Leptocera cymatonota Buck, 2009

Buck, Matthias & Marshall, Stephen A., 2009, Revision of New World Leptocera Olivier (Diptera, Sphaeroceridae), Zootaxa 2039 (1), pp. 1-139 : 94-97

Leptocera cymatonota Buck , new species

( Figs. 7 , 24 , 211–217 , 226–229 )

Description. A large species but size very variable, body length 2.2–3.3 mm. Coloration brown, with reddish areas on anterior frons and upper face; trochanters and base/apex of tibiae (especially of hind tibia) pale brown. Lower orbital bristle only slightly shorter than upper one, sometimes of equal length. Pubescence of arista long (as long as in L. caenosa , cf. Fig. 6 ), distinctly longer than in Nearctic species of L. fontinalis group. Prosternal membrane with 1–2 setulae on each side of midline. Mesonotum with characteristic pattern of irregular pruinose stripes and spots ( Fig. 7 ): broad longitudinal bands (narrowed posteriorly) running on each side between dorsocentral row and row of enlarged paramedian acrostichals, broad longitudinal bands in supra-alar/intra-alar area, more or less interrupted at level of transverse suture; all four bands broadly joined anteriorly; bristles in non-pruinose areas arising from small pruinose spots; scutellum with pruinose margins, widened around sockets of bristles. Bristles of scutum long; five enlarged acrostichals (two pairs, one unpaired) very long, longest one at least as long as orbital bristles; 1(–2) incomplete median rows of acrostichals between enlarged ones; prescutellar bristles thin but almost as long as lower orbital bristle. Wing greyish-brown hyaline, somewhat infuscated along anterior margin. Knob of halter whitish (paler than in Nearctic species). Fore tarsus with apical three tarsomeres slightly wider in male than in female. Mid tibia with long bristles; bristle above distal dorsal enlarged, about twice as long as longest anteroapical, much longer than corresponding bristle above distal anterodorsal; ventral posteroapical bristle distinctly longer than dorsal one, extending distinctly (sometimes far) beyond socket of ventrobasal metatarsal bristle ( Fig. 24 ). Hind tibia with several fairly long bristles on dorsal surface, preapical bristle longest but not much longer than bristles above it and not as conspicuously exserted as in L. hexadike sp.n.

Male terminalia ( Figs. 211–214 ): Sternite 5 with very long pale, wavy bristles posteriorly, pale posteromedian area wide. Epandrium also with unusually long bristles (compared to Nearctic species). Surstylus with anterior process dark, moderately long, and perfectly round apically; anterior section of surstylus with bare outer ventral lobe and bristled inner ventral lobe, the latter somewhat projecting posteriorly, with numerous evenly spaced bristles of subequal length. Posterior section of surstylus stout, with dorsal (posterior) bristles restricted to basal half; the two enlarged apical bristles strong, subequal. Aedeagal complex as in Figs. 226–229 .

Female terminalia ( Figs. 215–217 ): Tergite 7 with dark, transverse, median stripe. Sternite 7 with densely microtrichose posteromedian tab. Halves of tergite 8 large. Tergite 10 and cerci completely fused, resulting sclerite elongate and emarginate laterally at 1/3. Each cercus with several shorter and one long hair. Sternite 8 characteristic: lateral margins convex, posterior lobes completely rounded, extending distinctly beyond small median lobe. Spermathecae lemon-shaped, with spicules largely restricted to basal half; surface finely striate.

