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Abstract Spiny lizards (genus Sceloporus) have long served as important systems for studies of behavior, thermal physiology, dietary ecology, vector biology, speciation, and biogeography. The western fence lizard, Sceloporus occidentalis, is found across most of the major biogeographical regions in the western United States and northern Baja California, Mexico, inhabiting a wide range of habitats, from grassland to chaparral to open woodlands. As small ectotherms, Sceloporus lizards are particularly vulnerable to climate change, and S. occidentalis has also become an important system for studying the impacts of land use change and urbanization on small vertebrates. Here, we report a new reference genome assembly for S. occidentalis, as part of the California Conservation Genomics Project (CCGP). Consistent with the reference genomics strategy of the CCGP, we used Pacific Biosciences HiFi long reads and Hi-C chromatin-proximity sequencing technology to produce a de novo assembled genome. The assembly comprises a total of 608 scaffolds spanning 2,856 Mb, has a contig N50 of 18.9 Mb, a scaffold N50 of 98.4 Mb, and BUSCO completeness score of 98.1% based on the tetrapod gene set. This reference genome will be valuable for understanding ecological and evolutionary dynamics in S. occidentalis, the species status of the California endemic island fence lizard (S. becki), and the spectacular radiation of Sceloporus lizards.
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This content will become publicly available on February 19, 2026
A chromosome-length genome assembly for the Pismo clam, Tivela stultorum , a long-lived bivalve species severely impacted by overfishing
Abstract The Pismo clam, Tivela stultorum, is an ecologically and economically important species inhabiting sandy beaches and subtidal zones in central and southern California, USA, and northern Baja California, Mexico. This long-lived venerid clam species is of great management, cultural and conservation interest in California where it was harvested for centuries by indigenous people and then nearly extirpated by intense commercial and recreational overfishing in the mid-1900s. A recreational fishery continues today in California; however, T. stultorum faces pressure from poaching, overharvest, and the loss of sandy beaches from rising sea levels and beach erosion. Understanding the susceptibility and resilience of Pismo clams to these pressures is essential for their conservation. We used Pacific Biosciences HiFi long sequencing reads and Dovetail Omni-C proximity reads to assemble a highly contiguous genome of 763 Mb. The genome had a contig N50 of 13 Mb and a scaffold N50 of 38 Mb with a BUSCO completeness score of 95%. Most of the genome sequences (96%) were contained in 19 scaffolds at least 10MB long, consistent with prior evidence that venerid clam genomes are composed of 19 autosomes. This reference genome will enable a more complete understanding of the ecology and evolutionary dynamics of T. stultorum via population genomic analyses, which will help assess risks from climate, fishing, environmental change, and susceptibilities due to life history. Our goal is to better support the continued recovery, informed management and conservation, and future persistence of T. stultorum, a long-lived and highly valued clam species.
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- Award ID(s):
- 2425417
- PAR ID:
- 10636457
- Editor(s):
- Meyer, Rachel
- Publisher / Repository:
- Oxford
- Date Published:
- Journal Name:
- Journal of Heredity
- Volume:
- 116
- Issue:
- 5
- ISSN:
- 0022-1503
- Page Range / eLocation ID:
- 680 to 690
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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