Many anuran species are characterized by sexually dimorphic skin glands. These glands often are concentrated on specific areas, such as the mental region, flanks, or the nuptial pads. We studied the histology and histochemistry of mental and lateral glands in Hypsiboas punctatus, and compared them to skin from other body regions. We describe four types of dermal glands, two types of mucous and two types of serous glands. The mucous glands are formed by a single layered epithelium. The mucocytes surrounding a central lumen are filled with polyhedral granules. Ordinary mucous glands are small sized glands with cubical epithelium, mucoid content, and small granules. Specialized mucous glands are characterized by a larger size, a columnar epithelium, a proteinaceous content and larger granules. Both types of serous glands are syncytial and share some structural features including size, shape, and morphology of secretory granules. However, ordinary and specialized serous glands differ in their histochemical properties, size and appearance of secretory granules, and glandular outlets. The specialized type of mucous glands in H. punctatus resembles most SDSGs described in anurans, whereas the presence of specialized serous glands that are sexually dimorphic is less common. Both specialized glands occur only in mental and lateral regions of males, whereas ordinary mucous and ordinary serous glands occur in males and females.

Avoiding predation is critical to survival of animals; chemical defenses represent a common strategy among amphibians. In this study, we examined histologically the morphology of skin glands and types of secretions related to chemical skin defense during ontogeny of Rhinella arenarum. Prior to metamorphic climax the epidermis contains typical bufonid giant cells producing a mucous substance supposedly involved in triggering a flight reaction of the tadpole school. An apical layer of alcianophilic mucus covers the epidermis, which could produce the unpleasant taste of bufonid tadpoles. Giant cells disappear by onset of metamorphic climax, when multicellular glands start developing, but the apical mucous layer remains. By the end of climax, neither the granular glands of the dorsum nor the parotoid regions are completely developed. Conversely, by the end of metamorphosis the mucous glands are partially developed and secrete mucus. Adults have at least three types of granular glands, which we designate type A (acidophilic), type B (basophilic) and ventral (mucous). Polymorphic granular glands distribute differently in the body: dorsal granular glands between warts and in the periphery of parotoids contain protein; granular glands of big warts and in the central region of parotoids contain catecholamines, lipids, and glycoconjugates, whereas ventral granular glands produce acidic glycoconjugates. Mucous glands produce both mucus and proteins. Results suggest that in early juveniles the chemical skin defense mechanisms are not functional. Topographical differences in adult skin secretions suggest that granular glands from the big warts in the skin produce similar toxins to the parotoid glands. Anat Rec, 299:141-156, 2016. V C 2015 Wiley Periodicals, Inc.

Aesculus hippocastanum L. seed extract shows virucidal and antiviral activities against respiratory syncytial virus (RSV) and reduces lung inflammation in vivo

We describe the structure and histochemistry of mental and lateral glands in a representative array of 28 species of five genera of the Neotropical hylid frog tribe Cophomantini. Structural diversity was coded in 15 characters that were optimized on the most recent phylogenetic hypothesis. Mental and lateral glands occur in 17 species and 10 species, respectively, whereas nine species have both. Each glandular concentration may have two types of sexually dimorphic skin glands (SDSGs), specialized mucous and specialized serous glands, which occur independently or may co‐occur. Distinctive characteristics related to these glands are shape, aspect of the secretion, disposition, and distribution. The occurrences of mental and lateral glands, and the characters derived from macroscopic and microscopic examinations, have an intricate taxonomic distribution, with differing levels of homoplasy. The function of SDSGs in Cophomantini is currently unknown. However, based on structural and histochemical similarities to SDSGs from other species of amphibians where experimental evidence exists, we infer they might be involved in the secretion of chemical signals during courtship behaviour. The distribution pattern of these glands, along with the existence of different signals (i.e. acoustic, visual, tactile), suggests the presence of multimodal signalling for some species of the tribe. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 114, 12–34.

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The ultrastructure of mature spermatozoa is investigated for the Wrst time in the Volutidae, based on the commercially signiWcant South American species Zidona dufresnei (Donovan, 1823) (fresh material) and supplemented with observations on testicular (museum) material of the deep sea New Zealand species Provocator mirabilis (Finlay, 1926). Euspermatozoa of Z. dufresnei (ex sperm duct) consist of: (1) a tall-conical acrosomal vesicle (with short basal invagination, constricted anteriorly) which is Xattened anteriorly and associated with an axial rod, centrally perforate basal plate and short accessory membrane;(2) a rod-shaped, solid and highly electron-dense nucleus (with short basal fossa containing centriolar complex and initial portion of a 9 + 2 axoneme); (3) an elongate midpiece consisting of the axoneme sheathed by 5-6 helical mitochondrial elements, each exhibiting a dense U-shaped outer layer; (4) an elongate glycogen piece (axoneme sheathed by nine tracts of putative glycogen granules); (5) a dense annulus at the junction of the midpiece and glycogen piece and (6) a short free tail region (axoneme surrounded only by plasma membrane). Paraspermatozoa of Z. dufresnei are vermiform and dimorphic: the Wrst type contains approximately 14-20 axonemes (arranged peripherally and interspersed with microtubules) and numerous oblong dense vesicles, numerous less dense (round) vesicles, occasional, large lipid-like vesicles, and scattered mitochondria; the second type contains 25-31 axonemes (peripherally arranged, interspersed with microtubules), occasional mitochondria and extensive cytoplasm. Results obtained for P. mirabilis from testis material are essentially as observed in Z. dufresnei, although the euspermatozoan acrosome still has to achieve its compressed transverse proWle. Observations on paraspermatozoa were limited by Wxation quality of available (testis) tissues, but these cells are similar to the Wrst type of Zidona paraspermatozoa. Although most of the euspermatozoal features are also observed in many neotaenioglossans and neogastropods, the U-shaped outer layer of each mitochondrial element has not previously been reported and may prove a diagnostic feature of the Volutidae, the subfamily Zidoniinae or possibly only the Zidonini (in which Z. dufresnei and P. mirabilis are currently placed).

Ferraro, D.P., Topa, P.E. and Hermida, G.N. 2011. Lumbar glands in the frog genera Pleurodema and Somuncuria (Anura: Leiuperidae): histological and histochemical perspectives. —Acta Zoologica (Stockholm) 00: 1–14. Abstract The skin in the lumbar region of nine species of Pleurodema and in the monotypic genus Somuncuria (Anura: Leiuperidae) bears macroglands [lumbar gland (LG)]. Lumbar glands of Pleurodema bibroni, P. borellii, P. brachyops, P. bufoninum, P. cinereum, P. cordobae, P. kriegi, and P. thaul, as well as Somuncuria somuncurensis, were examined using histological and histochemical methods. The epidermis and the dermis of LGs are described. Also, skin of LGs presents characteristic features as the interruption of the Eberth–Katschenko layer and the presence of a differentiated type of gland only observed in macrogland and not previously described for Pleurodema or Somuncuria; this is termed lumbar serous gland. These glands are filled with a granular product, which occasionally is immersed in a matrix. Differences in the secretory products of mucous and serous glands are described, as well as inter‐ and intraspecific variability of gland structure. The mode of toxin expulsion from macroglands and the homology between lumbar and inguinal glands among anuran families are discussed.

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