The immature stages of Oxycarenus gossypinus Distant (Hemiptera, Lygaeidae)
Revue Zoologique Africaine 98(3): 596-605
ISSN/ISBN: 0771-0488 Accession: 006689963
The eggs of O. gossypinus are white and glossy, elongated and oval; the chorion is sculptured with discernible ribs and the egg-case is transparent and also ribbed. Mean length of 30 eggs was 0.88 mm. Mean lengths of the nymphal instars were 1.28; 1.83; 2.39; 3.21 and 3.92 mm; the mean widths of the vertex were 0.25; 0.37; 0.46; 0.60 and 0.70 mm, respectively. The lengths of nymphs and color of nymphal instars 3-5 were used in separating nymphs of O. gossypinus from those of O. hyalipennis. The development of wing pads in nymphal instars 3-5 is another important morphological feature for separating them from nymphal instars 1-2. An overall mean growth ratio of 1.30 was recorded for this species. A regular relationship existed between the measurements of nymphal vertex and the duration of their developmental periods, and a significant correlation coefficient (r = 0.98) was obtained.