Poecilosclerida), which is characterized by a tangential crust of spined ectosomal spicules (oxeas, anisoxeas or styles), a choanosomal plumose skeleton of smooth tornotes, sometimes a basal skeleton of acanthostyles erect on the substrate, microscleres usually arcuate chelae or absent, and surface with areolated pore fields (van Soest, 2002). Nowadays, Crelloxea is considered a junior synonym of Crella (Grayella) Carter, 1869 (van Soest, 2002; van Soest et al., 2015).

Biodiversity of freshwater sponges (Porifera: Spongillina) from northeast Brazil: new species and notes on systematics.

Systematics and distribution of freshwater sponges is still poorly understood worldwide. This may be due to the scarcity of records, and the limited information about morphological traits used for taxonomy. Brazil has reportedly high species richness in the Neotropical Region; however, this diversity is likely to be significantly underestimated given that there are still many unexplored and poorly sampled areas, mainly in the north and northeast regions. We present here new locality records and taxonomic notes on three families and ten species of freshwater Porifera from northeast Brazil: Metaniidae (1), Potamolepidae (2) and Spongillidae (7). A new species of freshwater sponge is described here (Ephydatia caatingae sp.nov.). Additional notes on the systematics and biogeography of most of these species are also presented.