We present notable distributional updates for 14 species from western Ecuador (seven amphibians and seven reptiles). Our findings include the northernmost confirmed sighting of Pristimantis kuri (Yánez-Muñoz et al. 2016) and the southernmost documented record of Imantodes inornatus (Boulenger 1896) and Lepidoblepharis buchwaldi (Werner 1910). Additionally, we document new records and notes on the distribution range of Agalychnis spurrelli (Boulenger 1913), Hyloscirtus alytolylax (Duellman 1972), Engystomops montubio (Ron et al. 2004), Pristimantis muricatus (Lynch and Miyata 1980), Pristimantis nyctophylax (Lynch 1976), Pristimantis walkeri (Lynch 1974), Chironius flavopictus (Werner 1909), Chironius grandisquamis (Peters 1869), Dendrophidion graciliverpa (Cadle 2012), Ninia schmidti (Arteaga and Harris 2023), and Urotheca fulviceps (Cope 1886). These observations significantly contribute to filling information gaps in our understanding of these species' distributions. The data, derived from samples collected across diverse forested areas in the western region of Ecuador (provinces of Bolívar, Cañar, Guayas, El Oro, and Los Ríos), provide valuable insights into the ecology and conservation of these species.

The data was collected during scientific exploratory expeditions in ten tropical forests in western Ecuador, from January 2014 to December 2023, utilizing non-systematic sampling, a search that was both free and unrestricted, visual recordings, and manual capture methods (Rödel and Ernst 2004). According to the Ministerio del Ambiente del Ecuador (2013), four of the ten forests sampled presented a seasonal foothill evergreen forest of the western Cordillera de Los Andes; these sites were: 1) The Cerro de Hayas Provincial Natural Recreation Area (camp point: 2° 43' 50.9'' S, 79° 37' 43'' W, alt. 120 m), in the foothills of the Molleturo-Mollepungo mountain range, Naranjal canton, Guayas province, Ecuador. Cerro de Hayas is a private reserve that protects 631 ha of forests in mountainous landscapes with streams and waterfalls. 2) Rancho Alemán (Camp point: 2° 20' 13.6'' S, 79° 12' 46.8'' W, alt. 235 m), in the western foothills of the Cordillera de Los Andes, El Triunfo canton, Guayas province, Ecuador. Rancho Alemán is an ecotourism farm that has 25 ha of forest in mountainous landscapes with streams and surrounded by the Blanco River. 3) San Pablo town (Camp point: 2° 20' 55'' S, 79° 10' 28.9'' W, alt. 431 m), in the western foothills of the Cordillera de Los Andes, Cañar canton, Cañar province, Ecuador. A small town surrounded by mountains, ravines, and small waterfalls, where there are patches of forests and areas dedicated to agriculture. 4) Cascadas de Manuel (Camping point: 3° 12' 23.1'' S, 79° 44' 9.8'' W, alt. 182 m) located in the El Guabo canton, El Oro province. It has mature forest extension, that occupies almost the entire micro-basin with a dense tree cover, with an interior vegetation based on herbaceous and shrubs. Three forests are evergreen foothill forest of the western Cordillera de Los Andes, which were: 5) The surroundings of the El Progreso farm (Camping point: 2° 7' 39.4'' S, 79° 7' 17'' W, alt. 944 m) in the western foothills of the Cordillera de Los Andes, Chillanes canton, Bolivar province, Ecuador. This site is a tourist farm that presents forest patches with mountainous landscapes with streams, ravines, waterfalls and crop areas. 6) El bosque del Amigo farm (Camping point: 2° 17' 3.5 '' S, 79° 6' 23'' W, alt. 879 m), in the western foothills of the Cordillera de Los Andes, Cañar canton, Cañar province, Ecuador. This site is an ecotourism farm that has 300 ha, has large tracts of forest with mountains, a large number of small streams and small areas for agriculture. 7) The surroundings of the Ocaña (Camping point: 2° 29' 3.7'' S, 79° 15' 12.2'' W, alt. 946 m), in the western foothills of the Cordillera de Los Andes, Cañar canton, Cañar province, Ecuador. There were large patches of forest on sloping slopes of the Río Cañar. The forests were dense with predominantly shrubby vegetation and herbaceous in its interior.

Other ecosystems were, evergreen seasonal lowland forest of Jama-Zapotillo that was 8) Pedro Franco Dávila Protected Forest (Camp point: 1° 14' 44.2'' S, 79° 39' 36'' W, alt. 50 m), in the central region of the Ecuadorian coast, Palenque canton, Los Ríos province, Ecuador. This site has 140 ha of protected forest, a tropical humid forest with two climatic seasons : rainy season (January-May) and dry season (June-December). In addition, it presents mainland forest, rivers, streams and small swampy areas. 9) The surroundings of Mocache (Camping point: 1° 9' 40.9'' S, 79° 30' 29.4'' W, alt. 57 m), Vinces canton, Los Ríos province, Ecuador. It is located on the banks of the Vinces River, has small fragments of intervened forest. Its vegetation is sparse, it has few shrubs and abundant leaf litter. 10) The surroundings of Macul (Camping point: 1° 36' 22.1'' S, 79° 50' 58.8'' W, alt. 18 m), Vinces canton, Los Ríos province, Ecuador. Located next to the river, it has small remnants of intervened forest rich in litter, but with very little shrub and herbaceous vegetation.

Specimens were hand-captured, photographed, and euthanized using 2% roxicaine anesthetic solution, fixed in 10% formalin, and preserved in 70% ethanol. Before fixation, tissue samples were taken from the collected individuals and preserved in 96% ethanol, following the method described by Székely et al. (2016). The specimens are deposited in the following museums: Museo de Zoología de la Universidad Técnica Particular de Loja (MUTPL), Loja, Ecuador; Museo de Zoología de la Universidad del Azuay (MZUA), Cuenca, Ecuador; Museo de Zoología de la Pontificia Universidad Católica del Ecuador (QCAZ), Quito, Ecuador; and Museo de Zoología, Universidad San Francisco de Quito (ZSFQ), Quito, Ecuador. Snout-vent length (SVL) measurements were taken with digital calipers and rounded to the nearest 0.1 mm for small specimens, and with a tape measure for longer specimens. The coordinates and elevation were taken with a Garmin GPSMAP 62st GPS equipment. Specimens were collected under permit No. MAE-DPALR-UPN-UB-2015-002, 008-2015-IC-FLO/FAU-DPG/MAE, MAAE-DBI-DBI-CM-2022-0222, MAAE-ARSFC-2022-2204 and No. MAATE-ARSFC-2023-0063 approved by the Ministerio del Ambiente, Agua y Transición Ecológica.