Dicranophora femurspiculata, Godoi, Fabio Siqueira Pitaluga De & Rafael, José Albertino, 2013

Godoi, Fabio Siqueira Pitaluga De & Rafael, José Albertino, 2013, A new species of Dicranophora Macquart (Diptera, Stratiomyidae) from Bahia State, Brazil and a key to species of the genus, Zootaxa 3641 (1), pp. 83-91 : 85-90

Dicranophora femurspiculata sp. nov. Godoi & Rafael

Figures 2–16

Diagnosis. Dicranophora femurspiculata sp. nov. is characterized by two dark spots on the frons, a larger one that reaches the eyes and almost reaches the smaller spot, positioned slightly above the base of the antenna; scutellum with a large forked scutellar process; yellow legs with dark brown fore tibia and brown hind tibia; white tarsi with fourth to fifth tarsomeres dark brown; mid femur with a large thorn and a series of small denticles on ventral surface and abdominal terga yellow-greenish with dark brown to black spots on light brown bands, except tergite 5 without spots.

Description. Holotype male. Body length 6.7 mm (excluding antennae) ( Fig. 2 ).

Head ( Figs. 3-4 ) rounded and green with black spots on the frons. Eyes blackish, dichoptic and bare. Vertex with prominent black ocellar tubercle, ocelli well developed and yellowish. Frons with upper two thirds subparallel-sided, the lower third with sides slightly divergent; two dark spots present ( Fig. 3 ), the larger one occupies the middle region and touches the eyes; lower-median downward, narrowing gradually until it almost touches the second spot; the lateral margins of the larger spot projected upward along the ocular margin up to the vertex; the second spot is located slightly above the base of antenna, in the middle portion on the lower third of the frons, and has a narrow projection that extends between the antenna but never touching them; frons with hair-like setae greatly reduced, short and light-colored, not visible in frontal view, giving a false impression that the integument is bare. Face slightly wider than frons, with long dense and silver-colored hair-like setae, except the middle portion with sparsely scattered hair-like setae. Antenna ( Fig. 5 ) dark brown, scape slightly narrower than pedicel; pedicel nearly spherical, slightly wider than long; scape and pedicel with distinct black hair-like setae; flagellum as long as wide, approximately the same length as the scape; pedicel with a strong excavation on the inner side; flagellomeres strongly fused, making it difficult to observe any discrete flagellomeres, and with inconspicuous hair-like setae; flagellum with long apical arista-like stylus, almost two times longer than the antennal segments combined. Mouthparts brown with yellow labellum and golden vestiture, palpus absent - a ventral projection of the head covers the entire area where the palpus would be located making it difficult to know if they are reduced or absent without dissection.

Thorax ( Fig. 6 ) with pronotum and postpronotal lobes green; pronotum also with a narrow black band at the posterior margin. Mesonotum black with postalar callus and scutellum green, scutum marked with a pair of stripes; pubescence of the mesonotum very short and light-colored, barely perceptible in dorsal view. Scutellum green and subtriangular with straight base and apex with a large median forked process ( Fig. 7 ); scutellar process brownish and cylindrical, with a large V-shaped fork in the apical portion, each arm with pointed apex; scutellar process (main branch + fork) long, slightly shorter than the length of the abdomen and projected upwards forming an angle of about 45 degrees with the body; forked portion of the process longer than main branch; anterior third of the main branch with well developed protuberances with hair-like setae at the apices, the remainder of the main branch and the entire forked portion with small and spaced protuberances. Laterotergite yellow-greenish, with a well developed conical projection with pointed apex at posteroventral portion of the sclerite. Pleura yellowish with greenish parts in the upper portions and large black spots throughout proepimeron, at the upper margin of proepisternum, at the anterior and median portions of anepisternum, at the anterior and lower margins of katepisternum, at the anterior half of anepimeron and anterior margin of meron. Prosternum with two rounded yellow spots on the middle portion. Mesosternum black with a narrow yellowish stripe. Metasternum dark brown.

