Evertomyia irwini, Gaimari, Stephen D., 2004

Gaimari, Stephen D., 2004, A new genus of Lauxaniidae (Diptera) from New Caledonia, Zootaxa 449, pp. 1-39 : 23-28

Evertomyia irwini , sp. nov.

( Figs. 1 , 10 A–E, 11A–C)

Etymology. Named for my good friend and mentor, Dr. Michael E. Irwin, who was one of the collectors of this and other species of this genus.

Diagnosis. Like E. albeto , E. helenae , and E. matilei , this species has strong, proclinate, parallel­sided ocellar setae, silvery grey pruinescence on the fronto­orbital plate (although unlike E. helenae , this pruinescence covers it entirely), and paired spots on the ventral part of the face. Like E. albeto , silvery grey dorsocentral vittae are present but are narrower than that species, with a width equal to one­fifth the distance between vittae; and vittae extend through the scutellum, but unlike that species they extend only along the lateral edge, and the posterior edge is pale yellow from posterior view. Like E. helenae and E. matilei , the ptilinial suture is dark brown to black pruinose only along the dorsal part terminating above the level of paired facial spots, and the antennal groove has a distinct dark brown to black mark extending medially from the dorsal part of this suture. Like E. helenae , E. matilei , and E. webbi , the anterior orbital seta is closer to the lunule edge than to the posterior seta. Like E. helenae and E. webbi , the antennal arista is short plumose. Like all species except E. frankadelia , the orbital setae are strong with the posterior seta slightly stronger than the anterior seta, and the anterior dorsocentral seta is closer to the transverse suture than to the middle seta. Like all species except E. albeto , the face lacks a median spot and the midtibia has 1 strong spur. In the male: sternites 2–5 are 2 X wider than long; the surstylus is long and strap­like, gradually curved medially, with the outer surface setose and pilose, the inner surface is bare, and the tip is bare and curving to a sharp medially hooked point; the aedeagus is slightly tapered distally, the ventral surface has paired ridges forming a median furrow; the hypandrium is a broad band with the anterior and posterior edges parallel, with 1–2 small setulae posterolaterally; the paramere is present, tusk­like, and curved outwards, with 1 small setula at the base beside the hypandrial setula. In the female: sternites 2–5 are 2– 3 X wider than long; syntergosternite 7 has a longitudinal dark mark lateral of the spiracle; sternite 8 is as wide as long, with posteriorly­directed lateral arms and an anteriorly­directed medial extension, and the paired central processes are slightly elongated, lacking a distal hook.

Adults, ɗ, Ψ. Body ( Fig. 1 ) length 5.7–6.8 mm.

Head ( Fig. 3 D). 1.1–1.3 X higher than long, 1.4–1.7 X wider than high; eye as high as long. Vertex with light dusting of silvery grey pruinescence; outer vertical seta as strong as posterior orbital seta, inner seta 1.4–1.5 X longer. Ocellar triangle covered with same silvery grey pruinescence as vertex. Ocellar setae strong; proclinate, parallel­sided. Postocellar setae strong, nearly as strong as ocellar setae. Occiput and median occipital sclerite orange, with light dusting of silvery grey pruinescence. Frons with anterolateral part with brown pruinose spot visible in profile below fronto­orbital plate. Fronto­orbital plate densely covered with silvery grey pruinescence. Orbital setae strong; posterior seta 1.0– 1.2 X longer than anterior; anterior seta arising slightly closer to edge of lunule than to posterior seta; distance between anterior setae subequal to that of posterior setae. Antennal scape, facial carina, and area lateral to antennal base pale yellow, with light dusting of silver pruinescence. Antennal pedicel and 1st flagellomere orange; 1st flagellomere 1.3–1.4 X longer than high; arista short plumose, with longest rays 0.7–1.1 mm and 0.4–0.6 X height of 1st flagellomere. Face yellowish orange, with light dusting of silver pruinescence; antennal grooves with dark brown to black pruinose area below antenna and along dorsal part of ptilinial suture; ventral part of face with paired dark brown pruinose spots. Parafacial, gena, and postgena yellowish orange with light covering of silver pruinescence. Clypeus yellowish orange. Maxillary palpus dark orange, darkening distally, darkest at tip; subcylindrical; with black setulae.

