Joining the dark side: waterfall spiders in subterranean habitats, with the description of a new genus and two new species from Brazil (Araneae: Trechaleidae)

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  Joining the dark side: waterfall spiders in subterranean habitats, with the description of a new genus and two new species from Brazil (Araneae: Trechaleidae) Abstract Trechaleidae is a family of spiders often recognized by its semiaquatic species, but its diversity extends beyond these well-known examples. In this study, we describe Troglotrechalea gen. nov. , a new genus with two novel species, T. faleroae spec. nov. and T. agorai spec. nov. , found exclusively in subterranean habitats within karst formations in central and southeastern Brazil. Both species exhibit pale coloration, but unmodified eyes and legs if compared to other species in the family. The slight degree of troglomorphism, along with their geographic and habitat records, suggests that these species are restricted to hypogean habitats, although they probably move through epigean habitats. Additionally, we report in detail the occurrence of the trechaleid genera Enna O. Pickard-Cambridge, 1897, Heidrunea Brescovi...

Oligopeptides analysis in spiderhawk's venom (Pepsis decorata Perty, 1833, Hymenoptera: Pompilidae)

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Oligopeptides analysis in spiderhawk's venom (Pepsis decorata Perty, 1833, Hymenoptera: Pompilidae)

Abstract

Wasps have been neglected in toxinological studies, even with their diversity of species, when compared to other groups of venomous animals such as snakes, scorpions, and spiders. Solitary wasps, such as Pepsis decorata, are known for their mechanism of total or temporary paralysis of the host. In addition, their venoms are considered sources for studies of small peptides, bioactive peptides with neural and antimicrobial activities. In this work, some oligopeptides were analyzed by de novo sequencing identifying 39 oligopeptide sequences. Some sequences were similar to proctolin, a bradykinin-potentiating peptide, and poneritoxin, one bradykinin-related peptide. As proctolin-like peptides were the major constituent in distinct experimental conditions, it was selected for further in silico studies in order to understand its possible importance as a constituent of wasp venom and whether these peptides could be of biotechnological importance. We investigate its binding mode comparing with proctolin and we further analyzed the importance of the tyrosine-leucine-glutamic acid (YLE) tripeptide-motif conservation. This experimental, an in silico approach, increased the range of compounds identified in peptide analyses proving good characterization of little-known peptidic compounds.

Nolasco, M., C. Mariano, D. O., Pimenta, D. C., Pita, R., & Branco, A. Oligopeptides analysis in spiderhawk's venom (Pepsis decorata Perty, 1833, Hymenoptera: Pompilidae). Peptide Science, e24347. https://doi.org/10.1002/pep2.24347