ABSTRACT We studied several ecological aspects of the endemic Ololygon kautskyi in the Reserva Biológica Duas Bocas (RBDB), Espírito Santo, Brazil, including activity, detectability and use of microhabitats. Fieldwork was carried out from February 2018 to March 2019, between 8:00 and 23:00, in 22 transects of 50 m along streams. For each individual frog found, we recorded the hour, the microhabitat in which it was detected, the height above ground, snout-vent length (in mm), and mass (in g). We measured the air temperature (°C), relative humidity (%), stream water temperature (°C), pH, and conductivity. We tested for differences in body size among sexes and estimated the detectability of the species in relation to the environmental variables. We recorded a total of 93 individuals from O. kautskyi, with the majority of individuals recorded between 18:00 and 22:00. Females were significantly larger in body size than males. The detection probability of the species was affected by the period of the day, air temperature and relative air humidity. Ololygon kautskyi used five different types of microhabitats, and vegetation was the most used microhabitat by the species. We conclude that O. kautskyi is nocturnal, mainly uses vegetation on stream banks, is more likely to be detected during cold and dry days, and is dimorphic in body size with females being larger than males. There is currently insufficient information to assess the conservation status of O. kautskyi. However, considering that the species is endemic to a relatively small portion of the Atlantic Forest biome in the state of Espírito Santo and that its ecology is strongly associated with riparian zones, we believe that the species would be eligible to be categorised in some threat category.

中文翻译：

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巴西东南部大西洋森林地区特有树蛙 Ololygon kautskyi（Anura：Hylidae）的生态方面

摘要我们研究了巴西圣埃斯皮里图博卡斯生物保护区 (RBDB) 中地方性 Ololygon kautskyi 的几个生态方面，包括活动、可检​​测性和微生境的使用。实地调查于 2018 年 2 月至 2019 年 3 月，在 8:00 至 23:00 之间，在沿溪流 50 m 的 22 条断面中进行。对于发现的每只青蛙，我们记录了时间、检测到它的微栖息地、离地高度、口鼻部长度（以毫米为单位）和质量（以克为单位）。我们测量了空气温度 (°C)、相对湿度 (%)、溪流水温 (°C)、pH 值和电导率。我们测试了两性之间体型的差异，并估计了与环境变量相关的物种的可检测性。我们总共记录了 93 个人来自 O. kautskyi，大多数人在 18:00 到 22:00 之间记录。女性的体型明显大于男性。该物种的检测概率受白天时段、气温和空气相对湿度的影响。Ololygon kautskyi 使用了五种不同类型的微生境，植被是该物种使用最多的微生境。我们得出结论，O. kautskyi 是夜间活动的，主要利用河岸上的植被，在寒冷和干燥的日子里更容易被发现，并且体型二态，雌性比雄性大。目前没有足够的信息来评估 O. kautskyi 的保护状况。然而，