Avoid incorporating features or elements that are unrealistic or not consistent with the Temnospondyls amphibian group or the fossil record. While incorporating subtle alien features, ensure they complement the natural attributes of the amphibian rather than overshadowing them. Steer clear of exaggerated or unnatural colors, proportions, or textures that may compromise the overall photorealistic quality of the image. Exclude any modern or contemporary elements that would detract from the authenticity of the prehistoric setting. Strive for accuracy and realism, presenting a visually compelling and believable depiction of a Temnospondyls amphibian with subtle alien features.