Venom Mass Fingerprints for Species Delimitation, Reloaded: A Test Case with Italian Scorpions (Euscorpius)

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  Venom Mass Fingerprints for Species Delimitation, Reloaded: A Test Case with Italian Scorpions (Euscorpius) Abstract Scorpion venoms are complex mixtures of bioactive compounds including proteins, peptides and enzymes. Although venoms exhibit substantial intraspecific variation, some compounds appear to be species-specific, highlighting their potential as chemotaxonomic markers. Venom mass fingerprints (MFPs) derived from Matrix-Assisted Laser Desorption/Ionization Time-of-Flight (MALDI-TOF) Mass Spectrometry (MS) have been proposed as a means of delimiting species. However, their utility for species delimitation has rarely been evaluated against independent sources of taxonomic evidence. In the present study, the performance of MALDI-TOF MS-based venom peptide barcoding (mass ranges of m/z 800‒4500 and m/z 3000‒10,000) was assessed in 52 populations of eight Italian species of the scorpion genus Euscorpius Thorell, 1876, representing different levels of evolutionary divergenc...

Comparison of lowland tropical forest spider (Araneae) assemblages from Congo and Panama using a rapid assessment protocol

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Comparison of lowland tropical forest spider (Araneae) assemblages from Congo and Panama using a rapid assessment protocol

Abstract

A Rapid Assessment Protocol (RAP) for non-canopy spiders was used to collect replicate samples from four lowland rainforest sites for a proof-of-concept comparison of spider assemblages from the Democratic Republic of the Congo (hereafter, Congo) and Panama. Collecting was done at two 0.25 ha sites in Panama and two 0.25 ha sites in Congo. At each site, three 0.01 ha plots were randomly located, and within each we did 1 person-hour of aerial sampling (sweeping and beating/brushing) and two person-hours of ground sampling (field sieving of leaf litter). The samples yielded 350 adult spiders belonging to 29 spider families. The Panama samples yielded more adult spiders (235 vs. 115) and more spider families (24 vs. 14) than the Congo samples. Overall, the dominant five spider families in these non-canopy samples were Theridiidae (24%), Salticidae (15%), Linyphiidae (11%), Oonopidae (10%), and Pholcidae (7%), with the 20 remaining families each making up less than 5% of the total adults. The three most abundant families in Congo were Theridiidae, Oonopidae, and Thomisidae, while the top three in Panama were Salticidae, Theridiidae, and Linyphiidae. An NMDS ordination analysis of the four plots failed to show significant differences between any of the four assemblages, but when the plots were analyzed by region, there was a significant difference in the family-level assemblages between the continents. This paper shows proof-of-concept that this RAP can produce statistically valid data from brief sampling trips by teams with inexperienced collectors and simple, inexpensive sampling equipment.

Draney ML, Juakaly MJ-L, Sierwald P, Milne MA (2025) Comparison of lowland tropical forest spider (Araneae) assemblages from Congo and Panama using a rapid assessment protocol. African Invertebrates 66(1): 133-150. https://doi.org/10.3897/afrinvertebr.66.138414