Eurema albula marginella

Nieves-Uribe, Sandra, Llorente-Bousquets, Jorge & Flores-Gallardo, Adrián, 2025, Exochorionic morphology in two species of white Eurema (Pieridae: Coliadinae) and its taxonomic contrast on Euremina proposals, Zootaxa 5621 (1), pp. 111-130 : 122-130

Eurema albula marginella

( Fig. 4 C ; Figs. 7–8 A–C ). Chorion of 1171 µm long and 363 wide, 3.2 times longer than its equatorial width ( Fig. 4 C ), and ratio w/l of almost 1/3 (h=14). Color N 00 A 10 M 00. Semifusiform with a convex base and apex ( Fig. 4 C ), the basal region is slightly wider than the apical ( Fig. 4 C ). The micropyle is triangular with curved edges and one micropylar opening at each vertex ( Fig. 7 A ). The micropylar polygon is barely depressed and surrounded by a rosette of three broad rectilinear petals with slightly pointed vertices ( Fig. 7 A ). The petals are anchored to the central polygon, even though their lateral walls are thinner than the external ones ( Fig. 7 A-B). Both petals and wreath lack texture ( Fig. 7 A ). The perimicropylar region shows an irregular wreath of 14 curved-edged foils within a poorly defined semi-ring; some foils have incipient or absent walls and only the external ones can be seen ( Fig. 7 B-i). No transition zone posterior to the wreath ( Fig. 7 B-C), and it continues through the apical polygons with aeropyles at their vertices and an incipient micro-grid ( Fig. 7 C-ii; Fig. 8 A-i), which is more conspicuous towards the equator ( Fig. 7 C ). The aeropyles are semicircular and located singly at the vertices of the polygons ( Fig. 7 C ; Fig. 8 A ). 8–12 aeropyles at the vertices, aligned in an apex-equator direction ( Fig. 7 C ); the micro-grid in this region shows 3–6 very irregular polygons per macro-grid cell and barely conspicuous ( Fig. 8 A ). Towards the equator, 16–18 almost straight axes are recorded in lateral view (31–37 in total) with few fusions and bifurcations ( Fig. 4 C ). 65–72 ribs, mostly straight and some diagonal ( Fig. 4 C ). The axes stand out from the visual plane with great relief ( Fig. 8 B ), with twice the thickness of the ribs and 1.5 times thicker than the micro-grid ( Fig. 8 B ). The macro-grid cells are rectangular and of constant size ( Fig. 4 C , Fig. 8 B ), although narrower towards the base ( Fig. 4 C , Fig. 8 D ). Each macro-grid cell shows between 8 and 11 semi-elliptical micro-grid polygons without texture in their lumen ( Fig. 8 B ). Both grids maintain their thickness from pole to pole, and it fades slightly towards the prebase, where it is only recorded with scarce relief. Basal aeropyles are not recorded ( Fig. 8 C ). In the basal zone, the edges of the polygons and the texture are blurred, so a subtle roughness is recorded ( Fig. 8 C ).

Eurema albula marginella :

Colombia: Putumayo, Mocoa , EBMA , arriba del campamento (01°06’41” N, 76°40’44” W), 842 msnm, 14-IX-2022, A. Luis (ABD-2425), M. Trujano (ABD-2426) ; Ecuador: Puyo, San Ramón, Centro Ecológico Sancha Arajuna , 218 msnm, 19/ 20-VII-2008, Ítalo G. Tapia (ABD-3234); Sucumbíos, Lumbaqui, camino a la Antena , 750 msnm, 22-III-2001, J. Llorente et al. (ABD-2969); 23-III-2001, A. Luis (ABD-2972). No mature exochorion : Ecuador: Puyo, San Ramón, Centro Ecológico Sancha Arajuna , 218 msnm, 19/ 20-VII-2008, Ítalo G. Tapia (ABD-2963, ABD-2970); Sucumbíos, Lumbaqui, camino a la Antena , 750 msnm, 23-III-2001, JA. Luis et al. (ABD-2971); Yasuní , 1-XII-2004 (ABD-3233) .

Figures

FIGURE 4. Chirographs in lateral view of the subspecies of Eurema albula. A. E. a. ceciliana; B. E. a. celata; C. E. a. marginella; D. E. a. sinoe; E. E. a. albula (Detail of its micro-grid on the right).

FIGURE 7. Photographs of the chorion of Eurema albula marginella (A–C) and E. a. sinoe (D–F) under SEM.A–D. Micropyle; B–E. Micropylar region; C–F. Apex. i. Wall absent in wreath foil; ii. Subtle micro-grid in apical polygons; iii. Subtle anchorage in micropylar rosette; iv. Aeropyles of smaller diameter near the equatorial third.

FIGURE 8. Photographs of the chorion of Eurema albula marginella (A–C) and E. a. sinoe (D–F) under SEM.A–D.Aeropyles; B–E. Grids at the equator; C–F. Base. i. Subtle mico-grid in apical polygons; ii. Roughness in micro-grid lumen.