Wings ( Fig. 8 ) hyaline, blades covered with microtrichia, three times longer than wide, slightly shorter than the length of the body and with rounded apex. Vein C, apical portion of Sc, R, R1, R4+5, Cu and crossvein r–m covered with dark and relatively long hair-like setae. Pterostigma in cell r1. Veins well defined, light brown, except vein Sc, crossvein h, proximal portion of Rs, R2+3, M and apex of R1, M1, M2, CuA1 and A1+CuA2 barely visible and usually without pigmentation. Vein Sc very close to R, arched in the middle portion and ending in R just before the first bifurcation. R1 almost straight reaching the costal margin obliquely. R2+3 short, almost transverse, reaching the costal margin practically together with R1. R4+5 reaching costal margin near the apex of the wing. Cell bm slightly longer than br. Crossvein r-m long and placed at the base of cell dm. Cell dm short, sub-pentagonal and twice longer than wide. Veins M1 and M2 arise relatively close together, with the apical portion poorly defined giving a false impression that the veins do not reach wing margin. M1 slightly arched anteriorly and M2 straight and wider than M1. Vein M3 straight and narrower than veins M1 and M2, not reaching wing margin. Crossvein m-cu slightly longer than r–m. Vein CuA1 almost straight, reaching wing margin. Vein CuA2 slightly arched, fused apically to A1, forming A1 + CuA2 which is short and reaches wing margin obliquely. Halter relatively long with stem brown and an ovoid green knob, twice longer than stem.

Legs long with coxa and trochanter yellow-whitish, femora and tibiae yellowish, except fore tibia dark brown and hind tibia brownish; tarsi whitish, fourth and fifth tarsomeres dark brown. Legs with hair-like setae having the same color like the integument of the corresponding segment, except, proximal three tarsomeres of the foreleg with dark brown hair-like setae, giving the impression that the tarsomeres are brown. Coxae relatively long with the fore coxa larger and the mid coxa smaller. Fore and hind trochanter subequal and shorter than mid trochanter, which is elongated with an acuminate extension on anterior portion forming a kind of spur projected downward. Femora slightly longer and wider than the tibiae, with mid femur larger and fore femur smaller; mid femur ( Fig. 9 ) with a large ventral thorn in the middle portion, longer than the greatest width of femur and curved toward apex of femur; the large thorn is preceded in the proximal half of the mid femur by a series of 18 small denticles. Tibiae long with anterior portion slightly narrower; fore and hind tibiae subequal and much smaller than mid tibia. Tarsi long, with fore tarsus larger and hind tarsus smaller; first tarsomere very long, almost as long as the other tarsomeres combined, except mid tarsus with first tarsomere slightly larger than others; first tarsomere of hindleg with long hair-like setae forming a distinct tuft on proximal half of ventral surface ( Fig. 2 ); second tarsomere of the same size as the third and fourth tarsomeres combined; fourth tarsomere very small, about half the size of the third tarsomere, fourth and fifth tarsomeres combined are the same size as second; fifth tarsomere reduced and having the same size as third.

Abdomen ( Fig. 10 ) long, widening posteriorly. Vestiture of tergites composed of short light-colored hair-like setae, almost invisible in dorsal view. Tergites yellow-greenish with dark brown to black spots and light brown bands. Tergite 1 with two small nearly spherical spots near the lateral margin anteriorly; posterior margin of tergite 1 and anterior half of tergite 2 with two large nearly spherical spots that are almost touching on the middle portion, located on a band that reaches the lateral margin of the tergite. Tergite 3 with two nearly spherical spots in lateromedial portion of the anterior half and also on a band; the band does not go beyond the sides of the spots and the middle portion protrudes posteriorly. Tergite 4 as tergite 3, but the spots are semi-spherical and the band on which they are located extends beyond the spots, almost reaching lateral margins while projection at the middle portion reaches the posterior margin. Tergite 5 without spots but with a band occupying almost the entire tergite except the lateral margins, assuming a triangular shape.

