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

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  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 ...

Morphology and Genetic Diversity of Golden Silk Orb-weaver (Nephila) Spiders in Thailand

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Morphology and Genetic Diversity of Golden Silk Orb-weaver (Nephila) Spiders in Thailand

Spiders play a pivotal role in ecosystems, serving as predators to regulate populations of small organisms. They commonly exhibit body color polymorphism which could be due to a combination of environmental factors, adaptation, or genetic drift from population subdivision. This polymorphism, in turn, could affect their behavior and prey capture efficiency. Certain morphological traits may be unique to specific subregions, suggesting possible subspecies classification. In this study, we examined morphological polymorphism in the giant wood spider, Nephila pilipes, in Thailand, particularly focusing on leg variation and genetic variation at the cytochrome c oxidase I (COI) gene. We used partial sequence of the COI gene for our samples and constructed a phylogenetic tree by including other species. We explored the relationship between morphological polymorphism, COI genotype, and geographic distribution. Our findings categorized female N. pilipes into seven types based on legs I and IV, with no correlation to geographic region. The N. pilipes specimens formed two clades, each containing all leg types and collection regions, consistent with low genetic differentiation within the species. Trichonephila antipodiana specimens formed three clades while all Argyrodes flavescens specimens were grouped into a monophyletic clade. Additionally, Nephila kuhli, previously suggested to be a melanic morph of N. pilipes, was also included in the N. pilipes cluster, with a low genetic distance. Our results suggest that the leg variants in N. pilipes represent polymorphism within the species rather than distinct biospecies.

Lertkulvanich F, Swatdipong A, Warrit N, Nipitwattanaphon M. 2025. Morphology and genetic diversity of golden silk orb-weaver (Nephila) spiders in Thailand. Zool Stud 64:53. doi:10.6620/ZS.2025.64-53. ( Received 14 May 2025 / Accepted 11 August 2025 / Published 06 November 2025 ) DOI: https://doi.org/10.6620/ZS.2025.64-53