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Abstract BackgroundOur current understanding of vertebrate skin and gut microbiomes, and their vertical transmission, remains incomplete as major lineages and varied forms of parental care remain unexplored. The diverse and elaborate forms of parental care exhibited by amphibians constitute an ideal system to study microbe transmission, yet investigations of vertical transmission among frogs and salamanders have been inconclusive. In this study, we assess bacteria transmission inHerpele squalostoma,an oviparous direct-developing caecilian in which females obligately attend juveniles that feed on their mother’s skin (dermatophagy). ResultsWe used 16S rRNA amplicon-sequencing of the skin and gut of wild caughtH. squalostomaindividuals (males, females, including those attending juveniles) as well as environmental samples. Sourcetracker analyses revealed that juveniles obtain an important portion of their skin and gut bacteria communities from their mother. The contribution of a mother’s skin to the skin and gut of her respective juveniles was much larger than that of any other bacteria source. In contrast to males and females not attending juveniles, only the skins of juveniles and their mothers were colonized by bacteria taxa Verrucomicrobiaceae, Nocardioidaceae, and Erysipelotrichaceae. In addition to providing indirect evidence for microbiome transmission linked to parental care among amphibians, our study also points to noticeable differences between the skin and gut communities ofH. squalostomaand that of many frogs and salamanders, which warrants further investigation. ConclusionOur study is the first to find strong support for vertical bacteria transmission attributed to parental care in a direct-developing amphibian species. This suggests that obligate parental care may promote microbiome transmission in caecilians.
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An effective way to mark cohorts of juvenile terrestrial direct-developing frogs
Abstract. Marking juveniles of terrestrial direct-developing frogs is challenging because of their small size (< 18 mm) and fragility. This difficulty has limited studies on demography or population dynamics where empirical data on the survivorship of juveniles or their recruitment to adulthood are missing. In a controlled laboratory experiment, we tested the survivorship of wild-caught juvenile Eleutherodactylus coqui Thomas, 1966 to marking with a single colour visual internal elastomer (VIE) in the thigh, with and without additional ventral skin-swabbing for disease or microbiome monitoring. Results revealed 100% survival in all groups, and all juveniles remained unharmed, moved freely, and fed actively during three days after treatment, suggesting that this type of manipulation does not cause direct mortality. After 17 months of the experiment, we have recaptured 11% of the marked juveniles as adults, indicating that they can survive to recruitment age. We propose the use of a single VIE colour as a method to mark and follow date-specific cohorts of juvenile direct-developing frogs or young metamorphs until they reach older and larger age classes. This marking method can be used safely together with skin swabbing and provide valuable information for studies on population biology and age-specific response to environmental or disease stressors.
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- Award ID(s):
- 2011281
- PAR ID:
- 10342227
- Editor(s):
- Kaiser, Hinrich; Zagar, Anamarija; Müller, Hendrik
- Date Published:
- Journal Name:
- Herpetology notes
- Volume:
- 14
- Issue:
- 2021
- ISSN:
- 2071-5773
- Page Range / eLocation ID:
- 1037 - 1042
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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