TY - JOUR

T1 - ‘Barcode fishing’ for archival DNA from historical type material overcomes taxonomic hurdles, enabling the description of a new frog species

AU - Scherz, Mark D.

AU - Rasolonjatovo, Safidy M.

AU - Köhler, Jörn

AU - Rancilhac, Loïs

AU - Rakotoarison, Andolalao

AU - Raselimanana, Achille P.

AU - Ohler, Annemarie

AU - Preick, Michaela

AU - Hofreiter, Michael

AU - Glaw, Frank

AU - Vences, Miguel

N1 - Funding Information: We would like to thank all of the many colleagues and guides who have joined us in the field over innumerable visits to different parts of Madagascar. We thank B. Stuart and two anonymous reviewers for their constructive feedback on this paper. We thank the Malagasy authorities in the Forestry Department and Madagascar National Parks for providing us with permits and access to protected areas to conduct fieldwork and export samples. The 2017–2018 expedition to Montagne d’Ambre (permit number N°191/17-MEEF/SG/DGF/DSAP/SCB.Re) was funded by a Deutsche Forschungsgemeinschaft grant (VE 247/13-1) to MV and MDS. The archival DNA analysis was supported by a Deutsche Forschungsgemeinschaft grant (VE247/16-1 – HO 3492/6-1) to MH, LR and MV, in the framework of the Taxon-Omics priority program (SPP 1991). The 2007 survey of northern Madagascar was financially supported by the European Association of Zoos and Aquaria (EAZA). SMR was funded by grants from the National Geographic Society (WW-121ER-17). Association Vahatra was funded by Leona M. & Harry B. Helmsley Charitable Trust under the program ‘Development of scientist capacity for Malagasy conservation biologists’ and scholarships granted by Jai Shekhawat. We acknowledge support by the German Research Foundation and the Open Access Publication Funds of the Technische Universität Braunschweig. Publisher Copyright: © 2020, The Author(s).

PY - 2020

Y1 - 2020

N2 - Taxonomic progress is often hindered by intrinsic factors, such as morphologically cryptic species that require a broad suite of methods to distinguish, and extrinsic factors, such as uncertainties in the allocation of scientific names to species. These uncertainties can be due to a wide variety of factors, including old and poorly preserved type specimens (which contain only heavily degraded DNA or have lost important diagnostic characters), inappropriately chosen type specimens (e.g. juveniles without diagnostic characters) or poorly documented type specimens (with unprecise, incorrect, or missing locality data). Thanks to modern sequencing technologies it is now possible to overcome many such extrinsic factors by sequencing DNA from name-bearing type specimens of uncertain assignment and assigning these to known genetic lineages. Here, we apply this approach to frogs of the Mantidactylus ambreensis complex, which was recently shown to consist of two genetic lineages supported by concordant differentiation in mitochondrial and nuclear genes. These lineages co-occur on the Montagne dʼAmbre Massif in northern Madagascar but appear to have diverged in allopatry. We use a recently published bait set based on three mitochondrial markers from all known Malagasy frog lineages to capture DNA sequences from the 127-year-old holotype of Mantidactylus ambreensis Mocquard, 1895. With the obtained sequences we are able to assign the name M. ambreensis to the lowland lineage, which is rather widespread in the rainforests of northern Madagascar, leaving the microendemic high-elevation lineage on Montagne d’Ambre in north Madagascar in need of description. We describe this species as Mantidactylus ambony sp. nov., differing from M. ambreensis in call parameters and a smaller body size. Thus, using target enrichment to obtain DNA sequence data from this old specimen, we were able to resolve the extrinsic (nomenclatural) hindrances to taxonomic resolution of this complex. We discuss the broad-scale versatility of this ‘barcode fishing’ approach, which can draw on the enormous success of global DNA barcoding initiatives to quickly and efficiently assign type specimens to lineages.

AB - Taxonomic progress is often hindered by intrinsic factors, such as morphologically cryptic species that require a broad suite of methods to distinguish, and extrinsic factors, such as uncertainties in the allocation of scientific names to species. These uncertainties can be due to a wide variety of factors, including old and poorly preserved type specimens (which contain only heavily degraded DNA or have lost important diagnostic characters), inappropriately chosen type specimens (e.g. juveniles without diagnostic characters) or poorly documented type specimens (with unprecise, incorrect, or missing locality data). Thanks to modern sequencing technologies it is now possible to overcome many such extrinsic factors by sequencing DNA from name-bearing type specimens of uncertain assignment and assigning these to known genetic lineages. Here, we apply this approach to frogs of the Mantidactylus ambreensis complex, which was recently shown to consist of two genetic lineages supported by concordant differentiation in mitochondrial and nuclear genes. These lineages co-occur on the Montagne dʼAmbre Massif in northern Madagascar but appear to have diverged in allopatry. We use a recently published bait set based on three mitochondrial markers from all known Malagasy frog lineages to capture DNA sequences from the 127-year-old holotype of Mantidactylus ambreensis Mocquard, 1895. With the obtained sequences we are able to assign the name M. ambreensis to the lowland lineage, which is rather widespread in the rainforests of northern Madagascar, leaving the microendemic high-elevation lineage on Montagne d’Ambre in north Madagascar in need of description. We describe this species as Mantidactylus ambony sp. nov., differing from M. ambreensis in call parameters and a smaller body size. Thus, using target enrichment to obtain DNA sequence data from this old specimen, we were able to resolve the extrinsic (nomenclatural) hindrances to taxonomic resolution of this complex. We discuss the broad-scale versatility of this ‘barcode fishing’ approach, which can draw on the enormous success of global DNA barcoding initiatives to quickly and efficiently assign type specimens to lineages.

U2 - 10.1038/s41598-020-75431-9

DO - 10.1038/s41598-020-75431-9

M3 - Journal article

C2 - 33154397

AN - SCOPUS:85095112498

VL - 10

JO - Scientific Reports

JF - Scientific Reports

SN - 2045-2322

M1 - 19109

ER -