Catachlorops (Rhamphidommia) dubius, Henriques, Augusto Loureiro & Krolow, Tiago Kütter, 2009

Henriques, Augusto Loureiro & Krolow, Tiago Kütter, 2009, Description of a new species of Tabanidae (Diptera) from the Amazon region: Catachlorops (Rhamphidommia) dubius sp. nov. and a key to species of the subgenus, Zootaxa 2295, pp. 64-68 : 65-68

Catachlorops (Rhamphidommia) dubius new species

( Figs. 1 A–D)

Diagnosis. Frontal callus ridge-like, extending three-quarters length of frons; first flagellomere with a small hook-like projection, never reaching the second flagellomere; thorax blackish-brown, with black hairs; scutellum mostly whitish pruinosity and black and white hairs; wing with a transversal dark band, without patches on br, bm and r4 cells.

Description. Female ( Fig. 1 A). Body length (without antenna) 8.0–10.6mm, frontal index 5.0–5.8, divergence index 1.0–1.2. Head ( Fig. 1 B). Eye bare, greenish. Frons parallel-sided, narrow, with whitishbrown pruinosity. Frontal callus blackish, clavate, touching or not the lower inner margin of the compound eyes and extending until the superior third or fourth of the frons. Ocelli vestigial, vertex with small depression. Subcallus with white pruinosity, except in the median suture and in superior border, shiningsmooth, seems a continuation of the frontal callus to subcallus (character shared with C. (R.) potator ). Gena, parafacial and face with pruinosity concolor to subcallus. Parafacial with sparse and short brown hairs. Gena with dense and long white hairs. Face bare, except for a few brown hairs. Antenna variable ( Figs. 1 C–D), with intermediate forms. Scape and pedicel brown-orange, covered with strong black hairs. First flagellomere dark orange with hook-like projection small and never reaching the apex of the first flagellomere. Stylus with length sub-equal to the first flagellomere, dark orange with a tendency to browning toward apex. Palpus slender and elongated with dark brown pruinosity, first segment with pilosity similar to gena, while the second segment has two layers of hair, one with a strong black hair and another with slender white hair. Proboscis with theca membranous and labellum predominantly membranous. Thorax. Scutum (dorsal view) blackishbrown, covered with black hairs, except near the head and lateral margin, whitish. Postpronotal lobe and postalar callus with whitish pruinosity. In lateral view the notopleuron has dark brown pruinosity, with black hairs and some white hairs. Post-alar callus (lateral view) with white pruinosity and mixed white and black hairs. Scutellum bicolored (dorsal view), anterior region with light brown pruinosity and black hairs, the posterior region with whitish pruinosity and black and white hairs. Pleuron with white pilosity and pruinosity. Legs slender, coxae with pruinosity and pilosity concolorous with pleuron. Trochanters and femora dark brown with black and white hairs. Fore and mid tibiae with white pilosity and pruinosity in 2/3 proximal, and black at distal third. Hind tibia with proximal 1/3 with white pruinosity and white and black hairs, 2/3 distal with dark brown pruinosity and black and white hairs. Tarsomeres with pilosity and pruinosity black. Wing mostly hyaline, costal cell and posterior cubital cell brown and with an irregular transverse dark band starting at pterostigma and extending beyond to the vein CuA1. Dark brown veins. No appendix at fork of R4 +5. Abdomen. Tergites dark brown with black hairs; tergite 2 with narrow transverse band posterior with white pruinosity; tergite 3 with transverse band posterior with pruinosity and white hairs, wider in the middle; tergite 4 with medial triangle posterior with pruinosity and white hairs; tergites 5–6 with transverse band posterior with pruinosity and white hairs, tergite 7 with grayish pruinosity, anterior hairs black, posterior hairs white. Lateral margin of tergites with a predominance of white hairs, decreasing toward the apex of the abdomen. Sternites brown with grayish pruinosity and predominantly covered with white hairs. Male. unknown.

Type material. Holotype female: BRASIL, AM [Amazonas], Lábrea, ramal Apaeral, km 09, Sítio São Raimundo, 07°19’10”S; 64°40’07”W, vi.2006. Arm. Malaise, F.F. Xavier F°. Leg. (Dipt. Hol. 512 INPA). Paratypes: same data of holotype (2 Ƥ CAS; 2 Ƥ FSCA; Dipt. 512 P. 1–21 Ƥ INPA; 2 Ƥ MPEG DIP 12006470, DIP 12006471; 2 Ƥ MZSP); BRASIL, AM [Amazonas], Beruri, rio Purus, 03°56’62”S; 61°21’02”W, vii.2003, Malaise, Xavier Leg. (Dipt. 512 P. 22–24 Ƥ INPA); idem, BR 319, Km 350, 05 °12’36”S; 61°30’22”W, floresta úmida, 30.vii – 04.viii.2007, Arm. Malaise, H. Gasca Leg. (Dipt. 512 P. 25–26 Ƥ INPA); idem, Maués, rio Abacaxis, Campina, Pacamiri, 04°35’49”S; 58°13’14”W, na mata, Arm. Malaise, 30–31.v.2008, J.A. Rafael e equipe [Leg.] (Dipt. 512 P. 27–31 Ƥ INPA).

