Seasonal Variation in Whole-Body Elemental Concentrations and Excreta Production of a Riparian Orb-Weaving Spider (Larinioides cornutus)

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  Seasonal Variation in Whole-Body Elemental Concentrations and Excreta Production of a Riparian Orb-Weaving Spider (Larinioides cornutus) ABSTRACT Predators influence nutrient cycling by assimilating elements from their prey and returning nutrients to ecosystems via excretion and discarded prey remains. However, seasonal variation in the contribution of predators to nutrient cycling remains poorly understood, particularly for terrestrial arthropod predators such as spiders. We examined temporal variation in whole-body elemental concentrations, excreta C and N concentrations, and cumulative excreta output in a riparian orb-weaving spider ( Larinioides cornutus ) across the growing season of 2024. Adult females were collected across seven sampling periods spanning mid-June to early October, and whole-body concentrations of macronutrients (carbon [C], nitrogen [N], phosphorus [P]) and multiple trace elements were quantified. Whole-body N and P concentrations, and several trace elemen...

Discovery of a new species of Eomysmauchenius from mid-Cretaceous Kachin amber (Araneae: Archaeidae)

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Discovery of a new species of Eomysmauchenius from mid-Cretaceous Kachin amber (Araneae: Archaeidae)

Abstract

Maybe living Archaeidae is only distributed in the southern, but all their fossils have been found in the northern hemisphere. Here, we report a new well-preserved fossil specimen from Kachin amber, which was identified to be a new species of genus Eomysmauchenius Wunderlich, 2008 through a series of morphological characteristics comparison, including a strongly raised cephalic part, a sclerotized ring around the spinnerets and a pedipalpal-cheliceral stridulatory organ absence, cheliceral peg teeth in an irregular position, the distal lateral margin of chelicera with a small triangular projection, length and height almost equal opisthosoma. The discovery of this new species once again increases fossil record diversity of the family Archaeidae in the Cretaceous, and unique palp structure enrich our knowledge of juvenal male pedipalps.

Yuan Peng, Chao Shi, Xiaoxuan Long, Michael S. Engel, Shuo Wang, Discovery of a new species of Eomysmauchenius from mid-Cretaceous Kachin amber (Araneae: Archaeidae), Cretaceous Research, 2023, 105703, ISSN 0195-6671, https://doi.org/10.1016/j.cretres.2023.105703.

(https://www.sciencedirect.com/science/article/pii/S0195667123002318)