New species of Cyamops ( Diptera : Opomyzoidea : Periscelididae ) from the old and new world tropics

Two new species of Cyamops Melander are described, one from the Afrotropical and one from the Neotropical Region. The newly described species are (type locality in parenthesis): Cyamops mathisi sp. nov. (Province Fianarantsoa, Madagascar) and Cyamops manauensis sp. nov. (state of Amazonas, Brazil). Both species can be separated from congeners based on characters of the male genitalia, particularly the shape of the surstyli. A new country, the Ivory Coast, is added to the distribution records of Cyamops nigeriensis, previously known only from Nigeria and Namibia. Updated keys to the Afrotropical and Neotropical species of the genus are also given.

Cyamops Melander, 1913 includes 32 valid species: two from the Afrotropical Region, 14 from the Australasian/ Oceanian Region, three from the Nearctic Region, seven from the Neotropical Region, five from the Oriental Region, and one from the Palearctic Region (MATHIS & RUNG 2011, MATHIS & SUEYOSHI 2011).Despite the fact that the taxonomy of the genus has been well-documented in recent years, very little is known about the biology of the included species, and immatures have never been found.Adults have been collected near streams, on rocks in streams, near waterfalls, in marshy habitats (often on broad-leaved plants), and beside pools in almost dry riverbeds (KHOO 1985).
BAPTISTA & MATHIS (1994) last reviewed the Neotropical fauna of Cyamops, and a few new species were later added by the same authors (1996,2000).The two Afrotropical species were described in a single contribution (BAPTISTA & MATHIS 2000).The genus was recently catalogued and its classification was briefly discussed by MATHIS & RUNG (2011).
In this paper we describe two new species, one from Madagascar and one from northern Brazil.We also provide locality data on the discovery of C. nigeriensis Baptista & Mathis, 2000 in the Ivory Coast.The Brazilian specimens were collected as part of an insect survey in the Amazon using Malaise and "Suspensa" traps (RAFAEL & GORAYEB 1982).In order to facilitate identification of the new species, we have updated the keys to the Afrotropical and New World species (modified from BAPTISTA & MATHIS 2000).We also present illustrations of the external morphology and diagnostic structures of the male terminalia of the new species.A diagnosis of Periscelididae, a world key to the included subfamilies, genera and subgenera, as well as a discussion of the taxonomic placement of Cyamops have been recently published (MATHIS & RUNG 2011) and will not be replicated here.The most recent description of the genus can be found in MATHIS & SUEYOSHI (2011).

MATERIAL AND METHODS
The descriptive terminology, with the exceptions noted in BAPTISTA & MATHIS (1994, 2000), follows the Manual of Nearctic Diptera (MCALPINE 1981).For some structures of the male terminalia, we follow the terminology adopted by other workers in Periscelididae (BAPTISTA & MATHIS 1994, 2000, SUEYOSHI & MATHIS 2004, MATHIS & SUEYOSHI 2011).The format for the species' descriptions adheres to BAPTISTA & MATHIS (1994, 2000).Species' descriptions are composite, including information on the holotype and other conspecific specimens.All species exhibit sexual dimorphism to some degree, although not always in the same characters.To account for this variation in the descriptions, we describe the male first, followed by a section on differences in the female.Three wing vein ratios used in the descriptions of the new species are based on the largest and smallest specimens and are defined as: (1) wing ratio: straight line distance between wing base and apex/greatest straight line distance from anterior margin to posterior margin; (2) costal vein ratio I: the straight line distance between the apices of R 1 and R 2+3 (costal section II)/distance between the apices of R 2+3 and R 4+5 (costal section III); (3) costal vein ratio II: straight line distance between the apices of R 2+3 and R 4+5 (costal section IV)/ ZOOLOGIA 28 (6): 803-811, December, 2011 distance between the apices of R 4+5 and M (costal section III).Because specimens are small, study and illustration of the male and female terminalia required use of a compound microscope.Photographs were taken with a Nikon Coolpix Ds-Fi1 digital camera using a Nikon SMZ1500 stereomicroscope.In order to produce final images with most structures in focus, we took several photograph layers of each body part and subsequently assembled them with Combine ZM 2008.The photographs were enhanced, formatted and arranged in Adobe Photoshop 7™ The Brazilian specimens examined as part of this study are deposited in the Instituto Nacional de Pesquisas da Amazônia (INPA), Manaus, and Coleção Zoológica da Universidade Estadual do Maranhão (CZMA), Caxias.Specimens from the Afrotropics are at the California Academy of Sciences (CAS), San Francisco, and the California State Collection of Arthropods (CSCA), Sacramento.

Afrotropical species
With the inclusion of the new species described below, a total of three species of Cyamops are known in the Afrotropical Region, two in Madagascar and one in Nigeria, Namibia and the Ivory Coast (new record, see below).All known Afrotropical species have two spermathecae, a character state common to all Old World species, and lack setae on the posterior dorsal margin of the anepisternum.Cyamops mathisi sp.nov.

