A pseudoscorpion clinging to a cave salamander: phoresy or failed predation?

  A pseudoscorpion clinging to a cave salamander: phoresy or failed predation? Abstract Pseudoscorpions are well known for phoretic associations with arthropods, but interactions with amphibians are rarely documented. Here we report a pseudoscorpion attached to the left palpebral region of an adult male Italian cave salamander, Speleomantes italicus , observed during a visual survey in a karst cave in Tuscany, Italy. The pseudoscorpion, assigned on the basis of visible morphology and locality to Chthonius cf. elongatus , was grasping a minute cutaneous fold on the lower margin of the left upper eyelid with one chela while the salamander moved slowly over the rock surface. No handling was performed and the initial contact between the two animals was not observed. The event therefore cannot be interpreted unambiguously, but may represent opportunistic phoresy or defensive attachment following a failed predation attempt. To our knowledge, this is the first published observation of a ...

Interaction of Human Lymphocyte Scavenger Receptors CD5 and CD6 with Toxins from Naja haje, Androctonus australis and Apis mellifera Venoms

 

Image Credit: Luis A. Roque, Arácnido Taxonomy

Interaction of Human Lymphocyte Scavenger Receptors CD5 and CD6 with Toxins from Naja haje, Androctonus australis and Apis mellifera Venoms

Abstract

Animal venoms induce systemic inflammatory response syndrome through their interaction, inter alia, with pattern recognition receptors (PRRs) of the innate immune system. CD5 and CD6 are lymphoid members of the scavenger receptor cysteine-rich superfamily, endowed with PRR activity against microbial-associated molecular patterns (MAMPs) derived from bacteria, fungi, viruses and/or parasites. In this study, we aimed to investigate CD5 and CD6 interaction with cobra (Naja haje), scorpion (Androctonus australis) and honeybee (Apis mellifera) venoms. Binding assays revealed direct, dose-dependent and specific interaction of soluble human CD5 and CD6 receptors with protein nature components from the three venoms. Proteomic analysis identified venom nerve growth factor, basic phospholipase A2 (PLA2) and cobra venom factor, in cobra venom, and scorpion venom toxins targeting potassium (α-KTx 8.1) and sodium channels (Neurotoxin-1″ and G-TI) as potentially interacting components with CD5 and CD6. Further studies confirmed direct binding of bee venom main components, phospholipase A2 and melittin, to both soluble CD5 and CD6 receptors. Interestingly, in vitro PLA2 activity from cobra and bee venom was significantly reduced by both soluble CD5 and CD6 receptors. These findings broaden the PRR properties of CD5 and CD6 and support their potential involvement in envenomation pathophysiology.

Khemili, D., Carrillo-Serradell, L., Planells-Romeo, V., Aragón-Serrano, L., Djilani, S., Hammoudi-Triki, D., Zerouti, K., Mouffok, A., Lozano, F., & Velasco-de-Andrés, M. (2026). Interaction of Human Lymphocyte Scavenger Receptors CD5 and CD6 with Toxins from Naja haje, Androctonus australis and Apis mellifera Venoms. Biomolecules, 16(5). https://doi.org/10.3390/biom16050681