New records of Rileya hegeli Girault, 1916 (Hymenoptera, Eurytomidae) from Brazil

. Rileya hegeli Girault, 1916 (Hymenoptera, Eurytomidae) was previously known in USA, Mexico, Guatemala, Costa Rica, Dominican Republic, Jamaica, Venezuela and, in Brazil, in the states of Minas Gerais and Rio Grande do Sul. Here, we newly report this species from the Brazilian municipalities of Alto Paraíso de Goiás, in Goiás state, Brazil, obtained through collections with Malaise traps, of Ribeirão Preto and Águas de São Pedro, in São Paulo state, reared from leaf galls of Eugeniamyia dispar Maia, Mendonça & Romanowski, 1996 (Diptera, Cecidomyiidae) on Eugenia uniflora L. (Myrtaceae) and of Palhoça, in Santa Catarina state, reared from galls of an unidentified Cecidomyiidae gall-maker in fruits of E. uniflora . Additionally, we provide a map with the geographical distribution of the studied species based on the new records and literature.

Rileya Ashmead, 1888 (Hymenoptera, Eurytomidae, Rileyinae) comprises currently 65 species from Holarctic, Australasian and Neotropical regions; the genus is most speciose in the Neotropics, primarily in Central and South Americas where it includes 57 species, 13 of them with recorded occurrence for Brazil (Gates 2008;Noyes 2019;Perioto et al. 2020).
Eugeniamyia dispar is reported as one of the limiting factors to the cultivation of E. uniflora trees, mainly in plant nurseries, where abiotic factors such as rain and temperature and biotics such as parasitism and predation occur in lower intensity than in natural conditions (Salles 1995;Bierhals et al. 2012). Each female of Eu. dispar can lay up to 30 eggs placed, preferably, close to the petiole and the main vein of new leaves of E. uniflora; after emergence, its larvae penetrate the leaf tissue, which induces the formation of galls (Maia et al. 1996;Mendonça & Romanowski 2002;Bianchia et al. 2018) resulting from hypertrophy of plant tissues triggered by a single galling larva (Mendonça & Romanowski 2002). At the end of the late larval stage, larvae of Eu. dispar leave the galls to pupate in the soil, from which the adults emerge (Bierhals et al. 2012).
Females of R. hegeli (Fig. 2) insert the ovipositor into the galls and lay an egg on the last instar larvae of Eu. dispar. After hatching, R. hegeli larvae settle on the host and feed on it and, at the end of the larval cycle, pupate inside the gall. To emerge, the adults open a small hole in the gall wall with their mandibles through which they exit into the external environment (N.W. Perioto personal communication).

Scientific Note
In the Brazilian territory, E. uniflora occurs in various physiographic formations such as Caatinga, Brazilian savanna and Atlantic rainforest (Bourscheid et al. 2011) and is widely cultivated in domestic backyards (Lorenzi et al. 2006). In Brazil, the commercial cultivation of this fruit tree, both for in natura consumption and for the industrial preparation of sweets, jams, ice cream, juices, etc has been carried out mainly in the states of Pernambuco, Bahia and Rio Grande do Sul (Silva 2006; A lavoura 2016). Our knowledge about the geographical distribution of R. hegeli is far from complete. Rileya hegeli has been described by A. A. Girault based on one female collected by W. H. Ashmead from Biscaine Bay, Florida, USA (Girault 1916) and has wide geographic distribution, with occurrence records for the USA (Texas, Florida), Mexico, Guatemala, Costa Rica, Dominican Republic, Jamaica, Venezuela and, in Brazil, in the states of Minas Gerais and Rio Grande do Sul (Gates 2008;Noyes 2019).
There are no formal records of the occurrence of R. hegeli in the Brazilian states of Goiás, São Paulo and Santa Catarina. Thus, we present the first records of R. hegeli for those states based on specimens collected with Malaise trap in a Brazilian savanna vegetation area in Alto Paraíso de Goiás (Goiás state), on specimens reared from galls produced by Eu. dispar in leaves of E. uniflora collected in Ribeirão Preto and Águas de São Pedro (São Paulo state), and specimens reared from an unidentified species of Cecidomyiidae that causes galls in fruits of E. uniflora collected in Palhoça (Santa Catarina state) (Fig. 3).
Rileya hegeli was identified using the key provided by Gates (2008).
Observations were carried out using a Leica S APO stereomicroscope with 10X oculars under led light source.
Digital images of a young plant of E. uniflora with galls produced by Eu. dispar were taken using the camera of a mobile phone Motorola Moto G 50.
Digital images of R. hegeli were taken using a Leica MC170 HD digital camera coupled to a Leica M205C APO stereomicroscope. The specimen was illuminated with a Leica LED5000 HDI high diffuse dome illumination. The digital images were combined using Helicon Focus (version 8.1.0) software to obtain a single image in extended focus. The figures were prepared using Adobe Photoshop (version 11.0) software.
The provided map with the geographical distribution of R. hegeli was generated with the Simplemappr tool (Shorthouse 2010) and is based on data from literature and new records.
Abbreviation used: Gtn (n= number of tergum) = gastral terga. The information on the labels of the examined specimens has been transcribed in the examined material section as follows: the backslash symbol ( \ ) indicates the different lines on the label and two quotation marks ( " " ) indicate different labels on the same specimen.
These new records extend the geographic range of R. hegeli to Alto Paraíso de Goiás, in the state of Goiás, to Ribeirão Preto and Águas de São Pedro, in the state of São Paulo and to Palhoça, in the state of Santa Catarina, about 5,600, 6,200 and 6,800 km southeast of the type locality, respectively (Fig. 3). Considering that E. uniflora occurs in various physiographic formations such as Caatinga, Brazilian savanna and Atlantic rainforest (Bourscheid et al. 2011) and is a widely cultivated plant in Brazil (Lorenzi et al. 2006), it is expected that R. hegeli is distributed throughout much of the Brazilian territory.