A new species and karyotype variation in the bordering distribution of Mepraia spinolai (Porter) and Mepraia gajardoi Frías et al (Hemiptera: Reduviidae: Triatominae) in chile and its parapatric model of speciation

Abstract

-In the present study, the morphology, color pattern, chromosomal complement and aspects of meiosis in natural populations at the borders of the distributions of Mepraia gajardoi Frías et al and Mepraia spinolai (Porter) are described. The males of these bordering populations are brachypterous or macropterous, while females are always micropterous. Morphological and cytogenetic data indicated that the populations that border the distributions of M. gajardoi and M. spinolai, belong to a different species of parapatric origin. (Sagua et al 2000, Canals et al 2001, Carvajal et al 2007, Botto-Mahan et al 2008. This disease is important in the Neotropical region with nearly 16 million people infected, and another 90 million at risk of contracting the disease, especially in rural areas (Schofi eld et al 1982, Schofi eld 1994.Mepraia gajardoi differs from M. spinolai in body color, morphology, genitalia and karyotype. Females of both species are invariably wingless (micropterous). Males of M. gajardoi are always winged (brachypterous), whereas males of M. spinolai may be winged (macropterous, brachypterous) or wingless (micropterous) (Mazza et al 1940, Neiva & Lent 1940, Lent & Jurberg 1967. Reciprocal crossbreeding experiments showed that the two species are reproductively isolated (Frías et al 1998).The karyotypes of both species are formed by 20 autosomes and an X1 X2 Y sex system. However, males of M. gajardoi have a large Y chromosome, whereas those of M. spinolai are polymorphic for a small neo-Y chromosome, which may have originated by a fracture of the large holocentric Y chromosome of M. gajardoi (Frías & Atria 1998). Also, a particular heteropycnotic chromocenter, typical of M. spinolai, differentiates this species from M. gajardoi. It is formed by sex chromosomes surrounded by several autosomal heteropycnotic dots. Other heteropycnotic regions outside this chromocenter can also be observed (Frías & Atria 1998, Perez et al 2004 In the present study, I report the morphological traits of adults and the chromosomal complement of populations of Mepraia species bordering the distribution of M. gajardoi and M. spinolai, with a discussion of their mode of speciation. Material and MethodsPopulations studied. The specimens examined were collected during the summer of 1996 by D Frías and A Alviña, and during spring, in November 2002, by D Frías, from region III of Atacama and region II of Antofagasta (Fig 1). The former region is located in the Parque Nacional Pan

Description of the diploid chromosome set of Triatoma pintodiasi (Hemiptera, Triatominae)

“…Analysis of early prophase for example, can aid in differentiation between T. sordida and T. guasayana (Rebagliati et al, 1998). Cytogenetic data have also assisted in the revalidation of T. garciabesi (Jurberg et al, 1998); in the description of Mepraia parapatrica (Frías-Lasserre, 2010); and more recently, by analysis of spermatids, in the differentiation of morphologically related species (Alevi et al, 2013b(Alevi et al, , 2014b.…”

Triatominae Survey (Hemiptera: Reduviidae: Triatominae) in the South-Central Region of the State of Bahia, Brazil Between 2008 and 2013

“…Forty-three species are exclusively distributed within Brazil. [5][6][7][8][9][10][11] The state of Bahia in northeastern Brazil has the largest number of species (25 spp.). 8 In Brazil, the National Chagas Disease Control Program (PCDCh) was implemented from 1975 to 1983, when Triatoma infestans infested households in 700 cities across 12 Brazilian states.…”

Climatic factors influencing triatomine occurrence in Central-West Brazil

“…At present, there are 143 known species of triatomines and one fossil specimen has been described (Galvão et al 2003, Costa et al 2006, Costa & Felix 2007, Schofield & Galvão 2009, Frías-Lasserre 2010. In Brazil, 63 species have been documented, but only a few of these are relevant in terms of their synanthropic potential (Silveira et al 1984, Costa et al 2003, Gurgel-Gonçalves et al 2012b.…”