Drosophila inversa

Pirani, Gabriela & Amorim, Dalton De Souza, 2016, Going beyond the tip of the Drosophilidae iceberg: New Cladochaeta Coquillett, 1900 (Diptera: Drosophilidae) from Brazil, Zootaxa 4139 (3), pp. 301-344 : 327-334

inversa species group

Cladochaeta atlantica nov. sp.

( Figs. 24 A–F; 25 A–C; 34 A; 35 L)

Diagnosis. General body color ochre, pleuron slightly darker, abdomen slightly lighter than thorax; arista with 4 dorsal and 1 ventral branches, dorsal branch between d-3 and d-4; wing infuscate; phallus with a distinguishable membranous portion and seven long heavily sclerotized ventral projections.

Material examined. Holotype Ƌ: BRAZIL, State of São Paulo, São Luís do Paraitinga , P.E.S.M. Núcleo Sta. Virgínia, 23º 19’24.8”S 45º05’40.1”W, 21.i.2011, Malaise trap, N.W. Perioto and team cols. ( MZUSP). Paratype Ƌ: (Terminalia on vial), BRAZIL, State of São Paulo, Campos do Jordão, Horto Florestal Estadual, 22.xi.2010, Malaise Airton & Marcos cols. ( MZUSP).

Description. Head ( Figs. 24 A–C). Higher than wide. Eyes bare; light ochre. Pedicel ochre, first flagellomere whitish; arista with 4 dorsal and 1 ventral branches, dorsal branch between d-3 and d-4. Frons light ochre, ocellar triangle slightly darker; fronto-orbital setae: anterior reclinate absent; posterior reclinate smaller than proclinate, closer to proclinate than to inner vertical. Face flat, ochre. Gena thin, ochre; proboscis and palpus whitish. Thorax ( Figs. 24 D–E). Ochre, pleuron very slightly darker. Anterior dorsocentral ca. ½ of posterior dorsocentral length. Posterior dorsocentral slightly closer to anterior dorsocentral than to scutoscutellar suture. Acrostichals in 6 even rows. Basal scutellars parallel, apical scutellars convergent, cruciate at tip. Three postpronotal setae, mid one larger than other two. Legs pale yellow. Wing ( Fig. 35 L). Length: 1.26 mm. Wing membrane infuscate. Tip of R2+3 slightly curved towards C. R4+5 and M slightly divergent. Crossvein dm-cu slightly bent medially, perpendicular to CuA1. Wing tip round. Halter whitish. Abdomen ( Fig 24 F). All tergites dark ochre. Male terminalia ( Figs 25 A– C). Epandrium inverted U-shaped, with 6 or more long setae on ventrolateral halves, not in a row; ventral tip of ventrolateral halves gradually tapering, slightly curved inwards; broad squared extension of epandrium underneath cercus. Cercus with slightly acute ventrolateral margin. Phallus with a distinguishable membranous portion, ventral tip curved apically; 7 sinuous sclerotized projections, ventrally connected; M-shaped dorsal bridge, projected apically. Phallapodeme longer than wide, heavily sclerotized, with a posterodorsal projection. Surstylus rounded, not clavate, setae present on lateral surface. Hypandrium Y-shaped, ventral keel present.

Etymology. The species epithet refers to the biome of the type locality, the Atlantic Forest.

Comments. This species is placed in the inversa species group based on the general morphology of male terminalia, but this may be somewhat controversial. Cladochaeta atlantica does not have the diffuse infuscation over the costal edge of wing, one of the features described as diagnostic for the group. Furthermore, features the male terminalia are in some degree shared with the sororia species group Grimaldi & Nguyen, 1999. Species of the s ororia species group, however, have the dm-cu crossvein clouded and the hind femur usually with a comb of stiff setae on the apical half of the ventral surface, features not observed in C. atlantica nov. sp.

Cladochaeta periotoi nov. sp.

( Figs. 26 A–C; 27 A–C; 34 B; 36 A)

Diagnosis. General body color dark ochre, abdomen darker than thorax; wing infuscate; legs pale brown, forefemur with two rows of long posterodorsal setae and three longer posteroventral setae; arista with 3 dorsal and 1 ventral branches; laterally asymmetrical phallus united by a large dorsal bridge, with a membranous portion posteriorly.

