Annls LimnoL 29 (2) 1993 : 171-174
Redescription of Pseudosmittia bilobulata (Edw.) comb. n.
( = Spaniotoma (Smittia) bilobulata Edwards 1931) and description
of P. neobilobulata sp.n. (Diptera : Chironomidae) from Argentina
A.C.
Paggii
Keywords : Taxonomy, Diptera, Chironomidae, Orthocladiinae, Pseudosmittia, Argentina.
The Holotype of Spaniotoma (Smittia) bilobulata Edwards, 1931 : 299, is redescribed and transferred to the genus
Pseudosmittia (Goetghebuer) Brundin 1956 emended by Saether 1981. Furthermore P. neobilobulata sp.n. is described
and figured. The genus is first recorded in Argentina.
Redescription de Pseudosmittia bilobulata (Edw.) comb. n. ( = Spaniotoma (Smittia) bilobulata Edwards 1931) et des-
cription de P. neobilobulata sp.n. (Diptera : Chironomidae) d'Argentine
Mots clés : taxonomie, Diptera, Chironomidae, Orthocladiinae, Pseudosmittia, Argentine.
L'holotype de Spaniotoma (Smittia) bilobulata Edwards, 1931 : 299, est redécrit et transféré au genre Pseudosmittia
(Goetghebuer) Brundin 1956 emendé par Saether 1981. De plus, P. neobilobulata sp.n. est décrit et dessiné. Le genre
est signalé pour la première fois en Argentine.
While revising adult material from Ramos Mexia
Lake,
Chocon, Province of Neuquen, specimens
very similar with the description of Spaniotoma
(Smittia) bilobulata Edwards (1931 : 299) were exa-
mined. A recent key (Oliver 1981) key the species
out to Pseudosmittia (Goetghebuer) in the sense of
Brundin (1956), posteriorly emended by Saether
(1981).
As result of the study of this specimens, Pseudos-
mittia neobilobula n.sp. is erected. New material col-
lected from Sauce Grande Stream, Province of Bue-
nos Aires let obtain specimens of S. (S.) bilobulata
Edwards which allowed thus, to compare, transfer
and define both species.
The Holotype of Spaniotoma (Smittia) bilobulata
Edw. is from British Museum of Natural History.
London and was prepared into slides. The morpho-
logy terminology follows Saether (1980). Measure-
ments and ratios follow Schlee (1966). The number
of individuals measured are given by parenthesis.
1.
Instituto de Limnologia « Dr. R.A. Ringuelet », C.C.712,
1900 La Plata, Argentina.
Contrib.
Cientif. N° 530.
Pseudosmittia bilobulata (Edwards) n. comb.
Spaniotoma (Smittia) bilobulata Edwards, 1931.
Type material examined : Holotype male, Argen-
tina : Territorio. Rio Negro, Viedma,
23-X-1926,
F.
& M. Edwards (Type nr. : BM 1927-63). Paratypes :
2 males, Ayo. Sauce Grande, Sierra de la Ventana
(alt. : 1.239 m), Buenos Aires, 24-IX-88, Rodrigues
Capitulo col., Instituto de Limnologia de La Plata,
Argentina.
Diagnosis : The species is characterized by an Anten-
nal Ratio of about 0,72 ; normally developed ante-
pronotum, presence of about 4 acrostichals on scu-
tal tubercle ; Venarum Ratio of 1,33, Cul sligthly
curved ; distinct anal point with setae on it, double
inferior vulsella of gonocoxite.
Male imago (n = 1-3) (Holotype apart stated)
Total length 1,90 mm (Hoi.), 2,17-2,25 mm) (2).
Wing length
1,17-1,30
mm (3). Total length/wing
length
1,62-1,80
(3). Coloration brownish black,
pruinose, wings whitish.
Head : Antennae with 13 flagellar segments, A.R.
= about 0,72 (Hoi.). Temporal setae (postorbitals)
Article available at http://www.limnology-journal.org or http://dx.doi.org/10.1051/limn/1993015