Monty Wood

Wolbachia and DNA barcoding insects: Patterns, potential, and problems

Wolbachia is a genus of bacterial endosymbionts that impacts the breeding systems of their hosts. Wolbachia can confuse the patterns of mitochondrial variation, including DNA barcodes, because it influences the pathways through which mitochondria are inherited. We examined the extent to which these endosymbionts are detected in routine DNA barcoding, assessed their impact upon the insect sequence divergence and identification accuracy, and considered the variation present in Wolbachia COI. Using both standard PCR assays (Wolbachia surface coding protein – wsp), and bacterial COI fragments we found evidence of Wolbachia in insect total genomic extracts created for DNA barcoding library construction. When >2 million insect COI trace files were examined on the Barcode of Life Datasystem (BOLD) Wolbachia COI was present in 0.16% of the cases. It is possible to generate Wolbachia COI using standard insect primers; however, that amplicon was never confused with the COI of the host. Wolbachia alleles recovered were predominantly Supergroup A and were broadly distributed geographically and phylogenetically. We conclude that the presence of the Wolbachia DNA in total genomic extracts made from insects is unlikely to compromise the accuracy of the DNA barcode library; in fact, the ability to query this DNA library (the database and the extracts) for endosymbionts is one of the ancillary benefits of such a large scale endeavor – for which we provide several examples. It is our conclusion that regular assays for Wolbachia presence and type can, and should, be adopted by large scale insect barcoding initiatives. While COI is one of the five multi-locus sequence typing (MLST) genes used for categorizing Wolbachia, there is limited overlap with the eukaryotic DNA barcode region.

Host utilization by Exorista thula Wood (sp. nov.) and Chetogena gelida (Coquillett) (Diptera: Tachinidae), parasitoids of arctic Gynaephora species (Lepidoptera: Lymantriidae)

Abstract. Studies of host-parasitoid interactions undertaken at Alexandra Fiord, Ellesmere Island, Canada, during the summers of 1994, 1995, and 1996 revealed only two species of tachinid flies parasitic on arctic Gynaephora species. Exorista thula sp. nov. (described herein by D.M. Wood) is from the North American Arctic and is parasitic on Gynaephora groenlandica. Remarks on the systematics of Exorista subgenus Exorista in North America and an identification key for arctic and subarctic species of the tribe Exoristini are included. Chetogena gelida, parasitic on Gynaephora rossii, and E. thula were found to be extremely host specific. Both species of parasitoids developed predominantly on final-instar larvae of their respective hosts, but E. thula also emerged from the penultimate instar (9% of E. thula adults, 19% of hosts) and occasionally from the pupal stage (4% of E. thula adults, 3% of hosts) of G. groenlandica.

Figure 44 In Revision Of The New World Species Of Houghia Coquillett (Diptera, Tachinidae) Reared From Caterpillars In Area De Conservación Guanacaste, Costa Rica

FIGURE 44. General morphology of Houghia triangularis sp. nov. a. Dorsal habitus. b. Frontal view of head. c. Lateral habitus. d. Posterior view of male terminalia. e. Lateral view of male terminalia. f. Ventral view of sternite 5 + segments 7 + 8.

Figure 42 In Revision Of The New World Species Of Houghia Coquillett (Diptera, Tachinidae) Reared From Caterpillars In Area De Conservación Guanacaste, Costa Rica

FIGURE 42. General morphology of Houghia sexmaculata sp. nov. a. Dorsal habitus. b. Frontal view of head. c. Lateral habitus. d. Posterior view of male terminalia. e. Lateral view of male terminalia.

Figure 38 In Revision Of The New World Species Of Houghia Coquillett (Diptera, Tachinidae) Reared From Caterpillars In Area De Conservación Guanacaste, Costa Rica

FIGURE 38. General morphology of Houghia pallida sp. nov. a. Dorsal habitus. b. Frontal view of head. c. Lateral habitus. d. Posterior view of male terminalia. e. Lateral view of male terminalia. f. Ventral view of sternite 5 + segments 7 + 8.

Figure 36 In Revision Of The New World Species Of Houghia Coquillett (Diptera, Tachinidae) Reared From Caterpillars In Area De Conservación Guanacaste, Costa Rica

FIGURE 36. General morphology of Houghia ochrofemur sp. nov. a. Dorsal habitus. b. Frontal view of head. c. Lateral habitus. d. Posterior view of male terminalia. e. Lateral view of male terminalia. f. Ventral view of sternite 5 + segments 7 + 8.

Figure 34 In Revision Of The New World Species Of Houghia Coquillett (Diptera, Tachinidae) Reared From Caterpillars In Area De Conservación Guanacaste, Costa Rica

FIGURE 34. General morphology of Houghia matarritai sp. nov. a. Dorsal habitus. b. Frontal view of head. c. Lateral habitus. d. Posterior view of male terminalia. e. Lateral view of male terminalia. f. Ventral view of sternite 5 + segments 7 + 8.

Figure 27 In Revision Of The New World Species Of Houghia Coquillett (Diptera, Tachinidae) Reared From Caterpillars In Area De Conservación Guanacaste, Costa Rica

FIGURE 27. General morphology of Houghia latigena sp. nov. a. Dorsal habitus. b. Frontal view of head. c. Lateral habitus. d. Posterior view of male terminalia. e. Lateral view of male terminalia. f. Ventral view of sternite 5 + segments 7 + 8.

Figure 23 In Revision Of The New World Species Of Houghia Coquillett (Diptera, Tachinidae) Reared From Caterpillars In Area De Conservación Guanacaste, Costa Rica

FIGURE 23. General morphology of Houghia gracilis sp. nov. a. Dorsal habitus. b. Frontal view of head. c. Lateral habitus. d. Posterior view of male terminalia. e. Lateral view of male terminalia. f. Ventral view of sternite 5 + segments 7 + 8.

Figure 22 In Revision Of The New World Species Of Houghia Coquillett (Diptera, Tachinidae) Reared From Caterpillars In Area De Conservación Guanacaste, Costa Rica

FIGURE 22. General morphology of Houghia fimbriata sp. nov. a. Dorsal habitus. b. Frontal view of head. c. Lateral habitus. d. Posterior view of male terminalia. e. Lateral view of male terminalia. f. Ventral view of sternite 5 + segments 7 + 8.