Euchromius galapagosalis Capps, 1966

Landry, Bernard & Léger, Théo, 2024, Taxonomic revision of the Crambinae (Lepidoptera, Pyralidae sensu lato) of the Galápagos Islands, Ecuador, Revue suisse de Zoologie 131 (2), pp. 357-387 : 363

Euchromius galapagosalis Capps, 1966

Figs 7, 8 , 42, 43 , 55

Euchromius galapagosalis Capps, 1966: 5-6 , figs 2, 6, pl. 1 fig. 1. Type locality: Ecuador, Galápagos Islands, South Seymour Island .

Euchrombius [sic] ocelleus (Haworth): Lindsey & Usinger, 1966: 163. Misidentification.

Material examined: 27 ♂, 38 ♀ from Ecuador, Galápagos. – Baltra : arid zone; S 00° 28.034’, W 90° 15.231’, 57 m elev[ation].; without precise locality . – Española : Bahía Manzanillo; Las Tunas Trail , 100 m elev.; Punta Suarez . – Floreana : Punta Cormoran; Las Cuevas . – Genovesa : Bahía Darwin . – Isabela : V[olcan]. Darwin , 300 m elev . – Marchena : no precise locality . – Pinta : Plaja Ibbeston [sic]; Cabo Ibbetson , N 00° 32.819’, W90° 44.229’, 8 m elev.; ± 15 m elev.; ± 50 m elev.; arid zone . – Pinzón : plaja [sic] Escondida . – Rábida : Tourist Trail . – San Cristóbal: P[uer]to Baquarizo [sic]; near Loberia , GPS: elev. 14 m, S 00° 55.149’, W 89° 36.897’ ; 4 km SE Pto Baquarizo ; 1 km S El Progreso ; transition zone, SW El Progreso , GPS: elev. 75 m, S 00° 56.359’, W 89° 32.906’; base of Cerro Pelado ; pampa zone . – Santa Cruz: Bahía Conway ; C[harles]D[arwin]R[esearch]S[tation], arid zone; Barranco, arid zone; Academy Bay; Finca Vilema , 2 km W Bella Vista ; casa [house of] L. Roque-Albelo & V. Cruz[-Bedon], GPS: 137 m elev., S 00° 42.595’, W 090° 19.196’; Finca S. Devine; low agriculture zone, GPS: S00° 42.132’, W 90° 19.156’ ; Indefatigable Is [land]., without precise locality . – Santa Fé: Tourist Trail . – Santiago: Bahía Espumilla ; La Bomba ; GPS: 6 m elev., S 00°11.151’, W 90°42.052’; Cerro Inn . – Seymour Norte: arid zone; GPS: 13 m elev., S 00° 24.013’, W 90° 17.422’; without precise locality. Deposited in CAS, CDRS, CNC, MHNG .

Diagnosis: Based on the characteristic Euchromius features of the forewing, i.e., the double yellowishorange median fascia and the terminal row of black dots distally abutted by shining silver dots ( Figs 7, 8 ), this species is unmistakable in the Galápagos. It can be separated from the other New World species by the homogeneous basal brown field of the forewing, without or with very little (fuscous) irroration, contrasting with the conspicuously irrorated field between the median fascia and the subterminal line. In male genitalia ( Figs 42, 43 ) it can be best separated from the other two New World species with a broadly enlarged cucullus ( E. ocellea and E. saltalis Capps, 1966 ) by the shape of the phallus and the configuration of the cornuti on the vesica (see Capps, 1966). Capps mentioned the wingspan to vary between 16 and 21 mm. However, our material contains a female specimen with a wingspan of only 13 mm, but no specimens larger than 19 mm in wingspan.

Biology: Unknown except that moths readily come to light and can be found mostly at low elevations in the arid and transition zones, but some have been collected also in the pampa zone, probably above 600 m in elevation.

Distribution: Endemic to the Galápagos Islands, this species has been collected on many of them: Baltra, Española, Floreana, Genovesa, Isabela, Marchena, Pinta, Pinzón, Rábida , San Cristóbal, Santa Cruz, Santa Fé, Santiago, and Seymour Norte.

Remarks: One male specimen dissected has a teratological bifid uncus ( Fig. 43a ).

Figures

Figs 1-8. Specimens of Crambinae from the Galápagos Islands. (1-4) Mesolia christinae sp. nov. (1) Male, Alcedo, NE side, camp arida alta, 200 m elev., ws: 17.0 mm. (2) Holotype. (3) Female, Fernandina, Cabo Douglas, ws: 19.5 mm. (4) Female, Floreana, Punta Cormoran, ws: 20.0 mm. (5) Argyria lacteella (Fab.), male, Santa Cruz, Los Gemelos, ws: 11.5 mm. (6) Diatraea saccharalis (Fab.), female, San Cristóbal, La Toma, ws: 25.5 mm. (7-8) Euchromius galapagosalis Capps. (7) Male, Santa Cruz, Finca S. Devine, ws: 18.5 mm. (8) Female, Floreana, Punta Cormoran, ws: 17.5 mm.

Figs 42, 43. Male genitalia of Galápagos specimens of Euchromius galapagosalis Capps. (42) Specimen from Pinta, MHNG- ENTO-85671. (42a) Genitalia without phallus. (42b) Phallus. (43) Teratological specimen from San Cristóbal, MHNG- ENTO-85672. (43a) Genitalia without phallus. (43b) Phallus.

Figs 51-55. Female genitalia of Galápagos Crambinae. (51, 52) Mesolia christinae sp. nov. (51) paratype, MHNG-ENTO-85537. (52) paratype, MHNG-ENTO-85552. (53) Argyria lacteella (Fab.), specimen from Isabela, MHNG-ENTO-85675. (54) Diatraea saccharalis (Fab.), specimen from San Cristóbal, slide BL 1585. (55) Euchromius galapagosalis Capps, specimen from Española, MHNG-ENTO-86740.