Diversity and antibiotic resistance profiles of bacteria isolated from the oral cavity of captive snakes

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  Diversity and antibiotic resistance profiles of bacteria isolated from the oral cavity of captive snakes Abstract Venomous snake bites are a global public health issue, causing between 81 000 and 138 000 annual deaths and 400 000 permanent disabilities. This study investigated the oral bacterial diversity and antibiotic resistance profiles in captive  Viperidae  snakes. Oral swabs from 48 specimens across four species ( Porthidium lansbergii ,  Bothriechis nigroviridis ,  Cerrophidion sasai , and  Bothrops asper ) were analyzed using culture-dependent methods. Bacterial isolation and identification using the VITEK 2 automated system revealed 41 strains from 12 genera, predominantly Gram-negative bacteria, including  Morganella morganii  (11 isolates) and  Providencia rettgeri  (10 isolates). Antibiotic susceptibility testing demonstrated significant resistance patterns, with 100% resistance to cephalothin and cefazolin i...

Effect of web inclination on debris-induced damage in Leucauge venusta webs (Araneae: Tetragnathidae)

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By Kaldari - Own work, Public Domain, https://commons.wikimedia.org/w/index.php?curid=7585412

Effect of web inclination on debris-induced damage in Leucauge venusta webs (Araneae: Tetragnathidae)

Abstract

Spiders are among the most conspicuous trap builders in nature, and the structure and orientation of spider webs are presumably under strong selection pressure. Most ecribellate orb-weavers (Araneoidea) build vertically-orientated webs (0°; ie the plane of the web is orthogonal to the ground). However, Leucauge venusta (Tetragnathidae; Walckenaer, 1842) often build horizontally-orientated webs (90°; ie parallel to the ground), despite evidence that prey capture and retention rates are higher in vertical webs. Falling debris is a common hazard for webs in the forest understory, and basic geometry predicts that vertical webs sustain more damage when struck by a falling object. Here, we quantified the angle of web inclination in L. venusta and its effect on the amount of damage sustained from falling debris. We experimentally damaged L. venusta webs in the laboratory and measured natural damage to webs in the field. As predicted, webs inclined 30° or 45° relative to vertical in the laboratory sustained more damage than horizontal (90°) webs; by contrast, the proportional damage observed in the field was not related to web inclination (which ranged 21° to 90°). Thus, under controlled laboratory conditions, the horizontal orientation of L. venusta webs minimizes damage from debris fall. However, falling objects are just one of many potential sources of web damage in nature, and the relevance of web size and location to the frequency and magnitude of damage remains unclear. The results improve our understanding of the role of web orientation in the balance between prey capture and local environmental challenges.

Fortner, S. A., Nienaber, A. K., Stark, A. Y., & Yanoviak, S. P. (2026). Effect of web inclination on debris-induced damage in Leucauge venusta webs (Araneae: Tetragnathidae). Environmental Entomology, 55(2). https://doi.org/10.1093/ee/nvag031