Scea erasa Prout Plate, 1918

Miller, James S, 2009, Generic Revision Of The Dioptinae (Lepidoptera: Noctuoidea: Notodontidae) Part 2: Josiini, Bulletin of the American Museum of Natural History 2009 (321), pp. 675-1022 : 847-848

Scea erasa Prout Plate 35

Scea erasa Prout, 1918: 425 .

TYPE LOCALITY: Peru (E), Pozuzo, 5000– 6000 ft.

TYPE: Syntype ♀, leg. ‘‘Native Collector’’ ( BMNH).

DISCUSSION: Scea erasa and S. bryki are the only two described Scea species in which the large FW triangle is completely orange, without black-lined veins (pl. 35). Scea erasa (FW length 5 20.0–21.0 mm) is larger than S. bryki (FW length 5 17.5 mm), but no other pattern characters separate the two. Based on the scant label data available, S. erasa occurs exclusively on the eastern slope of the Peruvian Andes, from Junín north to San Martín. Scea bryki , known solely from the ZMH type, is from Vilcanota, further south. Comparison of genital morphology suggests that S. erasa is a close relative of S. cleonica (pl. 34; fig. 350), from southern Ecuador, but that it is not particularly close to S. bryki .

Other than a single male at the MUSM in Lima (JSM-1720), S. erasa is known exclusively from females—11 at the BMNH (including the type) and three at the ZMH. However, the identity of each of these female specimens needs to be checked. For example, Prout (1918: 425) noted that the BMNH holdings include material he identified as S. erasa , collected by Anton Fassl at Cañon de Tolima (2500 m) in Colombia. My experience with other dioptine taxa suggests that the specimens from Tolima will ultimately prove to be a species distinct from Peruvian S. erasa .

Prout (1918: 425) noted that Scea erasa is a ‘‘beautiful mimic of Darna trigonata Warren [ Arctiidae : Pericopinae ], which occurs with it at Pozuzo and Cushi’’. He further pointed out that Druce misidentified the specimen that later became the S. erasa type, labeling it ‘‘ Darna trigonata Warr. , compared with type’’. This misidentification can perhaps be attributed to the remarkable mimicry that occurs between josiines and the Arctiidae . Alternatively, it could have been due to what Prout (1920: 508) called ‘‘Druce’s deplorable ignorance of systematic entomology’’.

A spectacular undescribed species (pl. 34), superficially similar to S. erasa , has been captured at Machu Picchu, Peru. Its wings (FW length 5 23.0–24.0 mm) are significantly larger than those of S. erasa , and it shows a slightly less extensive and differently shaped, orange FW triangle. The FW radius and cubitus are dusted with blackish scales from the wing base. The genitalia of the two taxa differ dramatically. Slide data for the undescribed taxon are as follows: ³, Peru,

Cuzco, Machu Picchu , Inca Trail, 2500 – 2800 m, 15 Aug 1970, leg. G. A. Gorelick, LACM (genitalia slide no. JSM-1621 ) ; ♀, Peru, Cuzco, Machu Picchu , 9500 ft, 6 Mar 1947, leg. J.C. Pallister, AMNH (genitalia slide no. JSM-1622 ) .

DISTRIBUTION: Peru (BMNH, CUIC, MUSM, ZMH); Colombia (BMNH) .

DISSECTED: ³, Peru, Junín, 1 km S Mina Pichita, 1105 /7525, 2100 m, 21 Aug 2003, leg. J.J. Ramírez, MUSM (genitalia slide no. JSM-1720 ) ; ♀, Peru, Tambo Eneñas to Dos de Mayo, Cam. del Pichis , 5 Jul 1920, Cornell Univ. Expedition, Lot 607, sub 126, CUIC (genitalia slide no. JSM-1721 ) .