Genus Montesauria Oudemans, 1905

Type species: Proctophyllodes (Pterodectes) cylindricus Robin, 1877 by original designation.

The genus Montesauria is the most species-rich genus in the subfamily Pterodectinae and currently includes 54 species arranged in nine species groups (Park & Atyeo 1971a; Mironov & Kopij 1996a, 1996b, 1997; Mironov & Fain 2003; Kuroki et al. 2006; Mironov 2006, 2008, 2009; Hernandes et al. 2010; Mironov et al. 2010). The majority of described species are associated with ten families of passerines, from both the infraorders Passerida and Corvida (Mironov, 2006), with two species recorded from a few non-passeriform hosts, namely from African barbets (Piciformes: Lybiidae) (Gaud & Mouchet 1957) and New Guinean rails (Gruiformes: Rallidae) (Atyeo & Gaud 1977; Hernandes et al. 2010). All representatives of this genus were recorded from birds distributed in the Old World.

The genus Montesauria belongs to the Pterodectes generic group, which unites morphologically derived pterodectine genera, characterized by the posterior or postero-lateral position of setae ps 3 in relation to anal suckers in the male, and associated predominately with passerines (Mironov 2009). Within this generic group, Montesauria and four more genera, Alaudicola Mironov, 1996, Anisodiscus Park and Atyeo, 1971, Dolichodectes Park and Atyeo, 1971, and Pedanodectes Park and Atyeo, 1971, constitute the Montesauria generic complex, representatives of which have the genital papillae situated at the level of the genital arch or posterior to it. This generic complex can be also interpreted as a grouping of derived pterodectines distributed in the Old World.

When Oudemans (1905) established the genus Montesauria he did not clearly differentiate it from Pterodectes Robin, 1877. Therefore until the 1960s, subsequent authors described the species that actually belong to Montesauria as members of the genus Pterodectes, which encompassed in that period all pterodectines in the current sense. Park and Atyeo (1971a) established the subfamily Pterodectinae and gave uniform diagnoses for genera they recognized. As a result of this work the genus Montesauria received a modern diagnosis and became the most numerous genus of the subfamily. Further, Mironov (2006) revised the species content of Montesauria and arranged all known species into nine species groups. Although the species content and taxonomic limits of this genus are relatively clear now, this taxon still needs redescriptions of many species described prior to the 1960s (Trouessart 1885; Robin & Mégnin 1877; Gaud & Petitot 1948; Gaud 1952; Gaud & Mouchet 1957).

Three species of this genus, Montesauria mainati (Trouessart, 1885), M. oxyphylla (Gaud and Petitot, 1948) and M. papillo (Gaud and Petitot, 1948), were previously recorded from Vietnam. In the present paper we describe five new species of the genus Montesauria and establish one new species group in its content. Three previously recorded Montesauria species were not recollected in the course of the present study. Montesauria mainati was recently redescribed based on the type material (Mironov 2006).