First fossil species of family Hyidae (Arachnida: Pseudoscorpiones) confirms 99 million years of ecological stasis in a Gondwanan lineage.

Burmese amber preserves a diverse assemblage of Cretaceous arachnids, and among pseudoscorpions (Arachnida: Pseudoscorpiones), ten species in five families have already been named. Here, we describe a new fossil species from Burmese amber in the pseudoscorpion family Hyidae, providing detailed measurements, photographs and 3D-models from synchrotron scanning. Based on morphology, the new fossil, Hya fynni sp. nov. is placed in the genus Hya, and is nearly identical to extant species in the genus, except for the position of trichobothrium est on the pedipalpal chela, thereby indicating extreme morphological stasis in this invertebrate lineage over the last 99 million years. Hya fynni represents the first described fossil species in Hyidae, and the third described Burmese fossil in the superfamily Neobisioidea. It also joins the garypinid, Amblyolpium burmiticum, in representing the oldest fossil records for extant pseudoscorpion genera. Considering proposed divergence dates, the newly described fossil species bolsters a Gondwanan origin for Hyidae, and provides evidence for the "Late Jurassic Rifting" hypothesis for the Burma Terrane, in which this landmass rifted from Gondwana in the Late Jurassic and collided with Eurasia by the Cretaceous/Eocene. Like Hya species today, H. fynni likely inhabited humicolous microhabitats in tropical forests on the Burma Terrane, supporting ecological niche stasis for this family since the Mesozoic.

A new pseudoscorpion genus (Garypinoidea: Garypinidae) from the Eocene supports extinction and range contraction in the European paleobiota.

During the Paleogene, the Holarctic experienced drastic climatic oscillations, including periods of extensive glaciation. These changes had a severe impact on both the flora and fauna causing widespread extinction and range shifts with some taxa retreating to refugia in the Mediterranean Basin. Here we provide evidence for this hypothesis using fossils from the pseudoscorpion family Garypinidae Daday, 1889 (Arachnida: Pseudoscorpiones). This family comprises 21 extant genera from all continents except Antarctica but is restricted to low mid-latitudes (<44°N) in the Northern Hemisphere. We provide the second record of garypinids from the European succinite ambers of the Eocene by describing the first extinct genus in Garypinidae, Baltamblyolpium gen. nov., which includes two species: Baltamblyolpium gizmotum sp. nov. from Baltic amber and Baltamblyolpium grabenhorsti sp. nov. from Bitterfeld amber. The new genus exhibits a morphology that closely resembles Neoamblyolpium Hoff, 1956 from western North America and the genus Amblyolpium Simon, 1898, which is widespread but includes taxa restricted to Mediterranean refugia in Europe. The discovery of a new fossil genus of Garypinidae from Europe confirms that the family was found at more northerly latitudes during the Eocene, however, extinction and range contraction resulted in their present-day relictual distribution in southern Europe like many other lineages that once thrived in the European "Baltic amber forest" of the Eocene.

Atmospheric CO2 forcing on Mediterranean biomes during the past 500 kyrs.

There is growing concern on the survival of Mediterranean forests under the projected near-future droughts as a result of anthropogenic climate change. Here we determine the resilience of Mediterranean forests across the entire range of climatic boundary conditions realized during the past 500 kyrs based on continuous pollen and geochemical records of (sub)centennial-scale resolution from drillcores from Tenaghi Philippon, Greece. Using convergent cross-mapping we provide empirical confirmation that global atmospheric carbon dioxide (CO2) may affect Mediterranean vegetation through forcing on moisture availability. Our analysis documents two stable vegetation regimes across the wide range of CO2 and moisture levels realized during the past four glacial-interglacial cycles, with abrupt shifts from forest to steppe biomes occurring when a threshold in precipitation is crossed. Our approach highlights that a CO2-driven moisture decrease in the near future may bear an impending risk for abrupt vegetation regime shifts prompting forest loss in the Mediterranean region.

XRF core scanning yields reliable semiquantitative data on the elemental composition of highly organic-rich sediments: Evidence from the Füramoos peat bog (Southern Germany).

X-ray fluorescence core scanning (XRF-CS) has become a standard tool in paleoenvironmental studies. Allowing rapid, inexpensive and non-destructive analysis of the elemental composition of sediment cores at high spatial resolution, it is ideally suited for the reconstruction of short-term climatic change. However, its applicability to cores consisting of peat and other highly organic-rich sediments has yet remained poorly explored. We have therefore investigated the application of XRF-CS to two cores consisting of ombrotrophic peat and of fen peat and organic-rich muds of Late Glacial-Holocene and Eemian age, respectively, from a peat bog in Southern Germany using an Avaatech 4th-generation XRF core scanner. The XRF-CS-derived distributions of elements widely used in (paleo)environmental research (i.e., Al, Ca, Fe, K, Mg, Mn, S, Si, and Ti) were systematically compared to the results of inductively coupled plasma optical emission spectrometry analyses. For the Late Glacial-Holocene peat core, XRF-CS yielded reliable semiquantitative data for the majority of the investigated elements (i.e., Ca, Fe, K, Mn, S, Si, and Ti), with R2 ≥ 0.5. XRF-CS of the Eemian fen peat and organic-rich muds yielded reliable data for Al, K, S, and Ti (R2 ≥ 0.5) and, to a lesser extent, for Fe (R2 = 0.46). and Si (R2 = 0.25). This indicates that XRF-CS allows to semiquantitatively reconstruct the distribution of the majority of paleoclimatically relevant elements in peat and other highly organic-rich sediments. Hence, XRF-CS is well suited to complement the analytical toolbox for the paleoenvironmental study of such sediments.

Miocene honey bees from the Randeck Maar of southwestern Germany (Hymenoptera, Apidae).

The Miocene Randeck Maar (southwestern Germany) is one of the only sites with abundant material of fossil honey bees. The fauna has been the focus of much scrutiny by early authors who recognized multiple species or subspecies within the fauna. The history of work on the Randeck Maar is briefly reviewed and these fossils placed into context with other Tertiary and living species of the genus Apis Linnaeus (Apinae: Apini). Previously unrecorded specimens from Randeck Maar were compared with earlier series in an attempt to evaluate the observed variation. A morphometric analysis of forewing venation angles across representative Recent and Tertiary species of Apis as well as various non-Apini controls was undertaken to evaluate the distribution of variation in fossil honey bees. The resulting dendrogram shows considerable variation concerning the wing venation of Miocene Apini, but intergradation of other morphological characters reveals no clear pattern of separate species. This suggests that a single, highly variable species was present in Europe during the Miocene. The pattern also supports the notion that the multiple species and subspecies proposed by earlier authors for the Randeck Maar honey bee fauna are not valid, and all are accordingly recognized as Apis armbrusteri Zeuner.