Molecular and Phenotypic Data Support the Recognition of the Wakatobi Flowerpecker (Dicaeum kuehni) from the Unique and Understudied Sulawesi Region

Abstract

Accurate estimates of species richness are essential to macroecological and macroevolutionary research, as well as to the effective management and conservation of biodiversity. The resolution of taxonomic relationships is therefore of vital importance. While molecular methods have revolutionised taxonomy, contemporary species delimitation requires an integrative, multi-disciplinary approach. Despite boasting a remarkably high level of endemism, the avifauna of the Sulawesi region of Indonesia remains poorly studied. Previous studies of avian diversity in Sulawesi have focussed predominantly on phenotypic characteristics, thus potentially overlooking any genetically distinct lineages. Grey-sided Flowerpecker Dicaeum celebicum populations from the Wakatobi archipelago were originally described as a separate species from those on nearby mainland Sulawesi. However, for reasons that remain unknown, the Wakatobi populations were reclassified as a subspecies of the mainland form. Combining estimates of genetic divergence with phylogenetic and morphological analyses, we reassessed the status of Wakatobi populations. Our results describe the Wakatobi populations as a separate species to those on mainland Sulawesi; reproductively isolated, genetically and morphologically distinct. We therefore recommend the reclassification of these populations to their original status of Dicaeum kuehni and propose the vernacular name ‘Wakatobi Flowerpecker’. In consideration of our findings and the lack of integrative ornithological research within the Sulawesi region, we believe species richness and avian endemism within the region are underestimated.

Diversification of a ‘great speciator’ in the Wallacea region: differing responses of closely related resident and migratory kingfisher species (Aves: Alcedinidae: Todiramphus)

“…Juvenile Sacred Kingfishers were distinguished by 'feathers of forehead and secondary coverts of upperwing fringed buff' (Coates & Bishop 1997, Higgins 1999. The polymerase chain reaction (PCR) procedure was adapted from Kelly et al (2014). The morphological measurements of wing (maximum chord), bill, and skull lengths and mass (Redfern & Clark 2001) were taken.…”

“…DNA was extracted from feathers using a Qiagen DNeasy Blood and Tissue Kit (Qiagen, California, USA), following Kelly et al (2014). We sequenced three mitochondrial genes: the entire second and third subunits of mitochondrial nicotinamide adenine dinucleotide dehydrogenase (ND2 and ND3, respectively) and a 626-bp region of the cytochrome c oxidase subunit 1 (COI) gene.…”

“…Several novel primers were developed for use with ND2 and ND3 (Table S2), primarily to facilitate the sequencing of ND2 in two halves. The polymerase chain reaction (PCR) procedure was adapted from Kelly et al (2014). All PCR amplifications were performed in 20-lL reactions, consisting of 8.1 lL double-distilled H 2 O, 0.4 lL 10 mM deoxynucleoside triphosphates (dNTPs), 2 lL 109 PCR buffer, 2.4 lL 25 mM MgCl 2 , 1 lL 10 lM forward primer, 1 lL 10 lM reverse primer, 0.1 lL Taq polymerase (New England Biolabs) and 5 lL template DNA.…”

“…1). Although the Wakatobi Islands are only separated from Buton by 27 km, they are home to five unique bird subspecies (Kelly & Marples 2010) and a proposed new species of flowerpecker (Kelly et al 2014). Although the Wakatobi Islands are only separated from Buton by 27 km, they are home to five unique bird subspecies (Kelly & Marples 2010) and a proposed new species of flowerpecker (Kelly et al 2014).…”

“…It includes continental islands (Buton, Muna and Kabaena), which were connected to Sulawesi at the time of the last glacial maximum, around 10 000 years ago (Voris 2000), and also oceanic islands (the Wakatobi Islands), which have never been connected to the Sulawesi mainland (Carstensen et al 2012). Although the Wakatobi Islands are only separated from Buton by 27 km, they are home to five unique bird subspecies (Kelly & Marples 2010) and a proposed new species of flowerpecker (Kelly et al 2014). However, the Wakatobi's kingfisher populations have not been investigated since early taxonomic assessments of the region (Hartert 1903).…”