A new species ofPristimantisis described from an Andean cloud forest at 2650 m in the Cordillera Oriental of Colombia.Pristimantis doradosp. nov. is similar to and could be closely related toP. acutirostris, but can be readily distinguished from this latter species by the absence of a tympanic annulus, vocal slits, vocal sac and reticulations on concealed surfaces, and by having a metallic gold iris with a brown horizontal streak. The phylogenetic position of the new species is recovered and we provide its advertisement call, which this species manages to emit despite lacking a vocal sac and vocal slits. This discovery reminds us that despite the extensive research on the alpha-taxonomy ofPristimantisin Colombia, fieldwork in high montane forests continues to yield previously unknown species.

Glucocorticoid (GC) release is triggered by adverse stimuli that activate the hypothalamus-pituitary-adrenal/interrenal axis. Glucocorticoids may enhance or suppress immune functions depending on the level of elevation. In this study, we investigated the effects of transient and chronic increase of corticosterone (CORT) on the wound healing of the American bullfrog. Frogs were submitted to a daily transdermal hormonal application that acutely elevated CORT plasma levels, or vehicle as a control. Other frogs were surgically implanted with a silastic tube filled with CORT that resulted in chronic elevation of CORT plasma levels or received empty implants as a control. A dermal biopsy was performed to create a wound and was photographed every 3 days. Individuals treated with transdermal CORT started healing faster than their control 32 days after the biopsy. Frogs that received CORT implants tended to heal slower than control subjects. Plasma bacterial killing ability was not affected by treatment, which reinforces the constitutive nature of this innate immune trait. By the end of the experiment, frogs from the acute CORT treatment had smaller wounds compared with those receiving the CORT-filled implants, highlighting the differential effects of acute (immunoenhancing) and chronic (immunosuppressive) elevation of CORT plasma levels. This article is part of the theme issue ‘Amphibian immunity: stress, disease and ecoimmunology’.

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A resistência aos antibióticos é um grave problema de saúde pública. Adicionalmente, o uso de antibióticos para tratamento de pacientes com COVID-19 aumentou a incidência de bactérias multirresistentes (MDR), agravando o problema de escassez global de antibióticos. Neste cenário, fontes não convencionais como os anfíbios têm surgido como uma nova fonte de peptídeos e probióticos. Sendo que a pele é a primeira linha de defesa contra patógenos, os peptídeos antimicrobianos (PAMs) presentes nas secreções cutâneas e bactérias cutâneas produtoras de metabólitos (BPMs) fornecem compostos com potencial atividade antimicrobiana. Esta revisão apresenta o potencial dos PAMs e dos BPMs contra bactérias patogênicas de interesse clínico, assim como sua atividade sinérgica em combinação com os antibióticos comercialmente disponíveis. Evidências elucidaram que os PAMs apresentam atividade antimicrobiana contra isolados clínicos, porém são limitados na sua aplicação farmacológica devido à toxicidade. Por outro lado, os BPMs têm se mostrado promissores na inibição de patógenos, entretanto seu espectro de ação é reduzido. O estudo de anfíbios demonstra ser promissor na busca de novos antibióticos, assim como também para potencializar o efeito terapêutico dos antibióticos disponíveis. Estes fatos são relevantes no Brasil, o país com maior diversidade de anfíbios no mundo.