Stigmacoccus garmilleri Foldi

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 : 30-32

Stigmacoccus garmilleri Foldi

( Fig. 12 )

Material studied. PARATYPE: MEXICO, Chiapas, Huitepec, March 1992, on Quercus sp., R. Greenberg ( USNM, 13006): 1/1 crawler, swollen, becoming "cyst-like" (see discussion) missing most legs, + 4 cysts.

(Note: the single specimen is quite sclerotised and swollen, appearing rather cyst-like. It is here considered that it is on the point of moulting to become a cyst – see comments below.

Unmounted material. Not seen.

Mounted material. Length 1.4 mm, width 1.2 mm. Derm mildly sclerotised throughout.

Dorsum. Hair-like setae, mostly about 30–35 ųm long but some very short; distribution unclear; hairs each 20–42 ųm long. Spines mainly 13–33 ųm long, shortest on anterior abdominal segments; totals on each side (dorsum + venter combined): I 1; II 1 or 2; III 5 or 6; IV 5–8; V 9; VI about 17–24; VII about 20–27; and VIII absent; distribution mainly marginal but with some submarginal on IV–VII. Large bollard-like spines, each about 8–10 ųm wide: distributed as in generic description. Pores: (i) simple convex pores, each 2–3 ųm wide: 1 near each eyespot; (ii) small sclerotised pore, each about 2–4 ųm wide, with a central projection: distribution uncertain; (iii) large bilocular pores, each about 12 ųm long and 10 ųm wide: pair submedially on about segment IV or V only; (iv) tubular pores: rather variable in size, large pores (16–25 ųm long, 12–16 wide – about 2x size of small pores) present mainly in a submarginal longitudinal line on head, thorax and abdominal segments I–V; smallest pores (10–12 ųm long, 8–9 ųm wide) in a submedial line. Abdominal spiracles: each atrium about 18 ųm long. Anal area: anal opening about 47 ųm wide; with 2 rings of short, tubercle-like pores, each ring with perhaps 40–45 pores; wide sclerotised, circular area absent but segment perhaps 150 ųm wide. Anal tube complex about 110 ųm long; each ring of pores with about 15 or 16 pores. Eyespots each about 25 ųm wide.

Venter. Hairs and setae similar to those on dorsum but apparently randomly arranged; long hairs anterior to anus not detected; some hair-like setae between antennae and near procoxae up to 36–50 ųm long; anal lobe setae about 290 ųm long. Spines as for dorsum: mainly marginal, none present on VIII. Large bilocular pores present submedially between abdominal segments I and II and II and III only. Large bollard-like spines: 1 associated with each thoracic spiracle. Tubular pores of two distinct sizes: a submarginal band of large pores on abdominal segments I–VII, similar in size to largest on dorsum; more median pores all small, distribution unclear but with some in submedian line on abdomen. Antennae 6 segmented, each about 360 ųm long; scape about 50 ųm long, number of setae unclear; pedicel 80 ųm long, with 5 setae; flagellar segments III–V each 40–62 ųm long, each with 4 or 5 setae; apical segment large, each about 104 ųm long, with about 10 setae, 2 large antennal bristles and 5 small bristles; surface of segment VI lightly reticulated. Clypeolabral shield missing; labium 155 ųm long. Thoracic spiracles: peritreme 10 ųm wide, muscle plate 25 ųm long. Legs: (mostly missing) metathoracic (length ųm): coxa 61; trochanter + femur 175; tibia 210; tarsus 110; claw 28; number of setae on coxae unknown; trochanter as in generic description; femur with possibly 7 or 8 setae; tibia with perhaps 13 setae, most distal seta about 100 ųm long; tibia with some dermal reticulations on distal end; tarsus with 4 setae; claws as in generic description.

Comment. This specimen looks superficially very similar to a small cyst but clearly has all the facies of a crawler. Whether the structures as seen on this specimen would look similar on younger crawlers is not known. Based on the present specimen, however, the crawler of S. garmilleri differs from those of S. asper and S. paranaensis in: (i) the large size of the submarginal tubular pores (about 2x the size of those on the other two species); (ii) the presence of 2 rings of tubercle-like pores around anal opening (1 on other two species), and (iii) the absence of a clear, broad area of sclerotisation around the anus – although this might be due to the changes which appear to be taking place in preparation for becoming a cyst. For further discussion, see end of 1st section below.

Figures

FIGURE 12. 1 st-instar nymph of Stigmacoccus garmilleri Foldi. For letters, see Fig. 11.