Big Spider, Big Genome: Chromosome-level genome of a North American tarantula (Aphonopelma marxi) and comparative genomics across 300 million years of spider evolution

Posted by
  Image Credit: WikiCommons Big Spider, Big Genome: Chromosome-level genome of a North American tarantula (Aphonopelma marxi) and comparative genomics across 300 million years of spider evolution Abstract The comparison of chromosome-level genomes allows biologists to investigate new axes of organismal evolution. Spiders comprise a significant proportion of known arachnid diversity, with many complex morphologies and unique natural histories, yet comparative genomics in spiders has been limited due to the number of available genomes. We present a de novo chromosomal reference genome of a mature male tarantula, Aphonopelma marxi, and comparatively examine spider genome evolution across the Order Araneae. Using PacBio HiFi and Hi-C sequencing, the final 6.5 Gb assembly consists of 17 autosomes, 1 X chromosome, and 127 unplaced scaffolds, with an N50 of 370 Mb and Arachnida (odb10; 2934 genes) BUSCO of 96.7%. By comparing 20 additional spider genomes from 15 families, we find mygalomo...

Precision Lost with Complexity: On an Extraordinary New Species of Pholcidae (Araneae, Smeringopinae) from Western DR Congo

Posted by

 

Precision Lost with Complexity: On an Extraordinary New Species of Pholcidae (Araneae, Smeringopinae) from Western DR Congo

Abstract

A remarkable new pholcid spider species is described from the Democratic Republic of the Congo: Smeringopina polychila sp. nov. The male is distinguished by a unique and previously undocumented structure, here termed the “parachila”, which has not been observed in any other spider to date. The description is complemented by high-quality illustrations, including detailed drawings, photographs, micro-CT scans, and 3D reconstructions of the genitalia and the newly discovered male structure. Remarkable intraspecific variations, both somatic and genitalic, in males are also highlighted and discussed. A phylogenetic analysis based on the cytochrome c oxidase subunit I, 16S ribosomal RNA and histone H3 gene fragments is presented to tentatively place the new species into an existing phylogenetic framework. The results of the molecular analyses confirm that the new species belongs to the subfamily Smeringopinae and is nested within the genus Smeringopina Kraus, 1957.

Henrard, A., Jocqué, R., Smitz, N., & Grignet, V. (2025). Precision Lost with Complexity: On an Extraordinary New Species of Pholcidae (Araneae, Smeringopinae) from Western DR Congo. Taxonomy, 5(4), 57. https://doi.org/10.3390/taxonomy5040057