de Toledo R C, Jared C
Rev Bras Biol. 1989 May;49(2):421-8.
Frogs of the Pleurodema thaul species have a pair of prominent elevated cutaneous glands dorsolaterally, just posterior to the sacrum, which are named lumbar glands. We have studied histologically these glands and found that their chromatophores are disposed mainly immediately under the epidermis structuring a dermal chromatophore unit. Similar to the other anuran macroglands, the lumbar glands are constituted basically by granular alveoli filled with secretion. The presence of these granular alveoli and the typical distribution of the dermal chromatophores to suggest a defensive role for the lumbar glands. In most of the amphibians granular alveoli contain secretions with toxicity for several vertebrates. On the other hand, chromatophores in this frog species, probably play an aposematic function, since their disposition on the skin permits that the lumbar glands might be taken for eyes, probably giving to an eventual predator the impression that it may be an animal of higher dimensions.
图勒侧褶蛙（Pleurodema thaul）物种的青蛙在背外侧、骶骨后方有一对突出的隆起皮肤腺，称为腰腺。我们对这些腺体进行了组织学研究，发现它们的色素细胞主要分布在紧挨着表皮的下方，构成一个真皮色素细胞单位。与其他无尾目大腺体相似，腰腺基本上由充满分泌物的颗粒状腺泡组成。这些颗粒状腺泡的存在以及真皮色素细胞的典型分布表明腰腺具有防御作用。在大多数两栖动物中，颗粒状腺泡含有对几种脊椎动物有毒的分泌物。另一方面，这种青蛙物种的色素细胞可能起到警戒功能，因为它们在皮肤上的分布使得腰腺可能被误认为是眼睛，这可能会给潜在的捕食者一种它是体型更大动物的印象。
