Predation on a Velvet Worm, <i>Epiperipatus</i> sp. (Onycophora: Peripatidae), by a Striped Glasstail,<i> Urotheca guentheri </i>(Squamata: Dipsadidae), in Costa Rica

a small dipsadid (maximum total length ~70 cm) distributed from Honduras to Darin in the Choc Region of Panama (Solrzano 2022).In Costa Rica, it mainly inhabits medium-to high-elevation rainforests along the northern and northeastern Caribbean slope, Caribbean and Pacific sectors of the Cordillera de Tilarn, and the southern and southwestern Pacific slopes of the Cordillera de Talamanca at elevations from sea level to 2,500 m asl (Solrzano 2022).It is active during the day and primarily ground dwelling.Its diet consists primarily of frogs, tadpoles, and possibly small lizards (Savage 2002; Leenders 2019).Abarca et al. ( 2024) recently reported predation on a Pacific Banded Coffee Snake (Ninia maculata) by an adult U. guentheri, broadening its selection of prey to include small snakes.The evidence seems to suggest that, although they feed most frequently on amphibians (especially frogs), species of Urotheca (including Pliocercus euryzonus, which was previously included in this genus) are opportunistic predators (Vriesendorp and Robertson 2007;Durango et al. 2022;Griesbaum et al. 2023; Sosa-Bartuano and Toribio 2023), although their feeding habits in general remain poorly understood.Herein, we report an adult U. guentheri preying on an onychophoran, or velvet worm.At 1122 h on 4 May 2024, we observed an adult Striped Glasstail consuming an unidentified species of velvet worm (Epiperipatus sp., Peripatidae) approximately 8 cm long (Fig. 1) along a tourist trail in rainforest vegetation (Fig. 2) in Mstico Arenal Hanging Bridges Park in La Fortuna, Alajuela Province, on the northwestern Pacific Coast of Costa Rica (10.49012, -85.26061).The onychophoran was still alive and moving when the snake had ingested nearly half of its body, starting with the head.The strategy employed by the snake to avoid the velvet worm's defensive secretions (Monge-Njera and Aguilar 1993) remains unknown.Previous reports of predation on onychophorans include spiders (Franco and Monge-Njera 2016), a single Predation on a Velvet Worm, Epiperipatus sp.