Amapeza, Marshall, 2022

Marshall, Stephen A., 2022, Amapeza and Nigripeza, new genera of Neotropical micropezid flies (Diptera, Micropezidae, Taeniapterinae), Zootaxa 5092 (3), pp. 251-272 : 252-253

Amapeza new genus

Type species: Systellapha amazonica Enderlein, 1922 .

Generic description: Body length 7–11 mm. Colour: Frontal vitta uniformly dull orange. Orbital plate orange pruinose, barely differentiated from frontal vitta; epicephalon shiny orange, ocellar plate small and black. Palpus black with a contrasting white ventral margin. Thorax usually mostly orange (but see A. camelina ). Fore tarsomeres white but tarsomere 5 and sometimes tarsomere 4 slightly darkened. Hind femur pale brown, in most species with a distinct preapical pale band (band absent in A. camelina ). Wing mostly clear or with a broad but weak discal band. Abdominal pleuron usually with a characteristic area of dark pigmentation; male with a distinct dark pleural sac on P2 or P1–2.

Head:Arista pubescent, longest hairs no more than 1/4 of scape width.Pedicel with one or more long ventroapical bristles, usually subequal to first flagellomere. Frontal vitta parallel sided behind ocelli, slightly broadened before ocelli, variably tapered anteriorly. Clypeus shining, usually entirely bare (microsetulose in A. tricincta n.sp.). Palpus broad but strongly tapered apically. Three similarly well-developed fronto-orbital bristles; inner vertical, outer vertical and postocellar bristles present and strong.

Thorax: One or two dorsocentral bristles. Suprahumeral bristles small and exclinate, usually 3–5 with anterior largest, sometimes absent. Wing with long inclinate dorsal costagial bristle and somewhat shorter ventral costagials.

Female abdomen: Major (paired) spermathecal duct long and distally swollen with a truncate apex from which the stout, twisted or sinuate spermathecal stems arise; paired spermathecae large, distally expanded with apex normally invaginated. Minor (single) duct greatly reduced or vestigial, single spermatheca small.

Male abdomen: Epandrium and distiphallus long, basal distiphallus longer than epandrium; phallic bulb usually indistinct, distal distiphallus long and (in species other than A. affinis ) with a conspicuous, sometimes spinulose, apical swelling ("glans").

Etymology: A number of widely separated clades traditionally treated as part of Grallipeza have been informally organized for several years using manuscript names with the suffix " peza ". Two of those clades are formally named using this suffix here, with the prefix " Ama " applied to this group of orange species with the type species Amapeza amazonica .

Comments: The female and male genitalia of Amapeza species , especially the long distal distiphallus and greatly reduced third spermatheca, are distinct from other taxa previously treated as Grallipeza . CO1 sequences (barcodes) for A. plicata , A. amazonica and A. camelina suggest that the species of Amapeza form a monophyletic group that is widely separated from other species previously treated as Grallipeza , and an unpublished analysis using multiple genes (12S, three segments of the gene 28S referred to as 28S– 2, 28S –3 and 28S–5 and CO1–3′) recovers the three included species of Amapeza as the sister group to Systellapha plus a large undescribed genus (Lindsay and Marshall, in manuscript). The same analyses recover Grallipeza ss as the sister group to Calosphen Hennig.

Key to the species of Amapeza

1. Two dorsocentral bristles ( Fig. 5E ). Mid and hind femora yellow-brown, sometimes with an indistinct pale distal band ( Fig. 5E )................................................................................................ 2

- One dorsocentral bristle. Mid and hind femora brown with a pale base and a distinct white band in distal half ( Fig. 1C )....4

2. Postpronotum with an elevated setulose posterior ridge or hump (prominent and obvious in females ( Fig 5E ); less so in males, Fig. 5A )...................................................................... Amapeza plicata new species

- Postpronotum evenly rounded posteriorly.................................................................. 3

3. Most of thorax and abdomen dark brown, with only margins of notum and sides of oviscape orange ( Fig. 3A ). Oviscape with a prominent and conspicuous dorsal hump near base ( Fig. 3B ).......................... Amapeza camelina new species

- Most of thorax and abdomen orange ( Fig. 4E ). Oviscape without a dorsal hump near base..... Amapeza hyaloptera (Hendel)

4. Frontal vitta strongly tapered anteriorly, width at anterior margin much less than distance between anteroventral corner of frontal vitta and eye. Proepisternum with 1-3 very long bristles at posterior corner, at least one twice as long as anterior ventral proepisternal bristles. Female abdominal pleuron densely setulose, male abdominal pleuron setulose to almost bare. Distiphallus recurved and terminating in a conspicuous swelling ( Fig. 2G )........................................ 5

- Frontal vitta weakly tapered anteriorly, width at anterior margin approximately equal to distance between anteroventral corner of frontal vitta and eye ( Fig. 1B ). Proepisternal bristles forming a continuous ventral row of subequal bristles. Abdominal pleuron of both sexes bare. Distiphallus extremely long, threadlike, not swollen distally ( Fig. 1H ). Amapeza affinis (Hennig)

5. Clypeus dull, entirely microsetulose. Hind tibia with three distinct dark rings ( Fig. 6A ). Posterior vertical row of katepisternal bristles brown. Male genital fork without processes at inner bases of arms ( Fig. 6D ).................. Amapeza tricincta

- Clypeus shining, entirely bare. Hind tibia with only basal and distal rings, middle area with diffuse pigmentation.All katepisternal bristles golden. Male genital fork with prominent processes at inner bases of arms ( Fig. 2D )..................................................................................................... Amapeza amazonica (Enderlein)

Figures

FIGURES 1A–1H. Amapeza affinis (Hennig) A, head, lateral; B, C, living female, Brazil; D, male sternite 5 (genital fork); E, spermathecae and associated ducts; F, Detail of apical part of paired spermathecal duct and spermathecae; G, male terminalia, left lateral.

FIGURES 2A–2H. Amapeza amazonica(Enderlein).A, spermathecae andassociated ducts; B, inset, oviscapewith spermathecae and associated ducts teased out; C, apex of male abdomen, ventrolateral to show genital fork; D, genital fork, ventral; E, female showing setulose abdominal pleuron, Ecuador; F, holotype. G, male terminalia, left lateral; H, head anterior.

FIGURES 3A–3G. Amapeza camelina new species. A, female, Ecuador; B, female abdomen to show humped oviscape; C, male sternite 5 (genital fork); D, male terminalia, left lateral; E, male abdominal segments 4, 5 and terminalia, ventral; F, spermathecae; G, spermathecae and associated ducts.

FIGURES 4A–4E. Amapeza hyaloptera (Hendel). A, male sternite 5 (genital fork); B, male terminalia; C, distal part of distiphallus; D, spermathecae and associated structures; E, living male, Brazil. Abbreviations: bdp—basal distiphallus, ddp— distal distiphallus, pb—phallic bulb, ps1 and ps2—paired spermathecae, ss, single spermathecal duct.

FIGURES 5A–5F. Amapeza plicata new species, A, living male, Bolivia; B, male sternite 5 (genital fork); C, male terminalia, left lateral; D, female to show wing pigmentation; D, living female, Bolivia.

FIGURES 6A–6F. Amapeza tricincta new species. A, male holotype B, female paratype; C, male terminalia; D, male sternite 5 (genital fork); E, spermathecae and associated structures, lateral; F, spermathecae and associated structures; dorsal.