Catasticta sibyllae Nakahara, Padrón & MacDonald, 2018

Nakahara, Shinichi, Macdonald, John R., Delgado, Francisco & Padrón, Pablo Sebastián, 2018, Discovery of a rare and striking new pierid butterfly from Panama (Lepidoptera: Pieridae), Zootaxa 4527 (2), pp. 281-291 : 283-287

Catasticta sibyllae Nakahara, Padrón & MacDonald , new species

( Figs 2–6 )

Diagnosis. Catasticta sibyllae n. sp. is easily distinguished from all Catasticta species by the median area of both surfaces of forewing and hindwing being entirely black with no markings. Catasticta sibyllae n. sp. is readily distinguished from its sister species, C. lisa , by the lack of broad white median band on both sides of dorsal forewing and hindwing. Catasticta sibyllae n. sp. is further distinguished from C. lisa by its rather prominent submarginal and marginal spots on both sides of dorsal forewing and hindwing. Also, these spots on the ventral surface appear more whitish in C. sibyllae n. sp., whereas more yellowish in C. lisa . The genitalia appear not to be informative in this group, thus diagnostic genitalic characters are not provided here.

Description. MALE: Forewing length, holotype: 30 mm; paratype: 33 mm.

Head ( Figs 5a, b ): Eyes naked, with white scales at base; frons covered with brown scales, adorned with black long hair-like scales and white long hair-like scales, area around antennae base similarly with black long hair-like scales and white long hair-like scales; labial palpi roughly twice as long as eye depth, ventrally with white long hair-like scales and brown long hair-like scales, laterally with black scales with ventral and dorsal margin with white scales; antennae approximately half of forewing length, brown, ventrally scattered with white scales, with ca. 35 anntenomeres (n=1, HT), distal 9–10 anntenomeres composing rather prominent club.

Thorax: Dorsally brown with light coloured long hair-like scales; ventrally brown with light coloured long hair-like scales and brown scales.

Legs: Foreleg black, foretarsus longer than tibia, foretarsus and tibia scattered with whitish scales ventrally, in addition to multiple spines, dorsally stripe of white scales present, tibial spurs absent, femur slightly longer then tibia, ventrally brown, dorsally stripe of white scales present; midleg and hindleg not examined.

Wing venation ( Fig. 4): Base of forewing subcostal vein not swollen; four forewing radius veins present; origin of M 1 not associated with discal cell; base of cubitus not swollen; forewing recurrent vein absent; middle portion of m 2 -m 3 portion reduced; hindwing humeral vein developed.

Wing shape ( Figs 2 , 4): Forewing subtriangular, appearing somewhat elongated with costal margin convex in angular manner and concave outer margin, inner margin rather straight; hindwing rounded, appearing slightly elongated, costal margin curved, angles inwards at base, outer margin curved, inner margin slightly concave near tornus, anal lobe almost straight, slightly round.

Wing pattern ( Fig. 2 ): Dorsal Forewing: ground colour black; white submarginal spots slightly suffused with black scales, present in all cells from R 2 +R 3 to 2A, spot in cell R 2 +R 3 -R 4 elongated, appearing more as costal streak, spot in cell R 4 -R 5 small, similar in appearance, spots in cells from R 4 to Cu 2 subsquared, except for streak-like spot in cell M 2 -M 3, spot in cell Cu 2 -2A appearing somewhat doubled; marginal spots slightly suffused with black scales present in all cells from R 4 to 2A, those in cells from R 4 to Cu 1 teardrop-like with black suffusion visible on basal side, spot in cell Cu 1 -Cu 2 squared, spot in cell Cu 2 -2A smallest, distance between submarginal spots in corresponding cells closer towards posterior end as outer margin traverses towards body; fringe blackish; Dorsal hindwing: ground colour similar to forewing; white submarginal spots slightly suffused with black scales, present in all cells from Sc+R to 2A, spots in cells Cu 1 -Cu 2 and Cu 2 -2A smaller, in particular, spot in cell Cu 2 -2A appearing as white hint; marginal spots present in all cells from Sc-R 1 to 2A, spot in Sc+R 1 -Rs elongated and streak-like, spots in cells Rs-M 1, M 1 -M 2 and M 2 -M 3 rather trapezoidal, spots in cells M 3 -Cu 1, Cu 1 -Cu 2 and Cu 2 -2A rather rectangular; fringe black; Ventral forewing: ground colour and general wing pattern similar to dorsal forewing except as follows: ground colour slightly paler; marginal whitish spots appearing larger; submarginal whitish spots appearing larger and more pointier towards base, submarginal spot in cell Cu 2 -2A appearing as two spots; Ventral hindwing: ground colour and general wing pattern similar to dorsal hindwing except as follows: ground colour slightly paler; yellow costal streak at base of costal cell, just distal of humeral vein; reddish patch just basal of humeral vein above subcostal vein; yellow patch at base of discal cell; reddish patch at base of anal cell; submarginal spots smaller and slightly yellow; marginal spots somewhat creamy, additional spot present in cell 2A- 3A.