Material examined. Holotype Ƌ: (terminalia on vial), BRAZIL, State of São Paulo, Serra do Japi, 18.iii.2010, Malaise trap, 667m, N.W. Perioto and team coll. ( MZUSP). Paratype Ƌ (terminalia on vial), same label data as holotype.

Description. Head ( Figs. 26 A–B). Higher than wide. Eyes bare, red. Pedicel light ochre, first flagellomere whitish; arista with 3 dorsal and 1 ventral branches; d-1 and d-2 close to each other, closer to base of arista than to d-3; three minute dorsal branches between d-3 and apical fork; ventral branch midway between d-3 and apical fork; long apical fork. Frons brown, slightly darker on posterodorsal half; ocellar triangle dark brown. Fronto-orbital setae: anterior reclinate small, almost indistinguishable from fronto-orbital setulae, lateroposterior to proclinate fronto-orbital in position; posterior reclinate, as long as proclinate, midway between proclinate and inner vertical. Face flat, pale brown. Gena brown, a lighter area beneath eye, bearing six long setae not in a row, plus vibrissa. Proboscis and palpus pale brown; palpus with two apical setae. Thorax ( Fig. 26 C). Entirely dark ochre. Anterior dorsocentral ca. ½ length of posterior dorsocentral. Posterior dorsocentral midway between scutoscutellar suture and anterior dorsocentral. Acrostichals in eight uneven rows; only two median rows of achrosticals reach posterior portion of scutum. Basal scutellars curved, parallel; apical scutellars convergent. Three large postpronotal setae, mid one longer than other two. Legs uniformly pale brown; forefemur with two rows of long posterodorsal setae and three longer posteroventral setae. Wing ( Fig. 36 A). Length: 1.26 mm. Infuscate membrane, without clouds of infuscation. R2+3 very slightly turned towards anterior wing margin. R4+5 and M parallel, tips slightly convergent. Crossvein dm-cu sinuous, perpendicular to CuA1. Wing tip slightly acute. Halter greyish. Abdomen. Tergites brown. Male terminalia ( Figs. 27 A–C). Epandrium inverted U-shaped, slightly higher than wide, with a row of 7–8 long setae on ventrolateral halves; ventrolateral halves with a slighty broader extension near cercus. Cercus without ventral lobes, ventrolateral edges rounded. Phallus: membranous portion placed between two sclerotized laterally assymetrical structures and phallapodeme. Sclerotized portions flattened laterally, united by a broad bridge on dorsal half, slightly curved inwards. Phallapodeme higher than wide, heavily sclerotized, with a long oblique projection backwards. Surstylus not heavily sclerotized, simple, clavate, with numerous relatively long setae of similar length. Hypandrium y-shaped, ventral portion rounded; strongly sclerotized ventral keel.

Etymology. This species is named after Dr. Nelson Wanderley Perioto, who made a great sampling effort with his team to collect much of the material studied in this paper—eight of the species described here were collected by him.

Comments. This species fits in the inversa species group based on the general morphology of male terminalia (see comments under C. atlantica nov. sp., on issues in the inversa and sororia species groups). Like C. atlantica nov. sp., C. periotoi nov. sp. lacks characters of external morphology considered as diagnostic for both of these groups.

Cladochaeta phallotrixa nov. sp. ( Figs. 28 A–F; 29 A–D; 34 C; 36 B)

Diagnosis. General body color brown, abdomen darker; legs brown. Arista with 4 dorsal and 1 ventral branches, plus apical fork; ventral branch between d-3 and d-4, closer to d-3 than to d-4, at least 4 minute branches on dorsal surface of arista; phallus with poorly sclerotized area between two more sclerotized portions and the phallapodeme, sinuous dorsal bridge uniting both these projections.

Material examined. Holotype Ƌ: (Left wing and head slide-mounted, terminalia on vial), BRAZIL, State of Ceará, Guaramiranga, 4º16’13”S 38º 54’21”W, 880m, 10.v.2014, Malaise trap, Almeida, Lucena & Tavares cols. ( RPSP).

