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 : 34-35

Stigmacoccus garmilleri Foldi

Material examined. PARATYPE: MEXICO, Huitepec, March 1992, on Quercus sp., R. Greenberg ( MNHN, 13006): 1/1, poorly stained, in early stages of moulting. Note: this specimen was too poor to illustrate but adequate for a description.

Unmounted material. Unknown.

Mounted material. Length 3.5 mm, width 2 mm; poorly sclerotised, rounded at both ends, with small wing-buds on each lateral margin. Antennae 9 segmented; legs fairly well developed, some tibia slightly malformed but not strongly bent; both thoracic and abdominal spiracles without associated loculate pores; hairs and hair-like setae present, frequent; loculate pores frequent over body, mainly with 5 loculi, each usually with 1–5 hairs near margin; tubular pores throughout, probably of two sizes; oval segmented pores possibly absent from posterior abdominal segments.

Dorsum. Derm on head without a reticulate pattern. Setae rather sparse, hair-like setae strong, each about 30–35 ųm long; hairs each 13–25 ųm long; hairs most abundant associated with loculate pores. Derm without large spinose pores. Dermal pores probably as on adult female but many not located: loculate pores: each 12– 14 ųm wide, with mainly 5 loculi: present throughout; each with 1–5 hairs on derm near pore margins; oval segmented pore considered to be absent. Tubular pores present but structure unsclerotised; probably of 2 sizes: present throughout. Anus surrounded by a clear area of derm, without pores or setae; anal tube not located. Eyespots present just posterior to scape, obscure, each about 45–48 wide. Abdominal spiracles (some in process of moulting): outer atrium about 20 ųm long and about 22 ųm wide, presence of pores along inner margin uncertain; central atrium about 22 ųm long and 20 ųm wide; innermost atrium 10 ųm long and 20 ųm wide, with a narrower, sclerotised opening to trachea; total length about 50 ųm; all without a group of associated loculate pores; spiracles on segment VIII about 165 ųm apart.

Venter. Hair-like setae perhaps slightly longer and less spinose than those on dorsum, some up to 95 ųm long; longest and densest medially on posterior abdominal segments. Small, spine-like setae: 1–3 present laterad to each thoracic spiracle, each about 2–4 ųm tall. Pores probably as on dorsum: with no concentration of loculate pores near each thoracic spiracle; oval segmented pores absent. Tubular pores as for dorsum. Antennae 9 segmented, each 1 mm long; scape about 380 ųm long, with many setae but no pores; pedicel narrower, also unsclerotised along proximal margin, about 130 ųm long, with many setae plus at least 2 campaniform sensilla; other segments each about 85–120 ųm long, with many setae and some antennal bristles; apical segment about 140 ųm long, with many setae + 3 large and several smaller bristles. Mouthparts present: clypeolabral shield moderately well developed, with stylets; length about 400 ųm; facing posteriorly; labium absent. Wing-buds each short (about 200–220 ųm long) and rounded. Thoracic spiracles rather small: width of peritremes about 60 ųm, length of muscle plate + spiracle 160–200 ųm; small pores in peritreme not located; each spiracle without an associated group of loculate pores. Legs: metathoracic legs: lengths (ųm): coxa 336; trochanter + femur 515; tibia 530; tarsus 300; claw 90; coxae with a group of about 5–8 long setae near articulation with trochanter; trochanter with 8–10 campaniform sensilla on each side; most tibia showing little sign of deformation, but with a crease about 2/3rds along length, otherwise slightly bent; each tibia with spur-like setae along ventral margin, those distally about 35–45 ųm long; also with 2 campaniform sensilla on lateral margins about 1/2 way along length; tarsi each with 3 tarsal campaniform sensilla; all legs with many setae, those along ventral and lateral margins of tibia and tarsus spur-like; claw digitules setose, with 1 on each margin; claw without a denticle.

Comment. This specimen is labelled as having been removed from its cyst. As with the adult female which had mouthparts (see above in final discussion under adult female), it is here considered that the presence of mouthparts on this specimen is abnormal for a prepupa and was due to its manual removal from the cyst. The single prepupa of S. paranaensis described below does not have mouthparts. Neither the pupa nor the prepupa of Marchalina hellenica Gennadius had mouthparts – but then, neither did they have external wing-buds ( Hodgson & Gounari, 2006). This specimen was originally considered to be a small adult female ( Foldi, 1995), but it has wing-buds, no vulva and no oval, segmented pores on the posterior abdominal segments.

The fact that this specimen has small wing-buds strongly indicates that it is a prepupa. However, as indicated above, some of the abdominal spiracles appear to be in the process of moulting (in one case, there are 2 spiracles, with the trachea of one extending into the other; in addition there are at least two other spiracles with just the trachea emerging from the outer atrium of the spiracle, but without any further spiracles). The pupa of S. paranaensis briefly described below appears to only have a large abdominal spiracle on abdominal segment VIII, similar to that on the adult male. If one assumes that the pupa of S. garmilleri is similar (in other words, that it does not have the large, well-sclerotised spiracles found on the prepupa), then the fact that this prepupa of S. garmilleri is moulting leads to the inevitable question "What is it either moulting to – or from?" As this specimen is labelled as having been removed from a cyst, the "extra" spiracles are presumably those of the cyst.

For a comparison with the prepupa of S. paranaensis , see under the latter species.