Abdomen ( Fig. 5c ): Dorsally and laterally black, ventrally with brown scales, white scales and white long hair-like scales, extending along ventral margin of valva; eighth sternite appearing as small plate.

Genitalia ( Fig. 3 ): Tegumen somewhat trapezoidal in lateral view; uncus shorter than tegumen in lateral view with convexed ventral margin, ending in a blunt point, with tuft of hair-like setae visible at base; ventral surface of anal tube weakly sclerotized (this structure is referred to as “gnathos” in Radford & Willmott (2013)); combination of ventral arms of tegumen and dorsal arms of saccus rather straight, middle portion broadens in lateral view; appendices angulares apparently absent; saccus short, broad and straight, similar to uncus in length; juxta appearing as tall plate in posterior view, narrow long stripe in lateral view; valva round, overall appearing somewhat as bean-shaped in lateral view, anterior margin rounded and positioned above uncus, ventral margin curved with hair-like setae present along margin, dorsal margin basal of costa concave, costa pointy, terminating in blunt end; phallus curved, phallobase about one-fourth of phallus in length with trapezoidal winglet ventrally, ductus ejaculatorius visible, manica covering more than half of aedeagus, vesica not examined as phallus not separated.

FEMALE: Unknown or unrecognized.

Types. Holotype: Male with following labels written verbatim: PANAMÁ: Veraguas Prov. Santa Fe 800m 13- IX-1981 Gordon B. Small // Genitalic vial SN-17-177 S. Nakahara // USNM ENT 00804432 //FOTO// (USNM).

Paratype: Male with following labels written verbatim: PANAMA: Bocas del Toro; vic. Fortuna Cabins ; ca. 910m N 08° 46' 40.86" W 082° 11' 2502" May 17, 2018 John R. MacDonald // DNA voucher LEP-68704// ( MEM).

Etymology. The specific epithet is in recognition of Maria Sibylla Merian, a European naturalist and entomologist who embarked on a voyage to South America in the late seventeenth century and conducted empirical research focused on butterflies. Her research, in the form of numerous paintings of insects, served as a foundation for the scientific study of insects, now known as “entomology”. This specific epithet is regarded as a latinized feminine noun in the genitive case.

Distribution and habitat ( Fig. 6 ). This species is known to date from two sites situated in western Panama, namely Bosque Reserva Palo Seco, Bocas del Toro (08̊46' 40.86" N 0 82̊11' 25.02" W) and Santa Fé, Veraguas (precise coordinates unavailable, but the town of Santa Fe lies at 08° 29' 59.99" N 81° 03' 60.00" W). Both sites are somewhat on the border of two vegetation types, sub-montane rainforest and montane rainforest, near the continental divide ( Blandin, 2017).

Biology. JM observed the paratype male nectaring on flowers of Sommera donnell-smithii (Rubiaceae) at about 5–6 m off the ground. Lekking behavior, often seen in this genus, was not observed with this individual. The approximate time of collection was 11:00 am. Other butterflies nectaring or perching on this tree were Glutophrissa drusilla (Cramer, [1777]) ( Pieridae ), Enantia albania (Bates, 1864) (Pieridae) , Panthiades ochus (Godman & Salvin, 1887) (Lycaenidae) , Cupathecla cupentus (Stoll, 1781) (Lycaenidae) , Necyria duellona beltiana Hewitson, 1870 (Riodinidae) , Adelpha leucophthalma leucophthalma (Latreille, [1809]) ( Nymphalidae ), Marpesia merops (Doyère, [1840]) ( Nymphalidae ). Other species observed in the vicinity included: Catasticta sisamnus smalli Eitschberger & Racheli, 1998 (Pieridae) , Archonias brassolis approximata (Butler, 1873) (Pieridae) , Thestius epopea (Hewitson, 1870) (Lycaenidae) , Morpho helenor veragua LeMoult & Réal, 1962 (Nymphalidae) , and Oressinoma typhla Doubleday , [1849] ( Nymphalidae ).

Figures

FIGURE 2. Catasticta sibyllae n. sp. holotype male (dorsal on left, ventral on right); paratype male (dorsal on left, ventral on right).

FIGURE 3. Catasticta sibyllae n. sp. male genitalia, dissection based on the holotype (genitalic vial: SN-17-177): a) lateral view of genitalia in situ at posterior end of abdomen; b) genitalia in lateral view; c) lateral view of uncus, with valva removed.

FIGURE 5. Catasticta sibyllae n. sp. morphology, all images based on the holotype: a) head in lateral view; b) anntennal club in dorsal view; d) abdomen in ventral view.

FIGURE 6. Distribution records for Catasticta sibyllae n. sp., Atlantic slope habitat image of Fortuna forest, where the paratype male was found (photo credit: Thomas J. Riley).