Ecological and geographical speciation in Lucilia bufonivora: The evolution of amphibian obligate parasitism

Gerardo Arias Robledo, Richard L Wall, Krzysztof Szpila, Danny Shpeley, Terry Whitworth, Tariq Stark, Andrew King, Jamie Stevens

Research output: Contribution to journalArticle (Academic Journal)

2 Citations (Scopus)
109 Downloads (Pure)

Abstract

Lucilia (Diptera: Calliphoridae) is a genus of blowflies comprised largely of saprophagous and facultative parasites of livestock. Lucilia bufonivora, however, exhibits a unique form of obligate parasitism of amphibians, typically affecting wild hosts. The evolutionary route by which amphibian myiasis arose, however, is not well understood due to the low phylogenetic resolution in existing nuclear DNA phylogenies. Furthermore, the timing of when specificity for amphibian hosts arose in L. bufonivora is also unknown. In addition, this species was recently reported for the first time in North America (Canada) and, to date, no molecular studies have analysed the evolutionary relationships between individuals from Eastern and Western hemispheres. To provide broader insights into the evolution of the amphibian parasitic life history trait and to estimate when the trait first arose, a time-scaled phylogeny was inferred from a concatenated data set comprising mtDNA, nDNA and non-coding rDNA (COX1, per and ITS2 respectively). Specimens from Canada, the UK, Poland, Switzerland, the Netherlands and Germany were analysed, as well as individuals from its sister taxa, the saprophage Lucilia silvarum and a Nearctic species also implicated in amphibian myiasis, Lucilia elongata. Obligate amphibian parasitism appears to have arisen ~4 mya, likely as a result of niche displacement of a saprophagous/facultative parasite ancestor. Consistent paraphyly of L. bufonivora with respect to L. elongata across single-gene phylogenies and high mtDNA genetic distances between Nearctic and Palearctic individuals suggest on-going cryptic speciation facilitated by geographical isolation. These findings suggest that recent reports of L. bufonivora in the Nearctic do not constitute a recent introduction, but instead suggest that it remained unrecorded due to taxonomic confusion and low abundance. This is the first study to confirm the involvement of L. bufonivora in amphibian myiasis in Canada using DNA-based identification methods.

Original languageEnglish
Pages (from-to)218-230
Number of pages13
JournalInternational Journal for Parasitology: Parasites and Wildlife
Volume10
Early online date22 Sep 2019
DOIs
Publication statusPublished - 1 Dec 2019

Keywords

  • Amphibian parasitism
  • Blowfly
  • Host specialisation
  • Lucilia
  • Myiasis
  • Obligate parasitism

Fingerprint Dive into the research topics of 'Ecological and geographical speciation in <i>Lucilia bufonivora</i>: The evolution of amphibian obligate parasitism'. Together they form a unique fingerprint.

  • Student Theses

    Lucilia blowflies: their ecology, taxonomy and the evolution of obligate amphibian parasitism

    Author: Arias Robledo, G., 1 Oct 2019

    Supervisor: Morgan, E. (Supervisor) & Wall, R. (Supervisor)

    Student thesis: Doctoral ThesisDoctor of Philosophy (PhD)

    File

    Cite this