Stigmacoccus

Hodgson, Chris, Gamper, Heather, Bogo, Amauri & Watson, Gillian, 2007, A taxonomic review of the Margarodoid genus Stigmacoccus Hempel (Hemiptera: Sternorrhyncha: Coccoidea: Stigmacoccidae), with some details on their biology, Zootaxa 1507, pp. 1-55 : 23-24

Stigmacoccus species B

( Fig. 9 )

Material studied. COLOMBIA, La Victoria, 15.vi.1978, on Psidium guajava, L. Pasada ( USNM): 3/3 cysts of one size only (probably small), in fair to poor condition.

Unmounted material. Not seen.

Mounted material. More or less circular; length 1.8–2.3 mm, width 2.0– 2.25 mm.

Dorsum. Derm covered in dermal spines except medially on anterior abdominal and thoracic segments, and most of head; intersegmental areas within spines obscure; each spine mainly 20–35 ųm long. With a few short, apically rounded, bollard-like spines associated with each abdominal spiracle, each spine as wide as or wider than long; distributed as follows: segment I 9–13; II–V 10–18; VI 4–12; VII 4–6 and VIII 0. Setae: (i) hairs with or without a shallow depression in derm; each 16–28 ųm long: very sparse; (ii) hair-like setae not detected; (iii) minute setae of 2 types: setose setae about 3–4 ųm long, most common on head; more spinose setae up to 10 ųm long, most frequent near spiracles. Pores: (i) bilocular pores, each about 9–10 ųm wide and about 12 ųm long, clearly larger than tubular pore; each in a shallow dermal depression: sparse; and (ii) tubular pores, each 6–7 ųm wide and 11–16 ųm deep; rather sparse but about equally abundant throughout and 3 or 4 times as abundant as bilocular pores. Abdominal spiracles: outer atrium 25–40 ųm long, 23–27 ųm wide, each with 1 or 2 rows of pores at distal end; central atrium 40–58 ųm long, 28–30 ųm wide, inner atrium short, 5–7 ųm long. Anal area: (i) anal opening 75–80 ųm wide, with about 13 small pores around outer margin; (ii) band of tubercle-like pores about 4–5 pores deep, outer diameter of band 130–145 ųm, each tubercle about 3–4 ųm long and 3 ųm wide and (iii) unsclerotised area with 2 or 3 rings of bollard-like spines, each with a rather flat apex; abdominal spiracles VIII lying laterad to (ii), more or less within outer band of bollardlike spines. Anal tube: (a) outer tube about 100–110 ųm long, and (b) finger-like extensions each 100–110 ųm long; pores distribution on anal tube as in generic description.

Venter. Distribution of spines similar to that on dorsum. Pore and setal distribution similar to that on dorsum. Antennae 16–23 ųm wide, each without setae or small pores on derm near margin. Clypeolabral shield pointing posteriorly, each 310–330 ųm long; labium facing more or less anteriorly, about 145–155 ųm long. Thoracic spiracles: peritreme width each 28–35 ųm, with 1–2 rows of moderate-sized pores totalling about 17–19; length of muscle plate 100–110 ųm; each thoracic spiracle surrounded by 40–70 rounded, bollard-like spines (rarely cone-like), each 5–8 ųm wide; each group evenly distributed on both sides of spiracle in an oval elongate group.

Comment. The cysts of this species can be characterised by the following combination of characters: (i) the distribution of the dermal spines, extending onto the prothorax; (ii) the relatively few short, bollard-like spines around each abdominal spiracle; (iii) presence of similar bollard-like spines in an oval elongate group equally abundant on both sides of each thoracic spiracle; (iv) each bilocular pore significantly larger than tubular pores; (v) the structure of the sclerotised anal complex, and (vi) the 1–2 rings of moderate-sized pores within the peritreme of each thoracic spiracle.

Figures

FIGURE 9. Cyst stage of Stigmacoccus species B, from Colombia. For lettering, see Fig. 5.