A.G. Abreu, V.N. Solferini
Published: November 02, 2008
Genet. Mol. Res. 7 (4) : 1298-1311
DOI: https://doi.org/10.4238/vol7-4gmr534

Cite this Article:
A.G. Abreu, V.N. Solferini (2008). Genetic population structure and hybridization in two sibling species, Tomoplagia reticulata and Tomoplagia pallens (Diptera: Tephritidae). Genet. Mol. Res. 7(4): 1298-1311. https://doi.org/10.4238/vol7-4gmr534

About the Authors
A.G. Abreu, V.N. Solferini

Corresponding author
A.G. Abreu
E-mail: agabreu@gmail.com

ABSTRACT

Tomoplagia reticulata and T. pallens are sibling species that are specialists on Eremanthus glomerulatus. Besides adult terminalia, they show slight morphological differences and distinct geographic distributions. Once, however, they were found sympatrically. Using data from allozyme and mtDNA, we examined patterns of intra- and interspecific genetic structure, and investigated the possible occurrence of gene flow between them. Both species showed low diversity and high genetic structure, which can be linked to their high degree of specialization. Larval development occurs within flower heads, tissues that are available only during a short period of the year. Afterward, as they do not hibernate, they probably suffer a great reduction in population size, which leads to low genetic diversity. As monophagous insects, their population structure may correspond to the fragmented distribution of E. glomerulatus, which could isolate fly populations and increase inbreeding within them. One population exhibited a mixed genetic composition, compatible with one hybridization season when species were sympatric. This hybridization seems to be a rare event, due to T. pallens unusual range expansion.

Key words: Allozymes, Asteraceae, Cerrado, mtDNA, Campo rupestre, Eremanthus glomerulatus.