Type material. Holotype ♂ and 53 ♂♂, 30 ♀♀ paratypes (all DEBU): GUATEMALA, Dpto. Quetzaltenango, 8 km SE Zunil, various altitudes: 2,450–2,650 m, 17–19.vi.1993, FIT, J. Ashe & R. Brooks ( DEBU). Other paratypes: 3 ♂♂, 20 ♀♀, same as previous but 19–21.vi.1993. GUATEMALA. Dpto. San Marcos: 60 ♂♂, 15 ♀♀, San Antonio Sacatepéquez, 8,000 ft, 29.ix.1987, M.J. Sharkey ( DEBU). Dpto. Baja Verapaz: 1 ♀, 8 km S Purulhá, 29.v.1991, FIT, H. & A. Howden ( DEBU). Dpto. Zacapa: 2 ♂♂, 4 ♀♀, 3.5 km SE La Unión, 1,500 m, 23–25.vi.1993, FIT, J. Ashe & R. Brooks ( DEBU). MEXICO. Chiapas: 1 ♀, San Cristóbal de las Casas, 17–21.vii.1964, P.J. Spangler ( USNM); 1 ♀, same but 7.vii.1956, D.D. Linsdale ( EMEC); 12 ♂♂, 2 ♀♀, same but 26–28. v.1990, dung traps, B. Gill ( DEBU); 15 ♂♂, 15 ♀♀, same but 2,200 m, 20–27. v.1990, FIT, Howden & Gill ( DEBU); 17 ♂♂, 14 ♀♀, same but 7,087 ft, various dates: 18.v–25.vi.1969, B.V. Peterson ( CNCI); 2 ♀♀, same but 7,200 ft, 1 and 7.vi.1969, W.R.M. Mason ( CNCI); 6 ♀♀, same but 7,000 ft, various dates: 7–26.v.1969, H.J. Teskey ( CNCI); 7 ♂♂, 2 ♀♀, Mt. Tzontehuitz , 12 mi NE San Cristóbal de las Casas, 9,400 ft, 19.v.1969, B.V. Peterson ( CNCI); 1 ♂, 10 mi NE San Cristóbal de las Casas, 7,500 ft, 13.v.1969, H.J. Teskey ( CNCI); 6 ♂♂, 10 ♀♀, 8 mi NE San Cristóbal de las Casas, 7,500 ft, 6 and 15.v.1969, H.J. Teskey ( CNCI); 1 ♀, 3 mi NE San Cristóbal de las Casas, 8.vi.1969, B.V. Peterson ( CNCI); 1 ♂, 1 ♀, 5 mi W San Cristóbal de las Casas, 7,500 ft, 3.v.1969, H.J. Teskey ( CNCI); 1 ♂, 4 mi W San Cristóbal de las Casas, 7,900 ft, 30.viii–1.ix.1973, fungus trap, A. Newton ( DEBU); 1 ♀, “ Chiapas Jct. Hwys. 190-200” [probably mislabelled: this locality lies in Oaxaca at an altitude of ca. 50 m, far below the elevation range of this species], 7.vi.1969, B.V. Peterson ( CNCI).

Etymology. The species name refers to the irregular, “wavy”, pruinose pattern of the mesonotum (Gr. kymatos: wave).

Distribution (Map 4). Mountains of southern Mexico (Chiapas), and Guatemala from 1,500 –2,900 m.

Discussion. The well-defined pruinose mesonotal pattern of this species immediately distinguishes it from other Leptocera . Leptocera hexadike sp.n., the allopatric sister species of L. cymatonota sp.n. shows a less conspicuous pattern with mesoscutal bristles of weakly pruinose areas not arising from pruinose spots. It also clearly differs from the latter by its supernumerary scutellar bristles.

Figures

FIGURES 7–9. Leptocera thoraces: (7) L. cymatonota sp.n. (Guatemala); (8) L. hexadike sp.n. (Costa Rica); (9) L. fulva (Belize). ad sc—additional scutellar bristles.

FIGURES 16–29. Leptocera mid tibiae and basitarsi. Mid tibia, dorsal: (16) L. neocurvinervis (Chile); (17) L. duplicata (Juan Fernández Is.). Apical half of mid tibia and basitarsus, posterior: (18) L. parallelipennis sp.n. (Juan Fernández Is.); (19) L. ellipsipennis (Juan Fernández Is.); (20) L. erythrocera (Honduras); (21) L. sphaerotheca sp.n. (Mexico); (22) L. plax sp.n. (Ecuador); (23) L. tapanti sp.n. (Costa Rica); (24) L. cymatonota sp.n. (Mexico); (25) L. parafinalis (Canada); (26) L. neofinalis sp.n. (Canada); (27) L. kanata sp.n. (Canada); (28) L. fontinalis (France); (29) L. nigra (South Africa). d ad—distal anterodorsal bristle, d d—distal dorsal bristle, d pa—dorsal posteroapical bristle, l ad—lowermost bristle of proximal anterodorsal series, l pd—lowermost bristle of proximal posterodorsal series, mv—midventral bristle, pa v—preapical ventral bristle, vb—ventrobasal bristle of basitarsus, v pa—ventral posteroapical bristle.

FIGURES 211–217. Leptocera cymatonota sp.n. (Guatemala). Male terminalia (phallus and postgonites omitted): (211) lateral; (212) posterior, right cercus omitted; (213) ventral; (214) sternite 5. Female terminalia: (215) dorsal; (216) spermathecae; (217) ventral. i vls, o vls—inner and outer ventral lobes of anterior section of surstylus.

FIGURES 225–229. Postgonites and aedeagal complex of Leptocera cymatonota subgroup. Postgonite of (225) L. hexadike sp.n. (Costa Rica). Aedeagal complex of L. cymatonota sp.n. (Guatemala): (226) posterior; (227) anterior; (228) lateral; (229) dorsal. bcp—basal connection between postgonites, bp—basiphallus, dp—distiphallus, ea—ejaculatory apodeme, pa—phallapodeme, pg—postgonites.

FIGURES 2–6. Leptocera heads and antennae. Heads of (2) L. argentinica sp.n. (Argentina); (3) L. fulva (Costa Rica). Arista and first flagellomeres of (4) L. aequilimbata (Peru); (5) L. neocurvinervis (Chile); (6) L. caenosa (U.S.A.). ad s—additional setulae on orbit, l or—lower orbital bristle, u or—upper orbital bristle.