Thorax. Scutum 1.1–1.3 X longer than wide; scutellum with width at base 1.2–1.4 X greater than length; scutum and scutellum orange; narrow silvery grey dorsocentral vittae present (width of vitta = one­fifth width of orange area between vittae), extending through scutellum along lateral edge; some specimens with thin, slightly lighter median longitudinal line; posterior edge pale yellow from posterior view; postpronotal lobe through notopleuron to wing base yellow pruinose. Dorsal three­quarters of anepisternum and stripe through katepisternal setae orange, as on scutum; remainder of pleural area pale silvery yellow pruinose. Distance between dorsocentral setae subequal, with anterior seta closer to transverse suture than to middle seta. Legs. Yellowish orange, except as noted. Coxae yellow, with light dusting of silvery white pruinescence. Forefemur with patch of silvery brown pruinescence on anterodorsal surface; ctenidium as evenly spaced (each 0.25–0.33 mm apart) row of 9–12 setulae; posterior surface with short row of small setae. Foretibia with brown bands sub­basally and apically. Midfemur with brown spot at midpoint, on ventral surface. Midtibia with brown bands basally, sub­basally, and apically. Hindfemur with brown pruinose band on anterior and anteroventral surfaces beyond middle and apically. Hindtibia with silvery brown bands sub­basally (corresponding in position with band on femur) and apically; with 1 strong spur. Wing. Length 5.2–6.2 mm; 2.5– 2.8 X longer than high. Discal medial cell 4.0–4.4 X longer than crossvein dm­cu. Halter yellow.

Abdomen. Yellowish orange; slightly shorter than scutum. Transverse rows of long setae along posterior edges of tergites becoming longer and stronger laterally. Lateral portion of tergite 1 (as part of syntergite 1+2) with dark silvery grey pruinose patch; lateral portions of tergites 2–5 silvery white pruinose, with brown spot visible from ventral view near tergal edge, and another brown spot visible from dorsal view (both spots visible from lateral view ( Fig. 1 )). Sternites yellow with dusting of silvery white pruinescence; with sparse fine setulae; in male, sternites 2–5 2 X wider than long; in female, sternites 2–5 2.4 X wider than long, with elongated setae along posterior edges. In female, syntergosternite 7 with dark longitudinal mark lateral of spiracle.

Male genitalia. Surstylus articulated with epandrium ( Figs. 10 D–E); long, strap­like, gradually curved medially and tapering distally; outer surface setose and densely pilose, inner surface bare; tip bare except for few tiny hair­like setulae; curving to sharp medially hooked point. Aedeagus ( Figs. 10 A–B) evenly thickening through basal two­thirds, then tapering slightly distally; ventral surface with paired wing­like ridges forming median longitudinal furrow; dorsally with median longitudinal ridge. Hypandrium ( Fig. 10 A) a broad band with anterior and posterior edges parallel; posterolaterally with 1 small setula. Paramere ( Figs. 10 A, C) present, tusk­like, curved outwards; with 1–2 small setulae at base beside hypandrial setula. Aedeagal apodeme normal, thick; branched posteriorly into 2 arms, appearing as “Y” with posterior tips enlarged; curvature such that ventral surface concave from lateral view. Ejaculatory apodeme subequal; bilobed anteriorly.

Female terminalia . Sternite 8 ( Figs. 11 A–B) as broad as long, parallel­sided; with only posteriorly­directed lateral arms and small anteriorly­oriented medial extension sclerotized, posterior half of each lateral arm most darkly sclerotized; paired central processes originating at anterior base of sternite 8, short (but longer than wide) and ending before posterior edge of sternite, lacking distal hooks; process medially fused through basal twothirds, setose. Spermathecae round; single spermatheca 0.12 mm diameter, paired 0.09 mm each; paired spermathecae on short stalks after bifurcation.

Immatures. Egg. Micropylar end enlarged, globose ( Fig. 11 C). Eclosion end with distinct lobes, 3 on each side.

Biology. Specimens of this species have been collected in all months from August through March, except September. This species is attracted to human feces and wallaby dung, but has been most commonly collected using Malaise traps, often across forest paths and along streams.

