DNA barcoding as an aid for species identification in austral black flies (Insecta: Diptera: Simuliidae)

Abstract

In this paper, the utility of a partial sequence of the COI gene, the DNA barcoding region, for the identification of species of black flies in the austral region was assessed. Twenty-eight morphospecies were analyzed: eight of the genus Austrosimulium (four species in the subgenus Austrosimulium s. str., three species in the subgenus Novaustrosimulium, and one species unassigned to subgenus), two of the genus Cnesia, eight of Gigantodax, three of Paracnephia, one of Paraustrosimulium, and six of Simulium (subgenera Morops, Nevermannia, and Pternaspatha). The neighbour-joining tree derived from the DNA barcode sequences grouped most specimens according to species or species groups recognized by morphotaxonomic studies. Intraspecific sequence divergences within morphologically distinct species ranged from 0% to 1.8%, while higher divergences (2%–4.2%) in certain species suggested the presence of cryptic diversity. The existence of well-defined groups within S. simile revealed the likely inclusion of cryptic diversity. DNA barcodes also showed that specimens identified as C. dissimilis, C. nr. pussilla, and C. ornata might be conspecific, suggesting possible synonymy. DNA barcoding combined with a sound morphotaxonomic framework would provide an effective approach for the identification of black flies in the region.

Society Islands beach bum black flies (Diptera: Simuliidae)

“…While well known (e.g. Crosskey 1990, Craig et al 2012 for simuliid female adults to be found long distances from flowing water, here, final association of immatures and adults will no doubt require further collecting, rearing, and molecular techniques (e.g., Joy & Conn 2001, Hernádez-Triana et al 2017. Based on head proportions, Simulium littosodalis and S. littosocius do not appear to be that closely related; S. littosocius possessing a markedly narrowed frons.…”

DNA barcoding of blackflies (Diptera: Simuliidae) as a tool for species identification and detection of hidden diversity in the eastern regions of Spain

“…We expected higher levels of genetic variation between members of known species complexes, even though cytological studies were not carried out in our study [ 3 , 22 – 24 , 40 ]. With this regard, most of the specimens grouped together, and high levels of genetic diversity was not identified between species complexes.…”

“…The protocols of Hernández-Triana et al [ 3 , 24 ] were used to carry out all molecular work. When pupae were selected for analysis, most of the thorax, gill, and cocoon were retained as a voucher, while the pupal abdomen and/or the thoracic region (ventral side) were used for DNA extraction.…”

“…The family Simuliidae (Diptera) includes 26 genera and 2351 species (2335 extant and 16 fossil) [ 1 ]. The females of many blackfly species bite humans, birds and other animals due to their need of blood for full egg development [ 2 , 3 ]. As a consequence of this hematophagic habit, simuliids can act as intermediate hosts of pathogens affecting the health of humans and animals worldwide [ 4 ].…”

“…Because of their environmental importance together with their impact on public and animal health, the correct identification of this insect group is of a fundamental importance in order to provide correct information on species distribution, biology and behaviour, so that targeted control measures could be correctly applied. However, standard method to blackfly species identification are mainly based on morphology, which typically require expert knowledge and sometimes the resolution can be poor because of the presence of hidden diversity [ 3 , 21 – 24 ]. In this study we developed a molecular platform based on the cox 1 DNA barcoding region in order to support the species identification of the poorly-studied blackfly fauna of Spain.…”