Metecia cornifrons Snellen, 1879

Navarro, Fernando R., Barrionuevo, M. Jose & Blas, German San, 2015, A revision of the South American genus Metecia Snellen (Lepidoptera, Noctuidae, Noctuinae), Zootaxa 4007 (4), pp. 567-579 : 572-573

Metecia cornifrons Snellen, 1879

Figs 1, 2 , 9, 10 , 15 , 19–23 , 30 , 31, 36 .

Metecia cornifrons Snellen, 1879: 96 , pl. I, figs a–d; Poole, 1989: 655. Holotype: male Argentina, Cordova (sic.) (RMNH).

Euxoa pampeana Köhler, 1945: 87 , fig. 6e. Syntypes: 1 male [ Argentina], La Pampa, Loventuel (IFML); 1 male (MACN); 2 males (ZSM). Examined. New synonymy.

Euxoa pampeana blanchardi Köhler, 1945: 88 . Holotype: female [ Argentina], Córdoba, Los Cocos, iii.1930 (Blanchard) (IFML). Examined.

Pareuxoina pampeana ( Köhler): Köhler, 1961 : 78 (new combination); Köhler, 1967: 314, fig. 197 (checklist, illustration).

Pareuxoina blanchardi ( Köhler): Köhler, 1961 : 78 (rise to species status, new combination); Köhler, 1967: 298, fig. 198 (checklist, holotype illustration)

Pareuxoa pampeana (Köhler) : Poole, 1989: 779 (catalogue, new combination).

Pareuxoa pampeana blanchardi (Köhler) : Poole, 1989: 779 (synonymized with E. pampeana Köhler , new combination).

Diagnosis. Metecia cornifrons can be identified by the following characters: 1) forewing streaks both extending from wing base and reaching apical margin; 2) head frons with central prominent projection of circular/oval cut with raised edge; 3) male genitalia with juxta dorsal margin produced into two long triangular bars connected to anellus sclerotized plates, central sclerotized horn absent; 4) subbasal diverticulum of vesica with left margin covered by numerous small cornuti; and 5) female genitalia with corpus and appendix bursae fused along posterior 2/3 of their length.

Redescription. Male ( Fig. 1 ). Head frons pale brown, with central prominent projection of circular or oval cut and raised edge ( Figs 9, 10 ); labial palpus whitish with reddish traces and long hairlike scales; antennae biserrate.

Prothoracic collar pale brown with dark brown tufts extending to the eyes.

Forewing length 15.1–16.5 mm, dark brown; costa and veins whitish; streaks from base of wing toward terminal area, anterior streak wider on middle of cell, not contiguous with cubitus, posterior streak reaching termen, along Cu vein.

Genitalia ( Fig. 19 ) with apical dorsal projection of uncus absent. Juxta dorsal margin laterally produced into two long triangular bars connected to anellus sclerotized plates, central sclerotized horn absent. Valve 5X longer than wide; ampulla slender, strongly S-shaped, 0.2X as long as valve; clasper vestigial, as a small triangular extension of the basal sclerite; digitus heavily sclerotized medially, apical half inner curved, strongly narrowed, and heavily sclerotized, free from inner surface of valve for most of its length, apex pointed, not reaching valve posterior margin. Vesica ventrally and close to aedeagus with a sclerotized plate anteriorly covered with strong cornuti ( Figs 20, 21 ); basal diverticulum ventral and large; subbasal diverticulum long, 2X as long as wide, left margin covered by numerous small cornuti ( Figs 20, 22, 23 ); apical diverticulum absent.

Female ( Fig. 2 ) as in male except for: forewing length 16.2–17.9 mm and antenna filiform. Genitalia ( Figs 30, 31 ) with posterior apophysis 4X as long as anterior apophysis. Neither ductus nor corpus bursae with diverticulum, sclerotized plate of the corpus bursae absent. Corpus slightly longer than appendix bursae, both fused along posterior 2/3 of their length.

Bionomics and distribution. Adults have been collected from January to April. Distribution restricted to Argentina (Buenos Aires, Chubut, Córdoba, La Pampa, Neuquén, and Río Negro) ( Fig. 36 ).

