First records of Periscelididae ( Diptera , Opomyzoidea ) from French Guiana

Periscelididae (Diptera, Opomyzoidea) are recorded for the first time from French Guiana, with 5 species Marbenia peculiaris Malloch, 1931, Neoscutops barcelosiensis Ale-Rocha & Freitas, 2011, Neoscutops flavoscutellatus AleRocha & Freitas, 2011, Neoscutops peruvianus Hennig, 1969, and Planinasus nigritarsus Mathis & Rung, 2012 found.


Introduction
Periscelididae are a small cosmopolitan family that is more diverse in the Neotropical Region.Representatives of Periscelididae are associated with sap exuding from deciduous trees (Periscelidinae) or with phytotelmata in the axils of monocotyledons (Stenomicrinae) (Mathis and Rung 2011).Information about the immature stages is very scarce and largely from temperate regions (Williams 1939, Teskey 1976, Papp 1988, 1995, 1998).In the Neotropical Region, information on the biological cycle of Stenomicra species associated with Eryngium L. (Apiaceae) in Argentina was provided by Campos et al. (2010).Additionally, Gomes et al. (2018) described a Stenomicra species from material reared in the axils of Alocasia macrorrhizos (L.) G.Don (Araceae) at an urban forest fragment in Brazil.
Here we adopt D.K. McAlpine's (1978McAlpine's ( , 1983) concept of Periscelididae, which includes Cyamops Melander, 1913, Planinasus Cresson, 1914, and Stenomicra Coquillett, 1900, previously allocated to Aulacigastridae.We also adopt the division of the family in 2 subfamilies, Periscelidinae and Stenomicrinae (Grimaldi and Mathis 1993, Baptista and Mathis 1994, Mathis and Papp 1998).Periscelididae flies have broad to slender bodies, body length of 2.5-5 mm, convex and setose face with ventral portion retreated, 1-2 fronto-orbital setae, pedicel caplike with a dorsal cleft, arista bipectinate, postocellar setae divergent or absent,1 or 2 dorsocentral postsutural setae,vein C lacking true breaks and extended to vein R 4+5 or vein M, cell dm with a shallow longitudinal fold, vein CuA 2 well developed or not completely closing cell cup, and mid tibia with 1 apicoventral spine-like seta.Mathis and Rung (2011) compiled a global catalog of the Periscelididae.In the Neotropical Region, Ale-Rocha and Freitas (2011), Mathis et al. (2012) and Ale-Rocha et al. (2014) revised the Neotropical genera Neoscutops Malloch, 1926, Planinasus Cresson, 1913, and Marbenia Malloch, 1931, respectively.In this contribution we document the first records of Periscelididae for French Guiana.We provide a list of Periscelididae species and their known distribution based on the literature, new records and material examined.We also provide maps with the geographic distribution of each species.

Methods
The material examined belongs to the Natural History Museum (NHMUK), London, United Kingdom.In total 7 specimens were studied.The identification of the mate-  Specimens were photographed with a Leica MC170 HD camera, attached on a Leica M165 C stereomicroscope.Later, photographs were stacked and combined using Leica Application Suite V4.11.Distribution maps were created with Simplemappr (Shorthouse 2010), using coordinates present on the specimen labels and bibliography.
Morphological terminology for adult structures follows those of Cumming and Wood (2009).

Marbenia Malloch, 1931
Diagnosis.Representatives of this genus are character-  ized as follows: small flies, body length 2.6-3.5 mm; maxillary palpus short and spatulate; setae of head elongate; postocellar pair well developed; only a pair of setae on facial plate, face with transverse grooves providing a wavy appearance; parafacial, gena, and occiput with numerous strong developed setae; 2 pairs of dorsocentral setae; wing banded; R 1 with dorsal setae; R 2+3 long and arcuate; M almost straight; bm-cu complete; CuA 2 lacking; A 1 +CuA 2 extended close to wing margin.

