Morphometric study of third-instar larvae from five morphotypes of the Anastrepha fraterculus cryptic species complex (Diptera, Tephritidae)

Abstract

The occurrence of cryptic species among economically important fruit flies strongly affects the development of management tactics for these pests. Tools for studying cryptic species not only facilitate evolutionary and systematic studies, but they also provide support for fruit fly management and quarantine activities. Previous studies have shown that the South American fruit fly, Anastrepha fraterculus, is a complex of cryptic species, but few studies have been performed on the morphology of its immature stages. An analysis of mandible shape and linear morphometric variability was applied to third-instar larvae of five morphotypes of the Anastrepha fraterculus complex: Mexican, Andean, Ecuadorian, Peruvian and Brazilian-1. Outline geometric morphometry was used to study the mouth hook shape and linear morphometry analysis was performed using 24 linear measurements of the body, cephalopharyngeal skeleton, mouth hook and hypopharyngeal sclerite. Different morphotypes were grouped accurately using canonical discriminant analyses of both the geometric and linear morphometry. The shape of the mandible differed among the morphotypes, and the anterior spiracle length, number of tubules of the anterior spiracle, length and height of the mouth hook and length of the cephalopharyngeal skeleton were the most significant variables in the linear morphometric analysis. Third-instar larvae provide useful characters for studies of cryptic species in the Anastrepha fraterculus complex.

Incipient speciation in theAnastrepha fraterculuscryptic species complex: reproductive compatibility betweenA. sp.1 aff.fraterculusandA. sp.3 aff.fraterculus

“…The analysis of pre‐ and post‐zygotic isolation among populations of cryptic species is of considerable interest, mainly when this theoretical knowledge has practical relevance. The Anastrepha fraterculus Wiedemann (Diptera: Tephritidae) cryptic species complex comprises different biological strains under the same species designation though they differ in terms of genetic, morphological, and morphometric characteristics (Stone, ; Steck, ; Selivon & Perondini, ; Smith‐Caldas et al., ; Hernández‐Ortiz et al., , ; Selivon et al., , ; Barr et al., ; Silva & Barr, ; Cáceres et al., ; Canal et al., ; Dias et al., ). This economically important complex (Zucchi, ) is distributed from northern Mexico to the south of South America (Stone, ; Aluja, ; Malavasi et al., ; Norrbom, ).…”

Development and validation of a simplified morphological identification key for larvae of tephritid species most commonly intercepted at import in Europe

“…However, it was not possible to include them in the key due a lack of reference material to work on. In the case of Anastrepha spp., it was very difficult to reach a diagnostic at the specific level since the number of tubules is very variable (Canal et al, 2015). However, the specific form of anterior spiracles and absence of the dental sclerite combined with information on the distribution (in the New World) are enough to allow identification at the generic level.…”

Preliminary assessment of cephalopharyngeal skeleton length and body length of Hemipyrellia ligurriens (Wiedemann) (Diptera: Calliphoridae) larvae as potential parameters to estimate minimum post mortem interval

“…Allometric growth patterns in dipterous larvae have been recorded in few developmental studies by highlighting the measurements of cephalopharyngeal skeleton segments, but they were not extended to forensic application (Lawrence 1979;Petitt 1990). Other than being useful in species identification and distinguishing cryptic species (Canal et al 2015), cephalopharyngeal skeleton of dipterous larvae has been used to describe the growth patterns (Rabbani and Zuha 2017;Simon et al 2011), but the information is still scarce. It is possible, from the present findings, allometric growth of forensically important larvae could be explored further on its patterns and developmental model.…”