Terminalia: Epandrium ( Figs. 11–12 ) longer than wide, anterior margin U-shaped, posterior margin rounded and lateral margins arcuate; posterior third covered with dense setulae with three long posteromedial setulae and three long setulae on posterolateral margins (not depicted in the figures). Proctiger with epiproct and paraproct well defined ( Figs. 11–12 ); epiproct sub-pentagonal with anterior margin V-shaped, lateral margins divergent and posterior margin subtriangular with apex rounded and slightly bilobed; epiproct covered with very short setulae interspersed with long setulae, except the anteromedial portion. Paraproct longer and narrower than epiproct with anterior margin concave and, especially the middle portion, strongly projected ventrally, lateral margins parallel and posterior margin sub-triangular with pointed apex; paraproct covered by long setulae on the sides and apex of the posterior two thirds. Cerci ( Figs. 11–12 ) one-segmented, with apices rounded and convergent with apices slightly passing the posterior margin of epiproct. Phallic complex ( Figs. 13–14 ) long and trifid, mostly fused except apically, with median lobe slightly longer than the lateral lobes and with apex almost straight and narrow; lateralventral surface of the phallic complex with a series of denticles directed posteriorly that gives a saw-like aspect in lateral view; anterior portion enlarged with a large opening showing a nearly spherical sperm sac marked by a series of thorn-like projections linked to a narrow sperm duct; attachment structures elongated and U-shaped with middle portion narrow and posterior portion enlarged ending in a pointed apex. Genital capsule (hypandrium + gonocoxite + gonostylus) ( Figs. 15–16 ) sub-quadrangular, with anterior portion narrower than the posterior and lateral margins slightly arcuate. Hypandrium with anterior margin U-shaped and posterior margin projected upward with the extremity bent, serving as a support for a concave base with apex slightly pointed and slightly divided where the phallic complex fits. Gonocoxites narrow with arcuate lateral margins, anterior margin tapered and posterior truncated; anterior half with narrow, long convergent gonocoxal apodemes with tips that diverge slightly, passing anterior margin of genital capsule. Gonostylus long and well developed with posterior third strongly curved upward forming a kind of a hook with a pointed apex; ventral portion of gonostylus with a finger-like process, resembling a boot when observed in lateral view.

Female. Unknown.

Geographical records. Brazil (Bahia state).

Specimens examined. Holotype 3 (pinned): BRASIL, BA [Bahia state], Encruzilhada [Encruzilhada district], 15º32’25”S, 40º50’12”W, 11.xii.2007 / Rede de varredura, sobre a vegetação [= captured with sweeping net, on vegetation], J. A. Rafael col. (printed white label)/ Dicranophora femurspiculata Godoi & Rafael , HOLÓTIPO [HOLOTYPE] (printed red label). Deposited at INPA.

Paratypes 3 (pinned): Same data as holotype. (printed white label)/ Dicranophora femurspiculata Godoi & Rafael , PARÁTIPO [PARATYPE] (printed yellow label). (3 3 —INPA; 1 3 —CZPB; 1 3 —MZUSP).

Etymology. From Latin, spicula = diminutive of spica, pointed. –ata = suffix meaning carry. This refers to the distinctive thorn of the mid femur.

Remarks. Dicranophora Macquart species are known mainly from type-material and from a few additional specimens deposited in scientific collections so that virtually all knowledge about the known species derives from the original descriptions. This lack of knowledge also holds true for the entire subfamily.

Biological, ecological and behavioral aspects are unknown for the subfamily, as well as a potential economic importance in the agricultural and medical-sanitary context. Nothing is known about the larvae of Raphiocerinae with exception of Raphiocera armata ( Wiedemann, 1830) collected on a decaying tree trunk. Although they were found in a terrestrial environment they possessed hydrophobic plumose bristles on the margin of the posterior spiracle, a feature of aquatic stratiomyid larvae (Pujol-Luz et al. 2004). Thus, although not strictly aquatic, these larvae seem to be associated with wet environments.

Aspects of the biology of adults are unknown and subfamily records are restricted to observations of these insects flying over or resting on vegetation. The males of Dicranophora femurspiculata sp. nov. observed in the field by the junior author rested on undergrowth and shaded bushes, possibly defending small territories that could be used as mating sites.

Specimens of Raphiocerinae stored in collections consist of dark colored flies marked by spots and stripes of yellow, green or even white color. In life Raphiocerinae possess shining green spots and/or stripes. The green color usually changes to yellow-greenish, yellow-whitish or white due to prolonged storage or the action of ethyl acetate or alcohol. To Dicranophora femurspiculata sp. nov. described here, the action of ethyl acetate changed the color pattern of some parts of the body to a yellow-greenish or yellow color. Such pattern does not represent the real condition of this species in life which exhibited shinning green coloration.

Figures

FIGURES 2 – 10. Dicranophora femurspiculata sp. nov. (Holotype). 2, Habitus (wings removed); 3, Head, frontal view; 4, Head, dorsal view; 5, Antenna; 6, Thorax, dorsal view; 7, Scutellum + scutellar protuberance; 8, Wing; 9, Midleg, posterior view; 10, Abdomen, dorsal view (setae omitted).

FIGURES 11 – 16. Dicranophora femurspiculata sp. nov. (Paratype). 11, Epandrium, proctiger and cerci, dorsal view; 12, Epandrium, proctiger and cerci, lateral view; 13, Phallic complex, dorsal view; 14, Phallic complex, lateral view; 15, Genital capsule, dorsal view; 16, Genital capsule, lateral view.