Trichophoromyia ruifreitasi sp. n. is described as a new species of sand fly from the genus Trichophoromyia Barretto. This description is supported with illustrations and photographs that detail the morphological characteristics of male specimens collected in the municipality of Assis Brasil, Acre State, Brazilian Amazon. This species is similar to T. auraensis (Mangabeira), but the two species can be easily differentiated by the distribution of setae on their parameres, and by the presence of a dorsal lobe in the parameres of the new species.

Sand fly, taxonomy, Neotropical region, leishmaniasis, Psychodidae , Phlebotominae

Phlebotomine sand flies are small, dipteran, hematophagous insects. They are vectors of etiological agents such as Leishmania Ross, a protozoan that causes leishmaniases (Young and Duncan 1994). These diseases occur throughout the world, and infection can result in mutilations and death. Sand fly diversity is higher in the Amazon basin than it is in other biomes (Barret et al. 1996, Alves et al. 2012).

The genus Trichophoromyia Barretto is of medical importance because some species are involved in the life cycle of Leishmania (Viannia) lainsoni Silveira, Shaw, Braga and Ishikawa, and L. (V.) braziliensis Vianna (Silveira et al. 1991, Martinez et al. 2001, Valdivia et al. 2012, Pereira Junior et al. 2015). To date, 41 species have been described of this diverse genus (Ladeia-Andrade et al. 2014, Fernandez et al. 2015). Most descriptions are based on male specimens, because the females of this genus are morphologically similar in most cases.

A study of phlebotomine sand fly diversity was undertaken in the region where Brazil borders Peru and Bolivia. A list of collected species was previously presented in Teles et al. (2013). These authors reported that T. auraensis (Mangabeira) is a known vector in that area (Valdivia et al. 2012; Araújo-Pereira et al. 2014). After reexamining the sand flies collected and identified as T. auraensis, it was discovered that the specimens belonged to a similar, but distinct species. The present paper describes this new species based on male specimens.

Forest fragments were sampled in the municipality of Assis Brasil, located approximately 330 km south west of Rio Branco, Acre, Brazil, on the east bank of the Acre river, bordering Bolivia and Peru. Sand flies were captured between November 2009 and October 2010, using CDC light traps placed approximately 100 meters from domestic habitats. Details of the collection methods can be found in Teles et al. (2013). Insects were individually slide-mounted in synthetic Canada balsam. Specimens were identified and measured using a Zeiss microscope calibrated with a micrometer scale, and specimens were drawn using a camera lucida. All measurements are in micrometers (µm); measurements of the holotype are followed in parentheses by the measurement range of the paratypes, and the number of specimens observed. Morphological characteristics are also illustrated by photomicrographs that were made using a Leica DM 1000 optical microscope coupled to a JVC - 3 CCD digital camera and a computer imaging system.

Nomenclature and morphological terminology is according to Galati (2003).

Trichophoromyia ruifreitasi sp. n. and two other species of its genus share the same type locality. These species have distinct parameres: T. auraensis has a paramere (Figs 2f and 3b) that is completely covered with long setae, lacks a dorsal lobe, and is digitiform in the apical half. T. ruifreitasi has a subtriangular paramere with a discrete dorsal lobe, and approximately 30 long, recurved setae. T. melloi (Causey and Damasceno) has a paramere with a very pronounced dorsal lobe in the tip, with setae present solely within the apical region.

Two new Trichophoromyia species have recently been described in the Amazon basin: T. nautaensis in Loreto State, Peru, described by Fernandez, Lopez, Roldan and Requena; and, T. adelsonsouzai in Pará State, described by Santos, Silva, Barata, Andrade and Galati. Both species have parameres with dorsal lobes; however, in T. nautaensis the lobe is located in the median part of the paramere, while in T. adelsonsouzai the paramere has a relatively broad hump, exhibiting dorsal curvature in the apical region (Fernandez et al. 2015; Santos et al. 2014).

In comparison with other known species from the genus Trichophoromyia, the parameres of the new species, T. napoensis and T. sp.1 of Araracuara are similar. The digital area after the dorsal proximal lobe is approximately twice as long as it is broad in the new species compared with the other two species. However, T. napoensis is distinct from the others in that it possesses 2-3 long recurved setae at paramere apex, and a tuft of setae concentrated at the tip of dorsal lobe (Young and Duncan 1994). The parameres of T. ruifreitasi and T. sp.1 of Araracuara are covered by setae. Trichophoromyia sp.1 of Araracuara species possesses 4-6 long setae near its lateral ventral margin of the paramere apex (Young and Duncan 1994). Additionally, T. sp.1 of Araracuara also possesses other setae that are smaller than the width of the dorsal lobe, while T. ruifreitasi possess long setae that are distributed in the dorsal lobe. Santos et al. (2014) recently gave a brief review of the genus Trichophoromyia, and described T. adelsonsouzai, differentiating between the majority of species in the genus, except by the T. napoensis and T. sp.1 of Araracuara, not included in their analysis, and more closely related with the paramere of T. ruifreitasi. The new species described here raises the number of Trichophoromyia species worldwide to 42, and 21 in Brazil.

To our technical illustrator Mr. Artêmio Coelho da Silva, and FAPESP for financial support (PROCESS Nr. 2008/11319-0). To Dr Sergio Bernal, Dr Gunnar Kvifte and an anonymous reviewer for their constructive comments.