Type material. Holotype ɗ (pinned, very good condition) deposited in MNHN with the following labels: “ NEW CALEDONIA / Mt. Khogis, 500 m / 17 km NNE Nouméa / 22 December 1991 / M.E. Irwin, D.W. Webb”, “Malaise Trap / across forest / stream”, “ HOLOTYPUS / Evertomyia / irwini / Gaimari ɗ” (red label). Paratypes. Province Nord. 13 km SE Kaala­Gomén, 20°46'07"S, 164°27'26"E, 100 m (M.E. Irwin, D.W. Webb), small Malaise trap across road in dry shrub, 20.I.1996 [1ɗ (dissection 901: SDG 001001)]. Pouebo, 100 m (R. Straatman), Malaise trap, 27.I.1964 [1Ψ]. Province Sud. Between Plum & Yati [Yaté] (T. C. Maa), 25.III.1968 [1Ψ]. Col d’Amieu, Rte. [= Route] Canala [Canala Road], 300–350m (L. Matile), bord de ruisseau [stream edge], 12.XII.1983 [1ɗ]. Mont Dore (north side), 4 km NW Plum (M.E. Irwin, D.W. Webb), Malaise trap in dry wash with pools, 19.XII.1991 [1Ψ]. Mont Dzumac road, 22°03'S x 166°28'E, 700 m (G.B. Monteith), human dung trap, site 8737, 31.X–1.XI.2001 [1Ψ]. Mt. Koghi: 380 m (J.L. Gressitt & T.C. Maa), light trap, 18.III.1968 [1ɗ]; 400–600 m (N.L.H. Krauss), II.1973 [1ɗ]; 500 m (J. & M. Sedlacek), 27.X.1967 [1ɗ], (M. Sedlacek), 23–27.VIII.1967 [1ɗ, 1Ψ], (R. Straatman), 28.XI.1963 [1Ψ], 29.XI.1963 [1ɗ], (R. Straatman), Malaise trap, 2.XII.1963 [21ɗ, 13Ψ], 4.XII.1963 [10ɗ, 5Ψ, 1? (abdomen gone)], 7–8.XII.1963 [1Ψ], (C. Yoshimoto & N. Krauss), Malaise trap, 26–30.I.1963 [47ɗ, 4Ψ]; 500–550 m (N.L.H. Krauss), XII.1983 [1ɗ]; 500–700 m, (R. Straatman), 1.XII.1963 [2ɗ, 1Ψ]; 500–700 m (R. Straatman), Malaise trap, 1.XII.1963 [7ɗ, 4Ψ]; 500–750 m (J. & M. Sedlacek), 25– 26.X.1967 [1ɗ]; 500–800 m (J. & M. Sedlacek), 23–27.X.1967 [1ɗ]; ± 600 m (R. Straatman), 30.XI.1963 [1ɗ, 1Ψ]; (C.M. Yoshimoto), 27.I.1963 [1ɗ], 15.II.1963 [1ɗ], (C. Yoshimoto & N. Krauss), Malaise trap, 27.I.1963 [4ɗ], (N.L.H. Krauss), 28.I.1962 [1ɗ], II.1962 [4ɗ, 1Ψ], III.1959 [1ɗ], III.1978 [1ɗ, 1Ψ]. Mont Koghis [Koghi], 17 km NNE Nouméa: 22°10'34"S, 166°30'17"E, 425 m (M.E. Irwin, D.W. Webb, E. I. Schlinger), Malaise trap across path in rainforest, 8–10.I.1996 [2ɗ], 10–11.I.1996 [1ɗ], 22–24.I.1996 [1ɗ], 24–25.I.1996 [1ɗ], 25.I.1996 [1ɗ, 1Ψ], 27–29.I.1996 [2ɗ]; 22°10.567'S, 166°30.293'E, 550 m, Malaise trap (M.E. Irwin, D.W. Webb), 14–16.XI.1998 [2ɗ, 2Ψ], 18.XI.1998 [1ɗ, 1Ψ]; 350 m (M.E. Irwin, D.W. Webb), Malaise trap, 26.XII.1991 [1Ψ]; 500 m (M.E. Irwin, D.W. Webb), Malaise trap in tropical forest, 30–31.X.1992 [8ɗ, 4Ψ (dissection 902: ɗ, SDG 01002)], (D.W. Webb), Malaise trap in tropical forest, 5– 15.XI.1992 [1ɗ, 1Ψ]; (same collection data as holotype) 500 m (M.E. Irwin, D.W. Webb), Malaise trap across forest stream, 22.XII.1991 [20ɗ, 19Ψ (dissection 911: Ψ, SDG 01012)], 23–26.XII.1991 [2ɗ, 2Ψ], 24–26.XII.1991 [5ɗ]; 500 m (M.E. Irwin, D.W. Webb), Malaise trap across forest path, 27–28.XII.1991 [2ɗ, 1Ψ]; (M.E. Irwin, D.W. Webb), Malaise trap across forest stream, 27–28.XII.1991 [1ɗ, 1Ψ]; 22°11'S x 166°01'E, 500 m (G.B. Monteith), Wallaby dung trap, site 8914, 26–27.I.2002 [3ɗ], 28–29.XI.2001 [1Ψ]. Monts des Koghis, 200–400 m (N.L.H. Krauss), I.1969 [1ɗ], 400–600 m (N.L.H. Krauss), I.1969 [9ɗ, 2Ψ]. Ningua Reserve Camp: 21°45'S x 66 °09'E, 1100 m (G. B. Monteith), human dung trap, site 8640, 12–14.XI.2001 [2ɗ]. Plaine des Lacs area (C.R. Joyce), 5.XI.1958 [1Ψ], 6.XI.1958 [2ɗ, 1Ψ], fly trap baited with human excrement, 5.XI.1958 [13ɗ, 11Ψ]. Plaine des Lacs (C.R. Joyce), 30.X.1958 [1ɗ, 2Ψ]. Rivière Bleue Provincial Park: 212 m (E. & M. Schlinger, D.W. Webb), 20–28.XI.1992 [1ɗ]; 30 km NW Yaté, 270 m (M.E. Irwin, D.W. Webb), 27.XII.1991 [2ɗ, 1Ψ], 550 m, (M.E. Irwin, D.W. Webb), Malaise trap across forest path, 27–28.XII.1991 [2ɗ, 1Ψ]; 35 km NW Yaté (M.E. Irwin, D.W. Webb), Malaise trap across forest path, 27–28.XII.1991 [1ɗ]; km 19.6 Riv. [= Rivière] Bleue road, 183 m (D.W. Webb), Malaise trap across forest path, 20–28.XI.1992 [2ɗ]; km 25.8 Riv. [= Rivière] Bleue road, 213 m (M.E. Irwin, D.W. Webb), Malaise trap across forest path, 3–5.XI.1992 [1ɗ]; Parc 6, 150 m (L.B. de Larbogne, J. Chazeau, A. et S. Tillier), piège de Malaise [Malaise trap], forêt humide sur alluvions [humid forest on river bank], 5–20.I.1987 [1ɗ]; Parc 7, 170 m (L.B de Larbogne, J. Chazeau), forêt humide sur pente [humid forest on slope], 19.XI–4.XII.1985 [7ɗ, 3Ψ (dissection 909: ɗ, SDG 01008)]; Pic du Grand Kauri, 22°17'S x 166°54'E, 250 m (G. B. Monteith), human dung trap, site 8704, 20–21.XI.2001 [2Ψ QMBA]; Pic du Pin, east base, 22°15'S x 166°49'E, 270 m (G.B. Monteith), human dung trap, site 8680, 20–21.XI.2001 [3ɗ, 4Ψ QMBA]; Pont Germain, 22°06'S x 166°39'E, 160 m (G. B. Monteith), human dung trap, site 8724, 17–19.XI.2001 [2ɗ]; start Pourina track, 22°06'S x 166°38'E, 200 m (G.B. Monteith), human dung trap, site 8726, 17–19.XI.2001 [2ɗ]; trail to Upper Riv. [= Rivière] Bleue, 290 m (D.W. Webb), Malaise trap across forest path, 3–5.XI.1992 [1Ψ], 5–16.XI.1992 [6ɗ, 3Ψ (dissection 903: Ψ, SDG 01003)]; trail to Vallée de Pourina, 850 m (D.W. Webb), Malaise trap across forest path, 19–28.XI.1992 [1ɗ, 2Ψ]. Paratypes deposited in AMNH, AMSA, ANIC, BMNH, BPBM, CASC, CAUC, CNCI, CSCA, DEBU, EMEC, HNHM, INHS, KUEC, MCZC, MHNG, MNHN, MZSP, NHMW, NMSA, QMBA, UCDC, USNM, ZISP, ZMHB, and ZMUC.

