Semomesia croesus lacrimosa Stichel, 1915

Nielsen, Gregory J. & Kaminski, Lucas A., 2018, Immature stages of the Rubiaceae-feeding metalmark butterflies (Lepidoptera: Riodinidae), and a new function for the tentacle nectary organs, Zootaxa 4524 (1), pp. 1-32 : 22-23

Semomesia croesus lacrimosa Stichel, 1915

Natural history. Females were occasional visitors to the study area during the rainy season with seven sightings in four years, all between the months of April and November. Males were never observed but females were seen ovipositing twice in the forest. The females landed on a stem in the middle area of the plant and in a head down position placed an egg near the notch of two stems or near a stem on a shoot. A second instar was also found and raised on a Psychotria caerulea in the greenhouse. The first and second instar fed on the adaxial side of the leaf and left the upper epidermis intact. Third instar still fed on the adaxial side of the leaf but at the leaf tip and margins. Fourth and fifth instars fed on the upper surface of the leaf and the dorsal coloration matched the leaf. During the 2 days of the prepupa phase the larva left the host plant and wandered before pupating near the cage floor. Total larval development time was 17 days. Females were observed in the field ovipositing on two species: Ps. caerulea and Pa. gracilenta .

Egg ( Figs. 125–126 ). Embryonic development 6 days (n = 1). Height 0.38 mm; diameter 0.60 mm (n = 2). Newly laid egg dark plum turning lighter golden with darks streaks of the embryo showing through. Exochorion spherical with a flat bottom and about 8 rows of hexagonal cells from the base to the micropylar area.

First instar ( Fig. 127 ). Duration 3 days (n = 1). Head capsule width 0.23 mm (n = 1). Length at eclosion 1.2; maximum length 2.0 mm. Head light tan with clear stemmata, body pale cream color with whitish lateral lobes. Tegument with pairs of dark long setae dorsally and white laterally.

Second instar ( Fig. 128 ). Duration 3 days (n = 1). Head capsule width 0.43 mm (n = 1). Newly molted length 2 mm, maximum length 3.8 mm. Head tan colored. Body medium green dorsally with lateral lobes, prothorax and last abdominal segments a translucent yellow cream color. Pairs of faint white spots distributed along the subdorsal areas, TNOs whitish.

Third instar ( Fig. 129 ). Duration 3 days (n = 1). Head capsule width 0.80 mm (n = 1). Newly molted length 4 mm, maximum length 7 mm. Head tan colored. Body medium grey-green countershaded dorsally with a lighter green lateral stripe and the lateral lobes lighter yet. Tegument covered by tiny white setae irregularly distributed on the thorax and abdominal surfaces. Larger, variable sized dark reddish-brown setae were present dorsally. Lateral lobe setae long, numerous, white and overlap extending to the substrate to form a barrier protecting the venter of the caterpillar. The TNOs are externally evident on segment A8.

Fourth instar ( Fig. 130 ). Duration 3 days (n = 1). Head capsule width 1.1 mm (n = 1). Maximum length 11 mm. Head capsule medium green. Body countershaded green, darker on the dorsal and lighter on the lateral area matching the adaxial leaf coloration where the larvae now feed. The dark sclerotized dorsal setae number around 20 on each segment and are of varying sizes. Very small white setae are present on each segment. Spiracles are white, enlarged on A8 segment. Lateral lobes now reduced, the caterpillar appeared more cylindrical. Dorsal color medium green

Fifth (last) instar ( Figs. 131–133 ). Duration 5 days (n = 1). Head capsule width 1.7 mm, translucent green. Maximum length 18 mm. Morphology and coloration similar to previous instar. After feeding for three days, body colors changed to light green with white spots on the dorsal and lateral areas along with a wide reddish-brown dorsal stripe on the abdomen and a narrower lateral stripe. There was some darkening of the dorsal thoracic segments and A1. The ventral area of A1 to A6 from the lateral lobes to the prolegs turned red.

Pupa ( Figs. 134–135 ). Duration 15 days (n = 1). Maximum length 11.7 mm (n = 1), width 3.8 mm at A2. Base colors are opaque mottled shades of brown and black with a solid black accent on the anterior slope of A2 segment, two conspicuous dark black spots on T3. The wing pads and ventral facing surface of the head from the antennae down also black. The dorsal surface of A10 is reddish brown. The dorsal abdominal segments are populated with light colored posteriorly pointing setae. Clusters of longer whitish setae are present on the A2 crest and bilateral clusters on T1 and T2. Eyes are setose.

Figures

FIGURES 125–135. Immature stages of Semomesia croesus lacrimosa. 125, egg day 1; 126, egg day 4; 127, first instar premoult; 128, second instar; 129, third instar; 130, dorsal view of abdominal setae in the fourth instar; 131, fifth (last) instar; 132, prepupa in dorsal view; 133, prepupa in ventral view; 134, pupa in dorsal view; 135, pupa in lateral view.