Remarks. Nye (see Beccaloni et al. 2003) suggested that Metecia cornifrons was probably the senior synonym of Pareuxoina pampeana blanchardi , perhaps because of their external similarity and both were described from the same province in Argentina. Founded on the resemblance of P. pampeana with P. blanchardi and of those with the description and drawings of M. cornifrons , mainly on forewing pattern and frons projection similarities, these species are herein considered as junior synonymies of M. cornifrons .

Material examined. (42 males, 17 females). ARGENTINA: Buenos Aires. Bahía Blanca, 1 female iii.1946 (Köhler) ( IFML). Chubut. Comodoro Rivadavia, 1 male 25.ii.1938 (V. Oort) ( IFML). La Pampa. General Pico, 1 female (Williamson), genitalia slide Nº 2103FN ( IFML). Neuquén. Bajada Marucho, 870m, 1 female 21.iii.1974 (M. Gentili) (IADIZA), 850m, 2 females 24.iii.1981 (M. Gentili) (IADIZA); C. Curá, Carro Quebrado, 780m, 3 males 19.iii.1996 (M. Gentili) (IADIZA); C. Curá, Rincón León, 650m, 13 males 1 female 15.iii.1997 (M. Gentili) (IADIZA); C. Lil, S. Isabel, 900m, 1 male 24.iii.1973 (M. Gentili) (IADIZA); Coloradas–Antenas, 1000m, 18 males 2.iii.1990 (M. y P. Gentili) (IADIZA), 6 males 27.ii.1993 (M. Gentili) (IADIZA); Ea. Llamuco, 1100m, 6 females 18.iii.1974 (M. Gentili) (IADIZA); P. Pinos, Haichol, 1500m, 1 female 20.iii.1974 (M. Gentili) (IADIZA); Piedra del Aguila, 580m, 1 female 2.iv.1972 (M. Gentili) (IADIZA); Planicie Banderita, 410m, 1 female 2.iv.1975 (M. Gentili) (IADIZA); Quilquihue, 750m, 1 female 21.iii.1983 (M. y P. Gentili) (IADIZA). Río Negro. Arroyito, 325m, 1 female 16.iii.1973 (M. Gentili) (IADIZA).

Figures

FIGURE 36. Distribution map of Metecia species. White circles = M. cornifrons, red stars = M. lacustris, yellow triangles = M. hypothetica.

FIGURES 1 – 6. Male and female of Metecia. 1, M. cornifrons, male. 2, M. cornifrons, female. 3, M. lacustris, male. 4, M. lacustris, female. 5, M. hypothetica, male. 6, M. hypothetica, female. Scale lines: 10 mm.

FIGURES 7 – 14. 7 – 8, male antenna. 7, biserrate, doubly bifasciculate (Metecia hypothetica). 8, deeply bipectinate (M. lacustris). 9 – 14, Frons projections. 9, M. cornifrons (lateral view). 10, M. cornifrons (anterolateral view). 11, M. lacustris (lateral view). 12, M. lacustris (anterolateral view). 13, M. hypothetica (lateral view). 14, M. hypothetica (anterolateral view).

FIGURES 15 – 18. 15 – 16, male abdominal segment VIII. 15, Metecia cornifrons. 16, M. lacustris. 17 – 18, M. lacustris male genitalia, uncus (lateral view). 17, uncus apex curved upwards. 18, close up of uncus apex showing dorsal strong small spines.

FIGURES 19 – 29. Male genitalia. 19 – 23, Metecia cornifrons. 19, male genitalia. 20, aedeagus (lateral view). 21, sclerotized plate (close up). 22, subbasal diverticulum left margin (close up). 23, aedeagus (dorsal view). 24 – 26, M. lacustris. 24, male genitalia. 25, aedeagus (lateral view). 26, aedeagus (dorsal view). 27 – 29, M. hypothetica. 27, male genitalia. 28, aedeagus (lateral view). 29, aedeagus (dorsal view).

FIGURES 30 – 35. Female genitalia. 30, Metecia cornifrons (lateral view). 31, M. cornifrons (dorsal view). 32, M. lacustris (lateral view). 33, M. lacustris (dorsal view). 34, M. hypothetica (lateral view). 35, M. hypothetica (dorsal view).