Distribution. Found in both the Province Nord and Province Sud. In the north, found only at the low elevations (100 m) near Kaala­Gomén and Pouebo. Considerably more widespread in the south, including the low to middle elevation rainforests of Col d’Amieu, Mont Dore, Mont Dzumac, the Monts des Koghis, Mont Ningua, the Plan des Lacs vicinity, the Yaté vicinity, and the Parc Provincial de la Rivière Bleue.

Figures

FIGURE 1. Evertomyia irwini, sp. nov. ɗ. Habitus, lateral view. Scale bar = 1.0 mm.

FIGURE 3. Head, oblique view, right arista removed for clarity. Scale bar = 0.5 mm. A) Evertomyia albeto, sp. nov. ɗ. B) Evertomyia frankadelia, sp. nov. Ψ. C) Evertomyia helenae, sp. nov. Ψ. D) Evertomyia irwini, sp. nov. Ψ. E) Evertomyia matilei, sp. nov. ɗ. F) Evertomyia webbi, sp. nov. Ψ.

FIGURE 10. Evertomyia irwini, sp. nov. ɗ. Male genitalia. Scale bar = 0.2 mm. A) Aedeagal complex, ventral view. B) Aedeagus, lateral view. C) Paramere, lateral view. D) Epandrial complex, lateral view. D) Surstylus, dorsal view.

FIGURE 11. Evertomyia irwini, sp. nov. Ψ. Female genitalia and egg. Scale bar, A – B = 0.2 mm; C = 0.1 mm. A) Terminalia, lateral view. B) Terminalia, ventral view. C) Egg, micropylar end, lateral view.