Museum of Boulder

A rarely reported new species of Mimallonidae from Florida, USA, is described. Remarkably, the distinctive new species has not been seen across much of its historical range since the 1960s, and all records come from six somewhat isolated white sand Florida Scrub habitats, one of which is completely destroyed and most others clearly imperiled. DNA barcoding sequences from the disparate populations suggest notable genetic diversity in the few known populations, meaning extirpation of any of them could signal loss of critical population structure of an already narrowly endemic species. Cicinnusalbarenicolus St Laurent, sp. nov. is compared to the only other similar species in North America, C.melsheimeri (Harris in Doubleday), a common denizen of oak forests throughout the eastern United States, including Florida, southern Canada, and the Rocky Mountains. Until its distribution and life history are more well-understood, C.albarenicolus will remain an enigmatic taxon of major conservation concern.

Polar ecosystems are structured and enriched by birds, which nest there seasonally and serve as keystone ecosystem members. Despite the ecological importance of polar birds, the origins of high-latitude nesting strategies remain obscured by a sparse fossil record. We report an extreme-latitude Arctic avialan assemblage from the Prince Creek Formation of Alaska—the northernmost Late Cretaceous terrestrial ecosystem. Numerous three-dimensionally preserved fossils constitute one of the most taxonomically rich Late Cretaceous avialan assemblages, including members of Hesperornithes, Ichthyornithes, and near-crown or crown birds (Neornithes), recording a previously undocumented interval in avialan evolution. Abundant perinatal fossils represent the oldest evidence of birds nesting at polar latitudes, which demonstrates that birds began using seasonal polar environments for breeding during the Cretaceous, long before their modern descendants.

Although infectious diseases play a critical role in population regulation, our knowledge of complex drivers of disease for insects is limited. We conducted a field study on Baltimore checkerspot caterpillars (Euphydryas phaeton), chemical specialists on plants containing iridoid glycosides (IGs), to investigate the roles of host plant, phytochemistry, ontogeny and spatial associations in determining viral prevalence. We analysed individuals for viral presence and loads, quantified leaf IG concentrations from their native and novel host plants, and sequestered IGs in caterpillars. We found proximate caterpillar groups had greater similarity in infection prevalence, with areas of high prevalence indicating viral hotspots. Underlying variation in host plant chemistry corresponded to differences in viral prevalence. Furthermore, we used structural equation modeling to examine causal drivers of infection prevalence and loads. Advanced ontogeny was associated with increased viral prevalence and loads, as well as decreased sequestration of IGs. Infection loads were lower on the novel host plant, but prevalence was slightly higher, partially explained by decreased sequestration of IGs. Altogether, our findings reveal that spatial proximity, ontogeny, host plant species and secondary phytochemistry can all contribute to structuring infection risk, and thus offer insight into causal drivers of disease prevalence in complex plant-insect systems.

Body size declines are a common response to warming via both plasticity and evolution, but variable size responses have been observed for terrestrial ectotherms. We investigate how temperature-dependent development and growth rates in ectothermic organisms induce variation in size responses. Leveraging long-term data for six montane grasshopper species spanning 1,768-3 901 m, we detect size shifts since ~1960 that depend on elevation and species' seasonal timing. Size shifts have been concentrated at low elevations, with the early emerging species (those that overwinter as juveniles) increasing in size, while later season species are becoming smaller. Interannual temperature variation accounts for the size shifts. The earliest season species may be able to take advantage of warmer conditions accelerating growth during early spring development, whereas warm temperatures may adversely impact later season species via mechanisms such as increased rates of energy use or thermal stress. Grasshoppers tend to capitalize on warm conditions by both getting bigger and reaching adulthood earlier. Our analysis further reinforces the need to move beyond expectations of universal responses to climate change to consider how environmental exposure and sensitivity vary across elevations and life histories.

In this study, based on the results of molecular analysis of SSU rRNA and rbcL sequences, we propose the descriptions of two new families in the order Cymbellales. Molecular data demonstrates that diatoms of the genus Encyonema constitute an independent monophyletic clade, which represents a new family described herein – Encyonemataceae fam. nov. Another family introduced in this article, with regards to molecular data, is Witkowskiaceae fam. nov. In our research, it is comprised of three closely related genera – Geissleria, Paraplaconeis and Witkowskia. The results of performed molecular investigation are supported by morphological analysis. Morphological diagnoses of the new families are based on a combination of features: type of valve symmetry, raphe structure, presence and position of stigmata or stigmoids, number and location of apical pore fields and morphology of chloroplast. In addition, we discuss the phylogeny of selected genera of the order Cymbellales. Based on their morphology, 3 and 5 genera are assigned with provisionary position in Encyonemataceae fam. nov. and Witkowskiaceae fam. nov., respectively.

Sarea cirrhendocarpa, a resinicolous fungus, is here described as new to science from two specimens collected in the Indian Peaks Wilderness (Arapaho-Roosevelt National Forest, Colorado, USA) during the summer of 2023, a third specimen from Holy Cross Wilderness (White River National Forest, Colorado, USA) during the summer of 2024, and a fourth specimen from the Kachina Peaks Wilderness (Coconino National Forest, Arizona, USA) that was collected in 1998. The new species is readily distinguished from its closest relative, Sarea resinae, by its larger apothecia, smaller asci, smaller ascospores, and burnt orange hymenium (bicolored towards uppermost portions) among other traits. A phylogeny derived from the nuclear ribosomal internal transcribed spacer (ITS) region suggests that S. cirrhendocarpa is sister to and genetically distinct specimens of Sarea resinae sampled from around the world including North America. These molecular results in combination with the clear morphological differences lead us to propose this as a new species so far only known from the southern Rocky Mountains of North America. This new taxon is placed for the time being within the genus Sarea owing to inconclusive phylogenetic and morphological evidence that would support generic separation within the Sareomycetes. The name Sarea resinae is retained and new combinations for S. klamathica and S. lignicola are provided.

We present a genome assembly from an individualFragum sueziense (the heart cockle; Mollusca; Bivalvia; Cardiida; Cardiidae). The genome sequence is 1,206.1 megabases in span. Most of the assembly is scaffolded into 19 chromosomal pseudomolecules. The mitochondrial genome has also been assembled and is 92.77 kilobases in length. Gene annotation of this assembly on Ensembl identified 70,309 protein-coding genes.

We present a genome assembly from an individual Tridacna derasa (the smooth giant clam; Mollusca; Bivalvia;Cardiida; Cardiidae). The genome sequence is 1,060.2 megabases in span. Most of the assembly is scaffolded into 18 chromosomal pseudomolecules. The mitochondrial genome has also been assembled and is 24.95 kilobases in length. Gene annotation of this assembly on Ensembl identified 19,638 protein coding genes.