Description. Head ( Figs. 28 A–C). As high as wide. Eyes bare, red. Pedicel light brown, first flagellomere grayish; arista with 4 dorsal and 1 ventral branches, plus apical fork; ventral branch between d-3 and d-4, closer to d-3 than to d-4; at least 4 minute branches on dorsal surface of arista. Frons ochre, ocellar triangle and frontoorbital plate slightly darker; fronto-orbital setae: anterior reclinate small, but easily distinguishable, postero-lateral in position to proclinate fronto-orbital; posterior reclinate as long as proclinate, midway between proclinate and inner vertical. Face flat, dorsal half ochre, ventral half light brown. Gena light brown; proboscis and palpus pale brown. Thorax. ( Figs. 28 D–E). Mesonotum brown, pleuron darker. Anterior dorsocentral ca. ½ of posterior dorsocentral length. Posterior dorsocentral midway between anterior dorsocentral and scutoscutellar suture. Acrostichals in 6 somewhat even rows. Basal scutellars slightly divergent; apical scutellars convergent but not crusciate at tip. Postpronotal lobe with 3 large postpronotal setae, median longer than others. Legs brown. Wing ( Fig. 36 B). Length: 1.4 mm. Wing membrane entirely infuscate. Tip of R2+3 straight, not curved towards C. R4+5 and M parallel. Crossvein dm-cu straight, perpendicular to CuA1. Wing tip slightly acute. Halter light brown. Abdomen ( Fig. 28 F). All tergites brown, posterior margins darker. Male terminalia ( Figs.29 A–D). Epandrium inverted U-shaped, with 6 long setae on ventrolateral halves; ventral tip of ventrolateral halves gradually tapering; terminal portion slightly curved inwards, broader extension near cercus. Cercus with rounded ventrolateral margin. Phallus with poorly sclerotized portion lying between two other more sclerotized portions and the phallapodeme, sinuous dorsal bridge uniting the two projections. Phallapodeme higher than wide, heavily sclerotized. Surstylus sinuous, with setae on entire dorsal and dorsolateral surface. Hypandrium Y-shaped, ventral keel present.

Etymology. The species epithet comes from the Greek roots phallos (for penis) and trixos (threefold), in reference to the three distal sclerotized projections of phallus.

Comments. This species is provisionally placed in the inversa species group based on the general morphology of phallus (see comments under the description of C. atlantica nov. sp. and C. periotoi nov. sp.). C. phallotrixa nov. sp., however, has an entirely hyaline wing membrane and head setulae of usual length, which is not consistent with the diagnosis given to the group.

Figures

FIGURE 24. Cladochaeta atlantica nov. sp., paratype. A. Head, dorsal view. B. Head, lateral view. C. Head, frontal view. D. Thorax, lateral view. E. Thorax, dorsal view. F. Abdomen, dorsal view. Scale bars: 0.1 mm.

FIGURE 25. Cladochaeta atlantica nov. sp., paratype, male terminalia. A. Terminal view. B. Lateral view. C. Lateral view of the complex of aedeagus and paraphyses.

FIGURE 26. Cladochaeta periotoi, nov. sp., holotype. A. Head, dorsal view. B. Head, lateral view. C. Thorax, dorsal view. Scale bars: 0.1 mm.

FIGURE 27. Cladochaeta periotoi, nov. sp., holotype, male terminalia. A. Terminal view. B. Terminal oblique view. C. Lateral view.

FIGURE 28. Cladochaeta phallotrixa, sp. nov. sp., holotype. A. Head, dorsal view. B. Head, lateral view. C. Head, frontal view. D. Thorax, lateral view. E. Thorax, dorsal view. F. Abdomen, dorsal view. Scale bars: 0.1 mm.

FIGURE 29. Cladochaeta phallotrixa, sp. nov. sp., holotype, male terminalia. A, C. Terminal view. B, D. Terminal oblique view.

FIGURE 35. Wings of Cladochaeta species. A. C. armata. B. C. armatopsis nov. sp. (holotype). C. C. balbiae nov. sp. (holotype). D. C. paraitinga nov. sp. (holotype). E. C. bomplandi. F. C. arthrostyla. G. C. asapha nov. sp. (holotype). H. C. chauliodactyla nov. sp. (holotype). I. C. conicophallus nov. sp. (holotype). J. C. dicrophallus nov. sp. (holotype). K. C. grimaldii nov. sp. (holotype). L. C. atlantica nov. sp. (holotype). Scale bars: 0.5 mm.

FIGURE 36. Wings of Cladochaeta species. A. C. periotoi nov. sp. (holoype). B. C. phallotrixa nov. sp. (holotype). C. C. stigmata nov. sp. (holotype). Scale bar: 0.5 mm.