Argyrotaenia loxonephes ( Meyrick, 1937 )

Trematerra, Pasquale & Brown, John W., 2004, Synopsis and descriptions of two new species, Zootaxa 574, pp. 1-12 : 5-6

Argyrotaenia loxonephes ( Meyrick, 1937)

Figs. 5, 6 , 11 , 14

Eulia loxonephes Meyrick, 1937: 128 .

Argyrotaenia loxonephes ; Powell et al., 1995: 147; Razowski and Becker, 2000: 321.

Diagnosis. Argyrotaenia loxonephes can be distinguished by the following characters: forewing length 10–12 mm, with ill defined markings; valva short and broad, with slightly convex costa; vesica with 2 spindle­shaped cornuti; sterigma weakly sclerotized, concave in middle dorsally, with weakly sclerotized anterior edge; and colliculum as broad as ductus bursae, strengthened with an internal sclerite.

Redescription. Male ( Fig. 5 ). Head: Pale brown. Labial palpus pale brown, slightly darker terminally. Antennal scaling pale yellow speckled with brown scales. Thorax: Pale brown. Forewing length 7.3 mm (n = 1), oblong, costa arched near base, otherwise straight, apex obtuse­pointed, termen oblique. Ground color pale cream, transversely strigulated with light brownish; basal and subbasal fasciae obsolete; median fascia oblique, brownish, nearly obsolete, very slender in costal area; marginal line brown, evident in apical 0.3; no other conspicuous markings. Cilia pale cream. Hindwing pale yellowish, strigulated with light grey. Cilia pale cream. Abdomen: Genitalia ( Fig. 11 ) with uncus relatively long, rounded apically; tegumen small; socius small, with weak hairs; gnathos arm slender, terminal plate pointed; vinculum with distal fold sclerotized; valva short and broad, with weakly convex costa; pulvinus indistinct, with weak hairs; sacculus simple, extending to apex of valva, slightly convex in median part, without free termination; transtilla tapering medially; juxta small. Aedeagus long, slender, with pointed termination, caulis small, coecum penis tapered; vesica with 2 spindle­shaped cornuti.

Female ( Fig. 6 ). Head, thorax: Essentially as described for male; forewing length 5.9– 6.1 mm (mean = 6.0; n = 3). Abdomen: Genitalia ( Fig. 14 ) with papillae anales well developed; sterigma cup­shaped, concave in middle dorsally, with weakly sclerotized anterior edge; sterigma large, with distinct microsetae, anteostial portion distinct, weakly sclerotized; colliculum as broad as ductus bursae, strengthened with internal sclerite; ductus bursae moderately long and proximally enlarged; ductus seminalis postmedian; proximal sclerite of ductus bursae absent; corpus bursae subspherical; signum typically archipine, elongate, more than 0.5 length of bursa copulatrix, capitulum well developed.

Lectotype, Ψ, Argentina, Pampa , r.f. Solanaceae, F. Bourquin (BMNH).

Additional specimens examined. ARGENTINA : [no locality data], Jan 1938 (1ɗ, 1Ψ), G. Pico (USNM).

Distribution. Pastrana (in litt.) reported this species from Jujuy, Córdoba, Mendoza, Buenos Aires, La Pampa, Neuquén, Río Negro, and Tucumán in Argentina . Unfortunately, because he did not distinguish it from A. pomililiana or A. tucumana , it is possible that some of his records refer to the latter two species.

Biology. The species was described from two females reared from a species of Solanaceae ( Meyrick 1937) . Bourquin (1938) reported it feeding on the flower heads of Dahlia spp. ( Asteraceae ); descriptions and illustrations of the early stages can be found in that paper. Argyrotaenia loxonephes was observed to be a pest of Linum usitatissimum (Linaceae) at Estactión Experimental Agrícola de Pergamino (Chiarelli de Gáhan 1945). Pastrana (in litt.) recorded it from the following host plants: Humulus lupulus (Canabinaceae) ; Baccharis salicifolia , Dahlia spp., Gutierrezia mondonii (Asteraceae) ; Pelargonium sp. ( Geraniaceae ); Zea mays (Poaceae) ; Gladiolus sp. ( Iridaceae ); Mentha piperita (Lamiaceae) ; Glycine max , Medicago sativa (Fabaceae) ; Asparagus officinalis , Lilium sp. ( Liliaceae ); Linum usitatissimum (Linaceae) ; Eucalyptus spp. ( Myrtaceae ); Plantago spp. ( Plantaginaceae ); Rumex sp. ( Polygonaceae ); Cydonia oblonga , Malus sylvestris , Prunus domestica , Pyrus communis , Rosa spp., Rubus idaeus , Rubus . sp. ( Rosaceae ); Populus nigra var. italica (Salicaceae) ; Ribes grossularia , R. nigrum , R. sativum (Saxifragaceae) ; Apium graveolens (Apiaceae) ; and Vitis vinifera (Vitaceae) . Unfortunately, because Pastrana did not recognize either A. tucumana or A. pomililiana , it is likely that some of the host records presented above refer to the latter two species rather than A. loxonephes .

Remarks. The association of the sexes is not without question ­ the male listed above and illustrated in Figs. 5 and 11 is considerably larger than the female. As in A. tucumana and A. pomililiana , the forewing pattern is not similar between the sexes. The male genitalia of the specimen we assign to A. loxonephes differ from all examples of A. pomililiana (n = 7) and A. tucumana (n = 3) that we examined, particularly in the number and shape of the cornuti. We assign this male to A. loxonephes on the basis of two related pieces of circumstantial evidence: (1) the male and female specimens cited above from USNM share identical collecting data and hence are suspected to be conspecific; and (2) the female of that pair is identical to the lectotype of A. loxonephes .

Figures

FIGURES 1 – 8. Adults of Argyrotaenia species. 1, A. pomililiana (male); 2, A. pomililiana (female); 3, A. tucumana (male); 4, A. tucumana (female); 5, A. loxonephes (male); 6, A. loxonephes (female); 7, A. sphaleropa (male); 8, A. sphaleropa (female).

FIGURES 9 – 12. Male genitalia of Argyrotaenia species; valvae spread and aedeagus removed. 9, A. pomililiana; 10, A. tucumana; 11, A. loxonephes; 12, A. sphaleropa.

FIGURES 13 – 15. Female genitalia of Argyrotaenia species. 13, A. sphaleropa; 14, A. loxonephes; 15, A. tucumana; 16, A. pomililiana.