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

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  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...

Description of four new Steatoda species (Araneae: Theridiidae) from the Mediterranean region with notes on some related species

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Description of four new Steatoda species (Araneae: Theridiidae) from the Mediterranean region with notes on some related species

Abstract

Four new Steatoda species from the Mediterranean region are diagnosed, described and illustrated: S.
koeni sp. nov. (♂♀, Morocco), S. ingeae sp. nov. (♂♀, Morocco), S. dickjonesi sp. nov. (♂♀, France)
and S. verae sp. nov. (♂♀, Spain). The holotype of S. triangulosa concolor (Caporiacco, 1933) was
examined and found to be a subadult specimen, the subspecies is elevated to species level and S.
concolor stat. nov. is described from both sexes (♂♀, Libya, Tunisia, Algeria), and the female of S.
trianguloides is redescribed. Three new synonyms are proposed: S. moerens (Thorell, 1875) is found
to be a junior synonym of S. latifasciata (Simon, 1873) new syn.; S. incomposita (Denis, 1957) is found
to be a junior synonym of Steatoda albocincta (Lucas, 1846) new syn.; S. albomaculata infuscata
(Schenkel, 1925) is synonymized with S. albomaculata (De Geer, 1778) new syn.; S. venator (Audouin,
1826) is considered a nomen dubium. All Euro-Mediterranean Steatoda species except S. xerophila
Levy & Amitai 1982 are illustrated and a key to the species is provided.

VAN KEER, J., BOSSELAERS, J., OGER, P. (2024). Description of four new Steatoda species (Araneae: Theridiidae) from the Mediterranean region with notes on some related species. Journal of the Belgian Arachnological Society 39(2) supplement: 1-77.