Harmonia dimidiata ( Fabricius, 1781 )

Zhuang, Jiamin, Wei, Xueyuan, Tao, Xunhong, Wang, Xingmin & Chen, Xiaosheng, 2025, Descriptions of immature stages of six aphidophagous Coccinellini (Coleoptera: Coccinellidae) species from China, Zootaxa 5646 (2), pp. 236-254 : 243-245

Harmonia dimidiata ( Fabricius, 1781)

( Figs 1D–F , 6–7 )

Larval descriptions or illustrations of Harmonia dimidiata : Sasaji 1977: 2, Singh & Phaloura 1990: 89, Phaloura & Singh 1991, Poorani 2023: 126.

Fourth instar larva ( Figs 6A–B, 6E , 7 ). Length 6.1–6.8 mm; width 3.0– 3.3 mm. Body elongate, cylindrical and tapered, with parascoli and chalazae, black and yellow color ( Figs 6A–B ). Head: black, tapered. Epicranial stem absent; frontal arms inverted omega-shaped ( Fig. 7A ), do not reach antennae. Three hemispherical stemmata dark, arranged in a triangle, near at the base of antenna ( Fig. 7A ). Antenna with 3 antennomeres; antennomere 3 with preapical setae and sensilla ( Fig. 7B ). Labrum nearly square, bended at two sides, with setae ( Fig. 7C ). Mandible with two apical teeth ( Fig. 7D ). Maxilla with mala trapezoidal, rounded at apex, with two long curved setae and outer margin with thin and short setae in ventral side ( Fig. 7F ). Maxillary palp with three palpomeres ( Fig. 7H ). Labium with spare setae, posterior margin with numerous short setae, labial palpi with three palpomeres ( Figs 7G, 7I ).

Thorax. Pronotum with two black, semi-oval dorsal plates separated by a narrow band; each lateral margin of plates with four black parascoli; about twelve long chalazae and spare short setae in anterior margin of plates; central surface and posterior margin of plates without projection ( Figs 6A–B ). Meso- and metanotum black, and their plates pale ( Figs 6A–B ). Lateral margins of plates each with a long black and a short parascoli, and a black parascoli bearing three branches in each central surface of plates ( Figs 6A–B ). Lateral margins of mesonotum each with a black sentus, without seta ( Figs 6A–B ). A pair of circular spiracles with lamellae at the opening in anterolateral part of mesonotum. Metanotum laterally each with a black sentus ( Figs 6A–B ). Legs black, long, with setae; ventral part with a bristle brush near the tarsal claw, and row of external setae in the tibia; tarsal claw with a square small basal tooth and dense setae around the tooth ( Fig. 7E ).

Abdomen with nine segments ( Fig. 6E ). Segment S1 to S8 with a pair of anterolateral spiracles similar to those of the mesothorax ( Fig. 6E ). Segment S1 yellow, with black stripe in central surface closed S2; dorsal plates with a pair of yellow parascoli, black at the apex, bearing three branches; dorsolateral plates and lateral areas with two pairs of yellow parascoli bearing two branches. Segment S2 yellow, black in central surface, and pale in basal black projections; dorsal plates and lateral areas with two pairs of black parascoli bearing two branches; dorsolateral plates with a pair of yellow parascoli black at the apex ( Figs 6A–B, 6E ). The color and the location of projection of S3 are similar to those of S2, only different in the surface color of lateral areas ( Figs 6A–B, 6E ). Segment S4 yellow in surface of dorsal and dorsolateral plates, and black in surface of lateral areas, with a black band in central part; dorsally and dorsolaterally with two pairs of yellow parascoli bearing two branches; lateral area with black parascoli ( Figs 6A–B, 6E ). Segment S5 and S6 black and pale in basal black projections, with two pairs of black parascoli in dorsal and dorsolateral plates, and a pair of short black parascoli in lateral areas ( Figs 6A–B, 6E ). Segment S7 and S8 black, and pale in basal black projections, with two pairs of black parascoli in dorsal and dorsolateral plates, a pair of black strumae in lateral areas ( Figs 6A–B, 6E ). Segment S9 black with nearly 20 setae ( Figs 6A–B, 6E ).

Pupa ( Figs 6C–D ). Length 5.2–5.9 mm; width 3.3–3.6 mm. Body oval, convex and truncate in the anterior region, brown with black spots. Thorax: pronotum and metanotum with a pair of black spots. Mesonotum with a pair of black spots in lateral margins. Abdomen: seven visible segments. Segment S1 with two black spots; S3 and S4 with a black stripe on each side; S5 and S6 are similar to S3 and S4; S2, S5, S7 brown, without black spot.

Notes. The larval characters of this species were described by Sasaji (1977). Singh & Phaloura (1990) presented a field key to the larvae of four species within the genus Harmonia , including H. dimidiata and pointed out that H. dimidiata can be distinguished from other Harmonia species by the projections of S 5 in dorsal and dorsolateral areas. Additionally, it can be distinguished from H. axyridis by the coloration of S5 ( Celli et al. 2021). Subsequently, Phaloura & Singh (1991) provided a description of the larval chaetotaxy for this species. Yu (2010) included an illustration of the larva for this species; however, no further descriptions regarding its larva were given. Poorani (2023) presented comprehensive illustrations of this species along with brief descriptions of its immature stages.

Figures

FIGURE 1. Life stages of six studied species of the tribe Coccinellini. A–C. Cheilomenes sexmaculata, larva (A), pupa (B) and adult (C). D–F. Harmonia dimidiata, larva (D), pupa (E) and adult (F). G–H. Harmonia sedecimnotata, larva (G) and pupa (H). I–J. Phrynocaria unicolor, larva (I) and pupa (J). K–M. Coelophora biplagiata, larva (K) pupa (L) and adult (M). N–P. Microcaria pupillata, larva (N), pupa (O) and adult (P).

FIGURE 6. The larva and pupa of Harmonia dimidiata. A–B. fourth instar larva, in dorsal (A) and lateral (B) view. C–D. pupa, in dorsal (C) and lateral (D) view. E. nine segments of abdomen of fourth instar larva, lateral view. Scale bars: 1 mm.

FIGURE 7. Main characters of the fourth instar larva of Harmonia dimidiata. A. head, dorsal view. B. antenna. C. labrum. D. mandible. E. tibiotarsus. F. maxilla. G. labium. H. maxillary palp. I. labial palp. Scale bars: 200 µm in A, B, E, F–I; 100 µm in B, D. Black and blue lines: outlines of structures; red dots: boundaries of segmentation of maxillary and labial palpi.