Neodischistus marstoni, Lamas & Yamaguchi, 2010

Lamas, Carlos José Einicker & Yamaguchi, Carolina, 2010, Revision of Neodischistus Painter, 1933 (Diptera, Bombyliidae, Bombyliinae), Zootaxa 2540, pp. 48-58 : 53-56

Neodischistus marstoni sp. nov.

( Figs. 3A–B; 5A–F)

Material Examined. Holotype Male: Brazil, São Paulo, Araçatuba, Córrego Azul , II.1946, Barreto col. (Deposited in MZUSP) . Paratypes: Brazil, SÃO PAULO: Onda Verde , I.1946, 3 females (26.195, 26.196, 26.200), 4 females, F. Lane col. ( MZUSP) ; Araçatuba, Córrego Azul , II.1946, 1 female, Barreto col. ( MZUSP) ; Avanhandava , II.1946, 2 females and 5 males, Barreto col. ( MZUSP) ; Vera Cruz , 1 female (26.174) and 1 male (26.176), Ramalho col. ( MZUSP) . ESPÍRITO SANTO: Baixo Guandu , X.1970, 1 female, P.C. Elias col. ( MZUSP) . MARANHÃO: Imperatriz , 20.II.1962, 3 females and 1 male, F.M. Oliveira col. ( DZUP) . CEARÁ: Limoeiro , VI.1940, 2 females (26.180, 26.181), Shannon & Alves col. ( MZUSP) . GOIÁS: Jataí , I.1955, 1 male, Carrera col. ( MZUSP) . MATO GROSSO: Maracajú , III.1937, 3 males (26.169, 26.170, 26.172), Shannon & Lane col. ( MZUSP) ; Três Lagoas , II.1953, 1 female (26.738), F. Lane col. ( MZUSP) ; [ Ribeirão Cascalheira ] 12 50’S 51 47’W, 25.II.1968, 1 male (B.M. 1968-260), O.W. Richards col. ( BMNH) . MATO GROSSO DO SUL: Porto Murtinho , 19–31. I. 2008, 10 females, S. Nihei & J. Almeida col. ( MZUSP) and 1 female ( BMNH) .

Diagnosis. The females of N. marstoni sp.nov. are easily distinguished from the females of N. collaris by the lack of orange bristles on the occiput and from N. currani by the diminutive and almost apical antennal style. From the males of N. collaris it can be separated by the patches of silvery scales on the face, occiput and abdomen and also by the long lateral apodeme of aedeagus, which surpass the margin of gonocoxite.

Description. Body length: 5.20 – 7.60 mm. Wing length: 4.20 – 6.30 mm. Head. ( Fig. 3A) holoptic, with ommatidia on upper half much larger than below ( Figs. 3A; 5A); frons dark gray-brown pollinose; ocellar tubercle dark brown pollinose, with sparse long dark brown bristles; face dark brown pollinose, smoothly projecting, with patches of silvery scales on each side with light brown hairs; oral margin polished light brown on lower half; gena dark brown with dark brown pile; antenna light brown; scape twice as long as pedicel, with light brown bristles on apical half; pedicel with small dark brown bristles on upper surface; flagellum yellowish-brown twice as long as scape and pedicel together with one flagellomere and a subapical style; proboscis dark brown projecting beyond oral margin by ¾ of its length; palpus short and slender about 1 / 7 of proboscis length, dark brown with dark brown hairs; occiput dark brown pollinose with dark brown bristles and patches of silvery scales on each side of head and a fringe of long spatulate dark brown bristles. Thorax. Mesonotum dark brown pollinose with dark brown hairs and small shining black scales; scutellum dark brown with long dark brown bristles and small shining black scales; post pronotal lobe, with dark brown bristles; notopleuron with strong dark brown bristles, and supra alar callus with dark brown bristles; post alar callus with light brown hairs; pleura light gray-brown pollinose; anepisternum with slender dark brown bristles on upper half entirely covered with dark brown hairs; katepisternum with dark brown hairs and silvery scales on upper half; anepimeron, meron and laterotergite bare; metepisternum with dark brown hairs and silvery scales; haltere dark brown. Legs yellowish-brown pollinose with dark brown silvery scales; coxae light brown with dark brown hairs; femur I and II with yellowish-brown hairs on ventral surface, femur III with strong bristles on apical third of anteroventral surface; tibia light brown with yellowish-brown bristles and apical spurs; tarsus with yellowish-brown bristles; claws light brown with dark brown tip; pulvilli yellowish, 2/3 as long as claws. Wing hyaline ( Fig. 5B); r-m crossvein at basal of discal cell and anal cell open on wing margin by the length of the r-m crossvein; R2+3 and R4 gently curved upward. Abdomen. Dark brown with polished dark brown scales; tergite III–VIII with silvery scales and sparse yellowish to brown hairs on the sides; sternite I–VIII mixed with polished silvery and black scales with dark brown hairs. Terminalia in lateral view ( Fig. 5C) with gonocoxite elongated with rounded apex; aedeagus with wide base and pointed apex; gonostylus robust, with pointed and hook shaped apex; in dorsal view ( Fig. 5D); lateral aedeagal apodeme long, surpassing gonocoxal margins; ejaculatory apodeme long, surpassing gonocoxal limits, aedeagus long, surpassing the apex of posterior process of gonocoxite.

Female. Similar to the male, except for: body length: 3.70 – 7.00; wing length: 4.40 – 6.90 mm. Dichoptic eyes with normal ommatidia ( Fig. 3B); frons dark brown pollinose with polished black scales; anespisternum with silvery scales and light brown hairs; furca W-shaped, lateral arms divergent, with wider apex ( Fig. 5F); spermathecae oval, 1 / 6 spermathecal duct length; spermathecal ducts thin at base and slightly wider apically; sperm pump placed at basal 1 / 4 of spermathecal duct, 2 / 3 of spermathecae in length; sclerotized collars, weakly sclerotized, developed only on apical ends of sperm pumps ( Fig. 5E).

Etymology. Named after Dr. Norman Marston for his contributions to the knowledge of Neotropical Bombyliidae .