Planinasus Cresson, 1914
Diagnosis.Planinasus can be distinguished from other genera of Periscelididae as follows: frons with a pair of interfrontal setae, 2 fronto-orbital setae, ocellar setae and postocellar setae absent, basal flagellomere arising from anterior surface of pedicel, costal vein extended to vein M, vein CuA 2 present, cell cup distinct, forefemur with 1-3 posteroventral setae on apical half, scutellum bearing only 1 pair of marginal setae, these apical, tibiae with a dorsoapical seta (Mathis et al. 2012).Species of this genus exhibit considerable sexual dimorphism, especially on the width of the body and coloration of the face.
Comments.Planinasus occurs exclusively in the Neotropical Region and currently includes 18 extant and one fossil species.The genus was revised by Mathis et al. (2012) and recoded from Colombia, Belize, Bolivia, Brazil, Costa Rica, Cuba, Dominican Republic, Ecuador, Guatemala, Guyana, Jamaica, Mexico, Panama, Peru, Trinidad and Tobago, and Venezuela.Diagnosis.Planinasus nigritarsus (Figs 13,14) belongs to the nigritarsus species group together with P. argen tifacies and P. insulanus, sharing a mostly yellowish orange antenna with pedicel and basal flagellomere darkened dorsally, a single transverse row of about 8 large facial setae, and fore femur with 1 large posteroventral seta at apical third (Mathis et al. 2012).Additionally, this species can be distinguished from the latter and from the all other species of Planinasus by the following combination of characters, in addition to the characters of the nigritarsus group: ventral receded portion of face short, height shorter than the width of antennal pedicel, and with dense silvery white microtomentum; fore coxa frequently whitish yellow; mid-and hind femora brown with basal third to half yellowish; fore tarsus usually blackish, fore basitarsomere slightly compressed (Mathis et al. 2012).New country record.French Guiana, Montagne des Chevaux, xi.2009, window trap, 04°43ʹ00ʺ N, 052°25ʹ00ʺ W, altitude 90 m, 1 female (NHMUK 0833317), male (NHMUK 0833317).

Discussion
French Guiana is a comparatively small country of 84,000 km 2 in northern South America (Brûlé and Touroult 2014) and is part of the Guiana shield in Northern Amazonia (04°13ʹ N, 052°59ʹ W) (Guitet et al. 2015), bordering with Suriname in the west and with Brazil (Amapá State) in the south and east (Guitet et al. 2013).As part of the large Guiana moist forest ecoregion, French Guiana shares a species pool with adjacent countries (Brûlé and Touroult 2014).Due to the lack of real geographical barriers between French Guiana and neighboring countries (Suriname and Brazil), it is believed that the fauna of French Guiana contains few real endemics (Brûlé and Touroult 2014), as observed for its flora (Granville et al. 1996).In addition, previously known insects from French Guiana are also present in the Amazonian part of Andean countries (Granville 1992).
Five species of Periscelididae were recorded for French Guiana in this paper of which only Marbenia peculiaris was described from a location outside the Amazon sub-region.The type locality of M. peculiaris is located in Panama and this species was also recorded from northern Brazil, Ecuador and Bolivia, in the Amazonian biome (Ale-Rocha et al. 2014).All other species here recorded for the first time from French Guiana have their type localities in northern South America, all within the limits of the Amazonian biome.Thus, their occurrence in French Guiana was expected.Here we record for the first time N. barcelosiensis and N. flavoscutellatus from beyond their type localities.Described from Peru, N. peruvianus has also been recorded in Ecuador and Brazil (Ale-Rocha and Freitas 2011), which suggests its distribution may cover the major part of the Amazon.The same can be suggested for Planinasus nigritarsus, which has already been recorded in Bolivia, Peru and northern states of Brazil, all within the Amazon biome (Mathis et al. 2012).Additional collections in neighboring countries may fill the gaps in the distribution of these species and confirm their probable distribution throughout the entire Amazon.
According to Brûlé and Touroult (2014), in their check list of insects of French Guiana, about 15,100 valid species names allocated in 20 orders and 322 families are known in this country and Diptera is one of the poorest studied orders, with only 577 known species.Recently, the fauna of French Guiana has been more intensively studied, greater surveying efforts of the insect fauna have been carried out (Pollet et al. 2014;2015) and an expressive diversity has been found to other insects (Krolow et al. 2017).
Although this sampling improves our knowledge of Periscelididae, it does not represent the actual diversity of Periscelididae from French Guiana, given the greater diversity of the group in neighboring countries that share the same biome (Ale-Rocha and Freitas 2011, Freitas and Ale-Rocha 2011, Mathis and Rung 2011, Rung and Ale-Rocha 2011, Mathis et al. 2012, Ale-Rocha et al. 2014).Increasing samples from the country will undoubtedly produce a more reliable estimate of the diversity of this family from this part of South America.

Diagnosis.
Neoscutops flavoscutellatus(Figs 9, 10)   belongs to the peruvianus species group (Ale-Rocha and Freitas 2011).This species is similar to N. manaos and N. waorani, having the face brown with an inverted W-shaped yellow spot, but can be distinguished from both by the yellow clypeus, scutellum and femora.Additionally, N. flavoscutellatus differs from other species