Stibaroma melanotoxa Guest, 1887

Young, Catherine J., 2006, Descriptions of the eggs of some southern Australian Geometridae (Lepidoptera), Zootaxa 1287, pp. 1-294 : 1-294

Stibaroma melanotoxa Guest (Figs 384–391)

(type species)

Oviposition

4♀ code nos.: G19, G71, G76, G81

Oviposition period: 6 Apr.–24 May

Batch size range: 20–50 (n = 4)

Realised fecundity (range): 20–50

Note: McFarland (1988) reported 200 eggs from one female

Incubation time (days): 31 (on moistening)

Note: McFarland (1988) reported that moisture was not required for eclosion.

Batch configuration and attachment: Attached, large groups (Fig. 384)

Note: Eggs reared by McFarland (1988) were laid in long rows. However McFarland noted that the species he described was most likely a mixture of S. melanotoxa and an undescribed species thus oviposition behaviour may vary between species.

Colour: Olive green, lustrous, becoming light chocolate brown and coppery brown on maturity (Figs 384 & 385).

Size (mm): (n=13) L = 0.91 ± 0.02, W=0.67 ± 0.02, T=0.56 ± 0.01

Width/length: 0.74

No. of females: 1

Aeropylar opening size (m) (n=5): L=2.66 ± 0.17, W=2.45 ± 0.13

Relative aeropylar opening size: 2.4

Micropyles: Indistinct (Figs 386 & 387)

No. of openings: obscure

No. of cells in rosette: 10

No. of rows of cells in micropylar area: 2

Shape: Moderately broad, bluntly ovoid, anterior pole truncated, flattened dorsoventrally, anterior pole slightly angled to horizontal axis (Figs 384–386 & 388).

Characteristics: Egg marked on all surfaces by generally rounded, concave, hexagonal cells with broad elevated walls forming a mesh­like network over egg (Figs 386, 388, 389 & 391), irregularly shaped in middle of top wide side of egg (Fig. 391). Aeropyles elevated, openings small (Fig. 390) present on narrow lateral sides, posterior pole, perimeter of anterior pole (Fig. 391). Micropyles off­centred (Fig. 386). Chorion smooth, undulating (Fig 390).