Stigmacoccus asper Hempel

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 : 15-17

Stigmacoccus asper Hempel

( Fig. 5 )

Material studied. PARALECTOTYPES: BRAZIL, Pirassununga, on Inga sp. ( Fabaceae ), 28 April 1900, Hempel #17 ( USNM): 3/4 cysts, all one size, in fair to good condition; also UCDC: 2/2 cysts, one in good condition, other very poor.

Other material. COLOMBIA, Villavicencio, on Inga sp., 1972, Friedmann and Koster ( USNM): 3/5 cysts, all one size, in fair to good condition; also Blonay, on Inga sp., Sept. 14 1936, Fr. René-Paul Robd., ( UCDC): 1/ 2 in fair to good condition. GUYANA ( British Guiana), Kartabo, no host, July–Aug. 1920, W.M. Wheeler ( BMNH): 1/2 cysts in good condition, but spines very sparse; also no collection data apart from coll. W.H. Wheeler ( BMNH, ex US Bur. Entom., EEG 1b/34 No. 21): 1/1 fair but spine distribution normal. VEN- EZUELA, Maracay, on Cassia alao, Dec. 21 1938, C.H. Ballou ( USNM): 2/2 good; also as above, 4.viii.1962, M.J. Way ( BMNH): 1/1 cyst in fair condition + 1 very poor adult.

Unmounted material. Not seen.

Mounted material. All apparently of one size category, despite large size range: length 2–5.5 mm.

Dorsum. Derm covered in abundant spines throughout except medially on head and pro- and mesothorax where absent (all spines rather sparse on material from Kartabo, Guyana); each spine 23–35 ųm long, longest posteriorly, shortest anteriorly. Each abdominal spiracle surrounded by rounded bollard-like spines, each 8–12 ųm wide, as follows: segment I 80 –90 (Kartabo, Guyana 140); II 90 –120 (Kartabo, Guyana 140); III 80 –120; IV 70 –120; V 50 –75 (Kartabo, Guyana 90); VI 25–45 (Kartabo, Guyana 60); VII 1–10 (Kartabo, Guyana 55) and VIII 0. Setae: (i) hairs each 16–20 ųm long: sparse; (ii) hair-like setae not noted; (iii) minute setae: setose and spinose setae both 6–8 ųm long; both types common. Pores: (i) bilocular pores, each about 11–13 ųm wide and 11–15 ųm long; in a shallow depression; sparse throughout but mainly in intersegmental membranes on abdomen; and (ii) tubular pores, each 13–15 ųm deep, 7–9 ųm wide; 2 or 3 times as abundant as bilocular pores, sparsest in areas with spines, not restricted to intersegmental membranes on abdomen. Abdominal spiracles: outer atrium: 33–45 ųm long, 45–55 ųm wide, each with a single row of pores at distal end; opening 30–45 ųm wide; central atrium: 40–45 long, 53–60 ųm wide; inner atrium with a sclerotised "plug-like" structure about 14–18 ųm long. Anal area: (i) anal opening 80–90 ųm wide, with 17–25 pores near outer margin; (ii) band of tubercle-like pores 5 or 6 pores deep, outer diameter 165–210 ųm; with abdominal spiracles VIII lying laterad to band of tubercles, each often lying within (iii) a further band of larger rounded bollard-like spines, outer diameter of band about 250–310 ųm (Type material) (about 310–350 on Colombian and Guyana material); band of bollard-like spines broad but not always quite surrounding spiracles. Anal tube: (a) outer tube about 200–210 ųm long, about 75 ųm wide, and (b) a distal ring of 8 finger-like extensions, each 200– 230 ųm long.

Venter. Distribution of spines similar to that on dorsum, covering all of abdomen and most of thorax (rather sparse on material from Guyana); absent from head. Pore and setal distribution similar to that on dorsum, but with 3–5 spinose setae near each thoracic spiracle + a few other setae. Antennae: 20–33 ųm wide; each with 1–3 spur-like hairs (each about 25 ųm long) and 1–3 small pores on derm near margin; each pore rather unevenly rounded and 3–6 ųm wide. Clypeolabral shield 410–500 ųm long; labium 270–330 ųm long, either pointing anteriorly or laterally. Thoracic spiracles: peritreme width 57–70 ųm, with 3–4 complete rings of pores (perhaps 80?); length of muscle plate + peritreme 165–210 ųm; each spiracle with a rather elongate group of 170–200 rounded bollard-like spines, similar to those around abdominal spiracles.

Comment. The cysts of S. asper are characterised by the presence of: (i) dense spines with distinct intersegmental areas, (ii) many rounded bollard-like spines associated with each thoracic and abdominal spiracle, (iii) a broad outer band of rounded bollard-like spines around the anal opening, often broad enough to surround abdominal spiracles VIII; (iv) the presence of hairs and pores near each antenna, and (v) the peritreme of each thoracic spiracle with 3 or more complete rings of pores.

The material from Guyana is here considered to be S. asper as it agrees closely with the above description apart from (i) the dermal spines being much sparser, and (ii) the rather larger number of rounded spines near each abdominal spiracle.

Figures

FIGURE 5. Cyst stage of Stigmacoccus asper Hempel. On this and Figs 6 – 10: A = dermal spines; B = hairs and hair-like setae; C = bollard-like spines; D = anal complex; E = portion of dorsal derm; F = bilocular pore; G = tubular pore; H = cone-like spine; J = spine-like seta; K = spur-like hairs near antennae; M = anal tube; N = portion of ventral derm; P = minute seta; Q = thoracic spiracle; R = small convex pores near antennae; T = antenna; U = abdominal spiracle; V = minute sclerotised pore; W = dermal reticulation.