Molecular phylogenetics of Oestroidea (Diptera: Calyptratae) with emphasis on Calliphoridae: Insights into the inter-familial relationships and additional evidence for paraphyly among blowflies

Abstract

The superfamily Oestroidea, comprising ∼15,000 species, is a large and ecologically diverse clade within the order Diptera. Among its six commonly recognized families, Calliphoridae seems to be crucial for understanding evolutionary relationships in the group, as it is recognized as a controversial paraphyletic grouping. To further investigate this matter, the ITS2, 28S, COI and 16S regions were used to infer phylogenetic relationships in Oestroidea with maximum-parsimony (MP), maximum-likelihood (ML) and Bayesian inference (BI) methods. For the BI analyses, a deep evaluation of different data partitioning strategies was conducted, including consideration of structural conformation (ITS2 and 16S) and codon position (COI) information. Results suggest the existence of two main clades in Oestroidea: (Tachinidae+Mesembrinellinae) and (Rhiniinae, (Sarcophagidae+Calliphoridae sensu stricto)). Oestridae was recovered as sister group of the remaining Oestroidea in the MP trees while it was placed closer to the (Rhiniinae+Sarcophagidae+Calliphoridae sensu stricto) group in the ML and BI trees. A paraphyletic Calliphoridae was recovered, confirming the exclusion of Rhiniinae, a clade recently promoted to family status and therefore already excluded. Mesembrinellinae could also be considered a distinct group apart from Calliphoridae, although further studies are required. Consideration of structural and codon position information led to a significant increase in the log-likelihoods of the analyses, which were accompanied by small changes in the inferred topologies, branch lengths and posterior probability support values. However, as model complexity increases, so does uncertainty across the estimated parameters, including tree topologies, and phylogenies inferred under very parameter-rich models may be less reliable even when possessing higher log-likelihoods.

Molecular Systematics of the Calliphoridae (Diptera: Oestroidea): Evidence From One Mitochondrial and Three Nuclear Genes

“…We conÞrmed the earlier conclusion of oestroid monophyly (Pape 1992, Rognes 1997, Kutty et al 2008, Kutty et al 2010. Our well-supported Calliphoridae (excluding Mesembrinellinae) ϩ Rhinophoridae ϩ Tachinidae is in agreement with Wiegmann et al (2011) but at odds with the hypotheses that Sarcophagidae is the sister group of Tachinidae (Pape 1992, Rognes 1997, Tachi and Shima 2010 or Calliphoridae (Marinho et al 2012) and also suggests to us that Rhinophoridae is either closely related to Calliphoridae (Tschorsnig 1985;Rognes 1986Rognes , 1991Kutty et al 2008) or Tachinidae (Wood 1987, McAlpine 1989 and not to Sarcophagidae (Rohdendorf 1967). Morphologically, Rhinophoridae looks intermediate between typical calliphorids and typical tachinids (Pape 1986).…”

“…These results add to a growing body of work supporting rhinophorid monophyly (Pape 1992, Pape and Arnaud 2001, Kutty et al 2010. They are in conßict with the Rhiniinae ϩ (Sarcophagidae ϩ Tachinidae) (Rognes 1997) or Rhiniinae ϩ (Sarcophagidae ϩ Calliphoridae) (Marinho et al 2012) and we believe that they undermine the case for elevating Rhiniinae to family rank (Evenhuis et al 2008, Kutty et al 2010, Marinho et al 2012) (see next section).…”

“…Monophyly of Calliphorinae ϩ Toxotarsinae was also advocated by Greenberg and Szyska (1984) based on larval morphology and developmental rate and by based on molecular data (COI and CAD genes). Same was true in recent molecular systematic analysis by Marinho et al (2012).…”

“…Relationships between oestroid families were mostly unresolved as was the case in previous molecular studies (Kutty et al 2010, Wiegmann et al 2011, Marinho et al 2012. It may be that these groups evolved recently in a very short span of time and hence lack enough character accumulation for any phylogenetic resolution (Wiegmann et al 2011).…”

“…The latter hypothesis inspired recent authors to raise its rank from subfamily to family (Evenhuis et al 2008). Recent molecular systematic analysis also supported a family level upgrade of Rhiniinae as a sister group of Calliphoridae ϩ Tachinidae ϩ Oestridae ϩ Rhinophoridae (Kutty et al 2010) or Calliphoridae ϩ Sarcophagidae (Marinho et al 2012).…”