Session D, 2017 First Place: Under the Sphagnum: An Observational Analysis of the Relationship Between Distance and Ectomycorrhizal Morphotype Diversity in Larix laricina Within Wetland Ecosystems

Ectomycorrhizal fungi (EMF) form a mutualistic symbiosis with host plants by increasing plants’ uptake of nutrients and water. Many tree seedlings are dependent on EMF for successful establishment in nutrient poor areas, such as wetlands. It was hypothesized that EMF morphotype diversity should decrease as the larch saplings get closer to the center of the bog. Larix laricina was chosen as the EMF host of choice due to its abundance in wetlands around Cranberry Lake. Three sample sites were used and a total of nine trees were sampled from three transect lines at each site. The sites were Forsaith’s Bog, Lost Pond Bog, and an unnamed fen. The distances used consisted of trees from the upland-wetland boundary, trees from the wetland interior, and an intermediate zone. These sites were selected because they possessed abundant stands of Larix laricina and met the DBH requirement of our transects. Twenty root tips were taken from each host sapling. EMFs were classified based on morphological features. EMF diversity was calculated for each tree. A regression analysis on the relationship between distance and diversity of morphotypes showed no significant difference (p=0.051). ANOVA analysis revealed no significant difference between the three sites (p=0.060)

New turtle remains from the Late Cretaceous of Monte Alto-SP, Brazil, including cranial osteology, neuroanatomy and phylogenetic position of a new taxon

A high diversity of land vertebrates is known from the Late Cretaceous deposits of the Bauru Basin, Brazil, including at least five turtle taxa, all belonging tothe cladePodocnemidoidae. Some of the richest fossil sites of this basin are in the area of Monte Alto, which yielded several squamate, dinosaur, and crocodyliform taxa. Yet, the single turtle reported so far from this area was only briefly described. Here, we further describe that specimen, a complete but very crushed shell, as well as a partial skull, both found in outcrops of the Adamantina Formation. Comparison of the shell to other podocnemidoid taxa reveals its affinities to Roxochelys wanderleyi, a turtle originally described from that same stratigraphic unit. The comparative description of the skull and its inclusion in a phylogenetic study, supports the proposal of a new taxon representing a lineage (Peiropemydodda) so far known only from the Marília Formation of the Bauru Basin and the early Paleocene of Bolivia. The digitally reconstructed endocast and inner ear of the new taxon were also described, as not previously done fora fossil pleurodire

A small podocnemidoid (Pleurodira, Pelomedusoides) from the Late Cretaceous of Brazil, and the innervation and carotid circulation of side‐necked turtles

Pleurodires are less diverse than cryptodires, together forming the two major lineages of crown turtles. Their fossil record, however, is rich. A particularly large number of fossil pleurodires, many belonging to the Podocnemidoidae, has been recovered from the Upper Cretaceous Bauru Group outcrops of south‐central Brazil. Herein we describe an additional pleurodire from this region, Amabilis uchoensis gen. et sp. nov., based on a partially preserved skull. A. uchoensis is recognized as belonging to the Podocnemidoidae by the small entrance to the antrum postoticum and completely developed cavum pterygoidei, being unique among other non‐podocnemidid podocnemidoids for its medially open fenestra postotica and absent basioccipital–opisthotic contact. Our cladistic analysis places A. uchoensis as a sister taxon to Hamadachelys + other podocnemidoids. We further explore the neuroanatomy of side‐necked turtles with the aid of micro‐computed tomography of specimens of the main pleurodiran lineages. Our data shed light on the different carotid circulation patterns in pleurodires, and we propose new phylogenetic characters to describe the neuroanatomical variation of the group. Optimization of these characters shows two independent acquisitions of a foramen for the palatal branch of the carotid in chelids and podocnemidoids, and a unique loss of the vidian nerve canal in chelids, in turtles in general.Fundação de Amparo à Pesquisa do Estado de São PauloNatural Environment Research Council http://dx.doi.org/10.13039/50110000027

Parallelized Acquisition of Orbitrap and Astral Analyzers Enables High-Throughput Quantitative Analysis

The growing trend toward high-throughput proteomics demands rapid liquid chromatography–mass spectrometry (LC–MS) cycles that limit the available time to gather the large numbers of MS/MS fragmentation spectra required for identification. Orbitrap analyzers scale performance with acquisition time and necessarily sacrifice sensitivity and resolving power to deliver higher acquisition rates. We developed a new mass spectrometer that combines a mass-resolving quadrupole, the Orbitrap, and the novel Asymmetric Track Lossless (Astral) analyzer. The new hybrid instrument enables faster acquisition of high-resolution accurate mass (HRAM) MS/MS spectra compared with state-of-the-art mass spectrometers. Accordingly, new proteomics methods were developed that leverage the strengths of each HRAM analyzer, whereby the Orbitrap analyzer performs full scans with a high dynamic range and resolution, synchronized with the Astral analyzer’s acquisition of fast and sensitive HRAM MS/MS scans. Substantial improvements are demonstrated over previous methods using current state-of-the-art mass spectrometer