Etymology. Derived from the Latin dubius , which means uncertain. This name was proposed due a difficulty to classify the species in the genera Catachlorops or Dichelacera .

Comments. Catachlorops dubius sp. nov. is readily distinguished from other Rhamphidommia species by characters noted in the key and figures, however we were initially uncertain whether the species belonged to the genus Dichelacera or Catachlorops . In some of our C. dubius sp. nov. specimens the base of the callus is very close or touching the internal margin of the eyes, a pattern characteristic of Dichelacera . According to Fairchild (1969), the genus Catachlorops is separated from Dichelacera by the structure of the frontal callus, which is narrower than the frons, not touching the internal margins of the compound eyes, however intermediate forms do exist. In their review of Dichelacera, Fairchild & Philip (1960: 01) comment that, “The characters used to separate some of these genera seem to us in many cases both trivial and inconstant, as will be indicated below. We do not at present have sufficient material to propose a complete revision of this group, but for our present purposes we consider Dichelacera as including Rhamphis End., Lanemyia Barr. , Acanthocerella Brèthes , Linapha End., Neorhamphis Kröb. , and Macropalpigera Kröb. as synonyms. We also suggest that Catachlorops Lutz , Amphichlorops Lutz , Orthostyloceras Lutz and Psalidia End. are better treated as subgenera of the genus Dichelacera ”. Later, Fairchild (1969: 210) comments that “furthermore the type species of Catachlorops and Amphichlorops differ hardly at all in structure. Six subgenera are here recognized, based chiefly on color characters, especially wing patterns. A number of species do not fit easily into these categories, and others could be placed with equal justification in either of two or more subgenera. Future work may show some or all these subgenera to be unnecessary”.

This debate exposes the need for a large-scale revision of these two genera with the goal of proposing more clear and consistent limits between them. We adopt Fairchild’s (1969) classification and include the new species described here in the subgenus Rhamphidommia , based on the structure of the antenna, predominantly membranous labella, transverse band on the wing, and clear triangles on the tergites.

Additional material examined. Catachlorops lanei —“M5” “HOLOTIPO” “6.9.945 / Est. S. Paulo / Serra do Mar / Cabeça da Anta / Barretto col.” “ Catachlorops / lanei / Barretto, 1946 ” (Ƥ MZSP).

Catachlorops muscosus — “ Brasilien / Nova Teutonia / 27° 11’ B, 52° 23’ L / Fritz Plaumann” “eyes (reviewed) / unicolorous / grennish black” “HOMOTYPE / Catachlorops / pictipennis Krob. ” “Comp w Type Ƥ of / C. pictipennis Kröb / Munich 1964 / Close agreement” “Comp. w. Types of / Rh. muscosa End / on loan of Berlin Mus / G.B. Fairchild 1964 / Good agreement in / Structure – see notes” “ Catachlorops / (R.) muscosa End. / det. I.S. Gorayeb 1990” (Ƥ FSCA).

Catachlorops nebulosus —“Guaratuba – Pa- / raná X-XII 920 / Tybiriçá ded.” “N.T 1487 / Ins. O. Cruz / Lotação 2.1.1983 ” “ Dicladocera # / badia Lutz MS” “HOMOTYPE / Catachlorops / nebulosus Krob. ” “Comp. w. Type of / C. nebulosus Krob / on loan of Mus. Halle 1965 / Close agreement” (Ƥ FSCA).

Catachlorops potator —“ BRASIL, PR, Piraquara / Manancial da Serra Mar / Mar, 252946S – 485854W / 1000m, 08–15.xii.2006, / J.A. Rafael, Arm. Malaise” (4 Ƥ INPA); “ BRASIL, PR, Piraquara / Manancial da Serra Mar / 252946S – 485854W / 1000m, 16–17.xii.2006, / J.A. Rafael & G.A.R. Melo / Arm. luminosa (lençol)” (Ƥ INPA); “ BRASIL, RS, São Fco de / Paula, Potreiro Velho, / 09–12.i.1997, Arno A. Lise / Arm. Malaise” (Ƥ INPA); “ BRASIL, RS, São Fco de / Paula, Potreiro Velho, / 06.i.1999, Arno A. Lise / Arm. Malaise” (Ƥ INPA); “ BRASIL, RJ, Nova / Friburgo, Macaé de Cima, / 22°22’30’’S – 42°29’45’’W ” “ 02.i.2008, 1.400 mts / P.C. Grossi col. / Armadilha luminosa” (2 Ƥ INPA).