Figs 1-10
Description.Male (three specimens measured): Adult length 1.9-2.1 mm; wing length 1.7-2 mm; wing width 0.6-0.75mm.Head: Ocellar tubercle mostly polished, shiny spot on vertex reaching ⅔ distance to eye margin; frons subshiny microtomentose, velvet at deepest portion, parafacial margins densely microtomentose, silver up to just underneath insertion of fronto-orbital setae; antenna mostly yellow, slightly infuscate at dorsal margin of scape; face constricted medially by anteroventral margin of eyes, expanded into a ventral triangular region below level of pseudovibrissae and bearing a vertical, midfacial, yellow carina, facial triangle mostly yellow; gena yellow, when viewed anteriorly conspicuously silvery white microtomentose; palpus and labellum mostly pale yellow; face in profile shallowly and vertically arched, not angulate; eye sparsely microsetulose.Chaetotaxy: Medial fronto-orbital setae slightly divergent; arista with about 8-9: 3 rays, 4-5 basal rays clearly bifurcate; peristomal setae 7-8.Thorax: Mostly brown.Postpronotum subshiny microtomentose; halter mostly white, infuscate at base; mesonotum slightly longer than wide; scutellum trapezoidal, disc flattened.Chaetotaxy: Dorsocentral setae 0+1, subequal in length to the 1 st scutellar seta; few setulae between dorsocentral and acrostichal rows in most specimens; setulae of mesonotum at most ⅓ length of dorsocentral seta; scutellar setae 2 pairs, basal pair about ⅔ length of apical.Legs: Mostly yellow; hind femur brown on apical ½-¾; apical and sometimes subapical tarsomere of each leg brown; spine-like setulae on fore femur 5. Wing: Mostly hyaline, central portion very slightly infuscate with brown; costal vein ratio I: 0.9-1; costal vein ratio II: 3.3-3.7;wing ratio 2.6-3.1.Abdomen (Figs 9 and 10): Coloration as described for the thorax, without pol-ished segments; 6 th and 7 th tergites large, subequal in length; posterior process of 6 th and 7 th sternites as in Fig. 9. Male terminalia as follows (Figs 9 and 10): Left surstylus narrow, in ventral view with base expanded and apex pointing to the left side; right surstylus slightly shorter but considerably wider than left, in ventral view subtriangular with round corners; hypandrium asymmetrical, gonopods not clearly differentiated; ejaculatory apodeme with two main axes making a right angle with one another, longest axis triangular in dorsal view, as long as right surstylus, shorter axis mostly parallel-sided with subapi-  Distribution.Afrotropical: Ivory Coast, Nigeria, Namibia.Remarks.This species was previously only known from Nigeria and Namibia, and its discovery in the Ivory Coast extends our knowledge of this species' distribution.

Neotropical species
With the inclusion of the new species described below, a total of 11 species of Cyamops are known in the New World.Of these, eight occur in the Neotropical Region.Females of all Neotropical species that have had their abdomens dissected (four species total) have four spermathecae.This number contrasts with the two/three spermathecae found in species from other regions and is a putative synapomorphy for the Neotropical fauna.Remarks.In the key above, the two species referred to as "1" and "2", from Trinidad and Panama, respectively, were not named by BAPTISTA & MATHIS (2000) because the specimens available were few and in their condition precluded a thorough description.We have kept these species in this revised "Key to New World species of Cyamops" in the hope that further collecting in those countries will produce more specimens, and that one day they can be described and have their names in the appropriate couplets.

Key to New World species of Cyamops
Cyamops manauensis sp.nov.
Female (two specimens measured): Adult length 2.6-2.7 mm; wing length 2.5-2.8mm; wing width 0.9-1 mm.Head: Ocellar tubercle polished and shiny spot on vertex more extensive.Antenna with dorsal ½ and apex of 1 st flagellomere brown; face mostly dark brown, not constricted medially by the eyes, bearing a more elevated, parallel, central region (a broad carina); facial carina mostly polished, encroached by lateral microtomentum basally; gena and lateral portions of face below level of pseudovibrissa strongly microtomentose; palpus brown; face in profile angulate, sloped anteroventrally from base of antenna to vibrissal angle, thereafter slightly receded to oral margin; arista with 13-14 dorsal rays.Thorax: Dorsocentral setulae typically better developed than in the males.Abdomen (Fig. 18): Demarcation between tergites 7 and 8 sharp dorsally; sternite 8 fused to 7 th ; 4 spermathecae present, oblong, one pair slightly smaller than other, apical portion of spermathecal ducts sclerotized.
Type material: The holotype male is labeled "BRA     (2000), are difficult to separate based on external characters.They all share a similar wing pattern (with cell r 4+5 completely infuscate dividing subapical white spot) and coloration of the legs.For this reason, dissection of the male terminalia is essential to differentiate each of them.