Japanagromyza Sasakawa

Sasakawa, Mitsuhiro, 2010, A review of the Oriental Japanagromyza Sasakawa (Diptera: Agromyzidae), with descriptions of four new species, Zootaxa 2485, pp. 16-32 : 17

Genus Japanagromyza Sasakawa

Japanagromyza Sasakawa, 1958: 138 . Type-species: Agromyza duchesneae Sasakawa, 1954: 106 , designated by Sasakawa, 1958.

Geratomyza Spencer, 1973: 140 . Type-species: Geratomyza maculata Spencer, 1973 , by original designation.

Diagnosis. Wing with subcosta coalesced with R1 before reaching costa; halter yellowish white as in species of genus Agromyza Fallén, 1810 , or uniformly dark brown as in those of genus Melanagromyza Hendel, 1920 , or variegated on top or inside of dark knob; fronto-orbital bristles (ors and ori) stronger than those of Agromyza and Melanagromyza ; mesoscutum with two pairs of postsutural dorso-centrals (dc) as in Melanagromyza (rarely three pairs, but anteriormost ones only a little longer than acrostichals), and one pair of prescutellars (prsc, rarely absent) as in Agromyza ; fore tibia usually with lateral bristle at middle (this bristle also found in some large species of Melanagromyza ). Male genitalia: surstylus sometimes elongate (never elongate in Melanagromyza and Agromyza ); hypandrium V- or Y-shaped, bent ventrally, with basal apodeme sometimes long; basiphallus with sclerites short, united or separated at bases (shortly U-shaped in Melanagromyza , long and separate in Agromyza ); hypophallus usually well developed; mesophallus, if present, situated on same plane as basi- and distiphallus (not folded below distiphallus as in Melanagromyza ). Larva: mandible with 2-6 teeth; posterior spiracles with either 3-10 large opening pores in a circle or numerous minute pores around trifurcate branches.

Description. External structure and chaetotaxy of all known species are generally uniform. Specific differences lie principally in color of the halter, and genital structures of both sexes. Descriptions of the new species in the present work only emphasize points of difference from the following generic description. Coloration. Body black, partly yellow in some Neotropical species; ocellar triangle and parafrontalia weakly shining; lunule whitish gray pruinose. Antennae and palpi black, arista sometimes dark brown. Mesoscutum and scutellum densely or scarcely gray dusted, matt or weakly shining, sometimes with greenish, bluish or reddish coppery sheen. Abdomen usually strongly shining, sometimes with coppery sheen. Wings usually hyaline; calypters with whitish or blackish fringe. Legs black, tarsi rarely yellowish brown. Structure. Head with frons as wide as, or slightly wider or narrower than eye, almost parallel-sided. Parafrontalia narrow, usually not projecting above eye-margin in profile; ors and ori each two, reclinate except for shortest second ori incurved; orbital hairs (oh) minute, reclinate, in row; gena narrow, often less than 1/10 as high as eye; vibrissa and several peristomal setae present. Face with narrow and low central carina dorsally. Antenna with first flagellomere small, round, with dense short pile; arista microscopically pubescent or bare. Palpus simple, with several setae apically.

Thoracic chaetotaxy very uniform except in acrostichal (acr, in 6-10 rows) and prescutellar (present or absent) bristling: 1 presutural, 1 intra-alar, 1 supra-alar, 2 post-alars; 1 postpronotal (humeral), 2 notopleurals; 2 pairs of strong scutellars; 1 propleural; anepisternum with short setulae on upper part, 1 strong (mpl) and a few short setae above or below base of mpl; katepisternum with 1 strong (spl) and a few short setae before base of spl. Legs: mid tibia with two postero-dorsal bristles (pd) at middle; hind tibia with cleaning comb of fine bristles just before inner tip ( Tschirnhaus 1991).

Wings 1.5-3.5 mm long, costa extending to M1, crossvein r-m situated before or behind middle level of discal cell, both relative lengths of ultimate and penultimate sections of M1 and CuA1 vary among the species.

Abdomen with six pregenital segments; sixth sternite (S6) deeply incised in median posterior half. Male genitalia: epandrium rounded, ventrally articulated to hypandrium; surstylus either extending downward or inward, varies in shape and spinosity; cercus elongate or broadened ventrally; proctiger varies in shape; phallic hood moderately elongate, either with minute spinules or entirely bare; distiphallus distally with strongly chitinized bulbs or almost membranous tubule(s); ejaculatory apodeme with blade clavate or asymmetric fanlike. Female genitalia: ovipositor sheath shiny, with apodeme subrectangular, pouched at near anterior end; egg guides with many teeth of serrations almost all over outer margins; ninth tergite shorter than U-shaped sternite; cercus with four tactile sensillae on tip; spermathecae two, small, orbicular to ellipsoidal, sometimes scattered minute spinules on surface; ventral seminal receptacle almost colorless, suboval at base, with tail part papilliform to tubular in various lengths.