The genus Megalothorax Willem, 1900 is redefined along with a redescription of the type species M. minimus Willem, 1900 and the description of five new species (M. granulosus, sp. nov., M. nigropunctatus, sp. nov., M. perspicillum, sp. nov., M. svalbardensis, sp. nov. and M. willemi, sp. nov.). We describe and comment on broad sets of discriminating characters for Megalothorax systematics. For the first time, trichobothria are recorded for Neelipleona, probably of generic importance. The described species are provided with DNA data (COI, 16S and 28S) and included in a molecular-based phylogenetic analysis. The traditional distinction between minimus-group and incertus-group is discussed in the light of DNA and morphology components. A key to the worldwide Megalothorax species is provided.
Background Genome sequencing of all known eukaryotes on Earth promises unprecedented advances in biological sciences and in biodiversity-related applied fields such as environmental management and natural product research. Advances in long-read DNA sequencing make it feasible to generate high-quality genomes for many non–genetic model species. However, long-read sequencing today relies on sizable quantities of high-quality, high molecular weight DNA, which is mostly obtained from fresh tissues. This is a challenge for biodiversity genomics of most metazoan species, which are tiny and need to be preserved immediately after collection. Here we present de novo genomes of 2 species of submillimeter Collembola. For each, we prepared the sequencing library from high molecular weight DNA extracted from a single specimen and using a novel ultra-low input protocol from Pacific Biosciences. This protocol requires a DNA input of only 5 ng, permitted by a whole-genome amplification step. Results The 2 assembled genomes have N50 values >5.5 and 8.5 Mb, respectively, and both contain ∼96% of BUSCO genes. Thus, they are highly contiguous and complete. The genomes are supported by an integrative taxonomy approach including placement in a genome-based phylogeny of Collembola and designation of a neotype for 1 of the species. Higher heterozygosity values are recorded in the more mobile species. Both species are devoid of the biosynthetic pathway for β-lactam antibiotics known in several Collembola, confirming the tight correlation of antibiotic synthesis with the species way of life. Conclusions It is now possible to generate high-quality genomes from single specimens of minute, field-preserved metazoans, exceeding the minimum contig N50 (1 Mb) required by the Earth BioGenome Project.
This work proposes a comprehensive review of the morphological features of the Neelipleona, with focus on chaetotaxy. The major contributions to the knowledge of Neelipleona are discussed and new data are presented, acquired from the redescription of Neelides folsomi, Acanthoneelidus pratensis and Neelus murinus. New elements of description are given for Neelus fimbriatus, Megalothorax granulosus, Megalothorax minimus, Megalothorax nigropunctatus, Megalothorax svalbardensis. Juvenile morphology is also taken in consideration with the description of the early instar of Neelides folsomi, Neelus murinus, Megalothorax minimus and Megalothorax nigropunctatus. A nomenclatural framework is proposed to illustrate the descriptions and the hypotheses of homology debated in the paper. Comparative tables are provided to summarize the morphological variations observed in the order. An identification key to the genera is also provided. A set of intriguing and unique characteristics of the Neelipleona were discovered or enlighten such as labral morphology, vibrating antennae in the genus Neelus, special chaetae associated to the secretion of wax rods and pattern of special τ-chaetae.Printed copy of this book is available from US$30.8 plus postage, Click here to order.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.