Francisco W. Welter-Schultes

The paleogeography of late Neogene central Crete inferred from the sedimentary record combined with Albinaria land snail biogeography

Abstract Phylogenetic and geographic relations of recent land organisms often agree with results from tectonical and paleogeographic reconstructions. In the Hellenic island arc (Greece), Albinaria land snails (Gastropoda Pulmonata: Clausiliidae) are used to provide paleogeographical information in a combined analysis of their present distributional ranges and the sedimentary record. Late Tertiary (Neogene) islands in the region of present-day Crete existed for 6–9xa0Myear, before the arc was uplifted 3–2xa0Myear ago (Pliocene). The Albinaria fauna of Crete is known to be relictual. In central Crete (an area of 3800xa0km2), the distributional ranges of 15 parapatrically dispersed Albinaria species were determined. Based on differences in their ecological behavour, the species are subdivided into two groups: group 1 exclusively living on pre-Neogene substrate is believed to have largely conserved pre-Pliocene ranges; and group 2 partly living on Neogene, partly on pre-Neogene substrates is assumed to have occupied the land which appeared after late Neogene uplift events. Together with the sedimentary record, Albinaria helps to reconstruct the dynamic paleogeographic developments and block movements in central Crete since the Serravallian. The conclusions imply: (1) that some of the involved populations have been separated from each other for up to 11xa0Myear; and (2) that providing information on paleoislands, recent land snails may contribute to geoscientific questions concerning the rate and timing of uplift and erosion.

Predator-prey interactions between shell-boring beetle larvae and rock-dwelling land snails.

Drilus beetle larvae (Coleoptera: Elateridae) are specialized predators of land snails. Here, we describe various aspects of the predator-prey interactions between multiple Drilus species attacking multiple Albinaria (Gastropoda: Clausiliidae) species in Greece. We observe that Drilus species may be facultative or obligate Albinaria-specialists. We map geographically varying predation rates in Crete, where on average 24% of empty shells carry fatal Drilus bore holes. We also provide first-hand observations and video-footage of prey entry and exit strategies of the Drilus larvae, and evaluate the potential mutual evolutionary impacts. We find limited evidence for an effect of shell features and snail behavioral traits on inter- and intra-specifically differing predation rates. We also find that Drilus predators adjust their predation behavior based on specific shell traits of the prey. In conclusion, we suggest that, with these baseline data, this interesting predator-prey system will be available for further, detailed more evolutionary ecology studies.

Spatial variations in Albinaria terebra land snail morphology in Crete (Pulmonata: Clausiliidae): constraints for older and younger colonizations?

Abstract A spatial approach was employed to test whether the conchological differentiation of the Recent land snail Albinaria terebra from southern central Crete (Greece) is decreased in areas that have been more recently colonized by the species. The eastern Mediterranean genus Albinaria has produced more than 120 species, probably in pre-Tortonian events of radiation. A. terebra occupies a compact range of 550 km2 consisting partly of late Cenozoic deposits of different ages, partly of pre-Cenozoic formations. The morphological study was based on 300 samples distributed over the entire range of the species. Shell size, shape, whorls, and teleoconch rib densities exhibited no evident correlation with environment but were subjected to considerable spatial variations. The differentiation, determined as the difference of the mentioned shell parameters between one population and another population 2–4 km distant, was found to increase continuously with the time (1–12 Myr) the land has been exposed to air. The populations with the highest degrees of spatial variation came from two areas that have never been submerged in the late Cenozoic, possibly the oldest populations of the species. It is plausible that the other areas were colonized by range expansion after late Neogene periods of tectonic uplift. The results are consistent with previous conclusions derived from molecular studies setting the radiation of Albinaria prior to the Tortonian and imply that we might be in possession of a new tool to detect information on the phylogeographic history of land snail species.

Case 3548 A proposal for the treatment of Mémoires pour servir à l’histoire des insectes by De Geer (1752–1778) and the additional volume by Retzius (1783)

Abstract. We analysed the eight volumes of Mémoires pour servir à lhistoire des insectes, published between 1752 and 1778 by De Geer, and an additional volume published by Retzius in 1783. We found that none of these works was consistently binominal. A great number of names of taxa of many insect and other arthropod groups that were established in those works are currently widely accepted and used, and regarding them as unavailable would cause an unnecessary amount of confusion and taxonomical instability. De Geer (1752) is a pre-Linnaean publication and the two parts of volume 2 (1771a, b) did not contain any Latin names. We propose that the works published by De Geer (1773, 1774, 1775, 1776, 1778) and Retzius (1783) be ruled to be available as binominal works and 140 polynominal names mentioned therein be suppressed, mostly for being identified as polynominal. Among the polynominal names included in these volumes were the very commonly used names for human lice (Pediculus humanus capitis and P. humanus corporis) which De Geer regarded as different species, not as subspecies of P. humanus. We suggest that P. h. capitis be considered available and that P. h. corporis be suppressed (the latter being commonly regarded as a synonym of P. h. humanus Linnæus, 1758 in modern biology and medicine). Generic names established as compound words connected with a hyphen should generally be regarded as binominal and available, but we propose to suppress De Geers spider names Aranealupus, Araneaphalangium and Araneacancroides for the purposes of the Principle of Priority, but not for those of the Principle of Homonymy.