Common grass yellow (Eurema hecabe)

Common grass yellow (Eurema hecabe) is a species of butterfly in the family Pieridae. It exhibits seasonal polyphenism: a darker summer morph is triggered by long daylight hours (exceeding 13 hours), while a brighter post-monsoon morph is triggered by shorter daylight hours (12 hours or less).

The dorsal (upper) surface of the male is yellow, with shades varying—from sulfur yellow to deep lemon yellow—depending on the season and location. On the forewing, the apex (tip) and termen (outer margin) are deep black; this black border narrows as it extends along the costal margin (leading edge) toward the base of the wing, where the color often fades.



The inner boundary of this black area (from the leading edge to vein 4) is highly oblique and irregular. Between veins 2 and 4, the inner edge is concave, featuring an outward-curving section between the veins and a tooth-like projection pointing inward at vein 3. Below vein 2, the black area widens abruptly, forming a square-like patch that covers the entire tornus (the corner near the base of the hind margin).

The inner boundary of this widened section varies; in the typical form, it is slightly concave. On the hindwing, the outer margin bears a narrow black band that tapers toward both the anterior and posterior ends. The dorsal margin appears significantly paler than the ground color of the wing.

The yellow portions of the dorsal surface also reflect light brightly within the ultraviolet spectrum (320–400 nm), a phenomenon resulting from the presence of layered nanostructures within the cuticle.

The ventral (underside) surface is yellow—generally a slightly paler shade than the upperside—and is adorned with reddish-brown markings. The forewing features two small spots near the base of the discal cell, along with a kidney-shaped (reniform) spot or ring in the discocellular area (the middle of the wing).

The hindwing bears a slightly curved row of three small spots in the subbasal area (near the base), an irregular ring or thin spot in the discocellular area, followed by a highly irregular, curved, transverse row of spots or dots across the discal area (the middle of the wing)—some or all of which may often appear faint or nearly invisible. On both the forewing and hindwing, the veins that reach the costal (front) and outer margins terminate in small, reddish-brown spots.

The antennae are grayish-yellow with black clubs (tips). The head, thorax, and abdomen are yellow, accented with dark, dusky (fuscous) scales. On the underside, the palpi, thorax, and abdomen are yellowish-white. When viewed from above, a "sex mark" is visible as a thickening along the basal half of the median vein on the forewing.

In the female, the upperside closely resembles that of the male, though it lacks the sex mark. The black areas on both the forewing and hindwing are slightly broader, and the inner edge of the black band along the margin of the hindwing often appears indistinct.

Females also possess a patch of scales on the upperside near the base of the forewing that reflects ultraviolet light. The mechanism producing this coloration is the same as that found in the males, though the intensity of the reflection is less pronounced.

The underside exhibits a base color and pattern of markings similar to those of the male. The antennae, head, thorax, and abdomen are likewise similar in coloration.

TAXON

Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Hexapoda
Class: Insecta
Subclass: Pterygota
Order: Lepidoptera
Superfamily: Papilionoidea
Family: Pieridae
Subfamily: Coliadinae
Tribe: Euremini
Subtribe: Euremina
Genus: Eurema Hübner (1819)
Species: Eurema hecabe Linnaeus (1758)

Subspecies:
E. h. albina Huang, 1994 (Fujian)
E. h. amplexa Butler, 1887 (Christmas Island)
E. h. biformis Butler, 1884 (Ambon, Serang)
E. h. brevicostalis Butler, 1898 (Timor to Kai Island)
E. h. contubernalis (South, Southeast, East Asia)
E. h. diversa Wallace, 1867 (Buru)
E. h. hecabe (Indo-China)
E. h. hobsoni Butler, 1880 (Taiwan)
E. h. kerawara Ribbe, 1898 (Bismarck Archipelago)
E. h. latilimbata Butler, 1886 (Sumatra, Borneo)
E. h. latimargo Hopffer, 1874 (Celebes)
E. h. mandarina de l'Orza, 1869 (Japan)
E. h. maroensis Butler, 1883 (Maroe Island)
E. h. nivaria Fruhstorfer, 1910 (Solomons)
E. h. oeta Fruhstorfer, 1910 (West Irian to Papua)
E. h. phoebus Butler, 1886 (Northern Australia)
E. h. solifera Butler, 1875 (Africa)

SYNONYMS

Eurema hecabe var. kerawara Ribbe (1898)
Eurema hecabe var. magna Ribbe (1898)
Papilio hecabe Linnaeus (1758)
Terias aethiopica Trimen & Bowker (1889)
Terias amplexa Butler (1887)
Terias bewsheri Butler (1879)
Terias biformis Butler (1884)
Terias bisinuata Butler (1876)
Terias brenda ab. alba Dufrane (1945)
Terias brenda ab. maureli Dufrane (1947)
Terias brenda ab. subalba Dufrane (1945)
Terias butleri Trimen & Bowker (1889)
Terias chalcomiaeta Butler (1879)
Terias contubernalis Moore (1886)
Terias dentilimbata Butler (1879)
Terias diversa Wallace (1867)
Terias floricola ab. alba Dufrane (1945)
Terias floricola f. parva Rothschild (1921)
Terias hecabe
Terias hecabe borneensis Fruhstorfer (1910)
Terias hecabe f. napia Stoneham (1957)
Terias hecabe f. neria Stoneham (1957)
Terias hecabe oeta Fruhstorfer (1910)
Terias hecabe senegalensis f. continua Storace (1949)
Terias latilimbata Butler (1886)
Terias mandarina de l'Orza (1869)
Terias maroensis Butler (1883)
Terias orientis Butler (1888)
Terias phoebus Butler (1886)
Terias photophila Butler (1884)
Terias solifera Butler (1875)

VERNACULAR NAME

Afrikaans: Laeveldgeletjie
Australia: Large Grass-yellow
Chinese (simplified): 宽边黄粉蝶
Chinese (traditional): 寬邊黃粉蝶 - 黃蝶 - 荷氏黃蝶
Dutch: Gewoon grasgeeltje
English: Common grass yellow, Large Grass Yellow, Common Grass-yellow, Large Grass-yellow
French: Coliade Hécabé, Piéride citron
Guangdong: 寬邊黃粉蝶
Hong Kong: 寬邊黃粉蝶
Indonesia: Kupu-kupu belerang biasa, Kupu-kupu belerang, kupu-kupu kuning,
Kupu-Kupu rumput biasa
Japanese: キチョウ - ミナミキチョウ
Java: Kupu jene
Korean: 남방노랑나비
Macao: 寬邊黃粉蝶
Marathi: तृण पिलाती
Spanish: Mariposa amarilla Agave
Taiwan: 寬邊黃粉蝶 - 荷氏黃蝶 - 黃蝶
Thai: ผีเสื้อเณรธรรมดา

Aryo Bandoro
Dlium TheDlium
YouTube: https://www.youtube.com/@Dlium