Ceroplastes tachardiaformis Brain

Hodgson, Chris J. & Peronti, Ana L. B. G., 2012, 3372, Zootaxa 3372, pp. 1-265 : 168-171

Ceroplastes tachardiaformis Brain

( Figs 11, 16, 17, 76; Map fig. 105)

Ceroplastes tachardiaformis Brain : 1920b: 35.

Ceroplastes tachardiaformis Brain ; Ben-Dov, 1993: 57.

Gascardia tachardiaformis (Brain) ; De Lotto, 1965: 182; De Lotto, 1978: 143.

Material examined: Lectotype ♀ (here designated): South Africa, left label: Messrs Watermeyer Br. / Aberdeen C.P. / November 1915 / on rhenosterbosch / CKB 94; right label: Ceroplastes / tachardiaformis (SANC) : 1/1 (poor).

Paralectotype ♀: as for lectotype ( SANC, CKB #94): 4/4 (poor); also top label: Ceroplastes / tachardiaformis / Syntype ( SANC): 1/1 (poor); also left label: Ceroplastes tachardiaformis Brain , Type / Aberdeen C.P. / Watermeyer Bross. Coll. / Nov. 1915 / Brain #94 ( USNM): 4/4 (fair); also scratched onto the glass in Hall’s handwriting: South Africa, Eastern Cape Province, Aberdeen, on Elytropappus rhinocerotis , Nov. 1915, Watermeyer Bros. ( BMNH): 2/2 (old, broken into bits) + 3 young (fair-poor). [This latter material is almost certainly part of the type series, as the collection data are the same as that given by Brain and it states on the slides that the specimens were sent by H.K. Munro, ex. Coll. Dept. Agric., Pretoria.]; also as previous but with the collection data on a hand-written label ( BMNH): 1/4 (3 young and 1 older specimen, fair-poor).

Also: South Africa, Eastern Cape Province, Middelburg , on Elytropappus rhinocerotis , 11.xi.1960, H.D. Brown ( SANC): 1/1 (good) ; Western Cape Province, Stellenbosch , on Stoebe cinerea , 17.ii.1969, P. Insley ( SANC #4228 ): 6/6 (good) ; Western Cape Province, Franschhoek , on E. rhinocerotis , 11.iv.1978, S. Neser ( SANC #5431 ): 2/2 (good) ; Eastern Cape Province, Grahamstown , on E. rhinocerotis , 24.iii.1933, Lubinbury ( BMNH): 2/several (mainly in bits, poor) ; Western Cape Province, 1.5 km S of Sneeuwkop , on E. rhinoceratis , 2.iii.2007, P.J. Gullan ( DCBU): 2/5 (fair-good); as previous but collected on 4.iii.2007 ( DCBU): 1/3 (poor, broken) ; Western Cape Province, Vermont , on Metalasia muricata , 20.i.2011, J. Giliomee ( BMNH): 2/3 (fair-poor) + a dipterous parasitoid .

Note. Comments and data in (..) brackets taken from De Lotto, 1978; data for Vermont specimens in [..] brackets where different).

Unmounted material. “ Adult ♀ tests aggregated in huge masses on stems of the host plant, often completely covering the stems for a distance of several inches.” “ ♀ test Tachardia -like, globular, slightly flattened above, hard, thin, brittle, almost transparent resinous brown, due to the colour of the insect inside; without protuberances but with a slight apical depression containing the opaque white larval exuvia.” “Adult ♀ denuded of wax moderately dense, globular, smooth and shiny. Caudal protuberance short, very dense, surrounded by a coarsely perforated plate” ( Brain, 1920b: 35). More recently collected specimens by Gullan had dark purple-red wax with distinct white stigmatic bands, whereas those from Vermont on Metalasia had soft white wax (see under Comment below description) .

Mounted material. Young adults broadly oval, without lateral or dorsal protuberances (cephalic and anterior lateral processes well developed; median and posterior lateral ones fused together, forming a single large, broadly rounded process). Stigmatic clefts quite deep. Caudal process conical, pointing dorso-posteriorly. Length about 0.5–?3.0+ (1.0) mm, width 0.5–?2.5+ (0.8) mm.

Dorsum. Derm membranous except for caudal process which becomes heavily sclerotised. Caudal process about 0.2–0.48 mm long; width across flattened process 0.2–0.7 mm (wider than long). Clear areas indistinct and difficult to see but perhaps sometimes with only 6 clear areas, with posterior 2 on each side fused [clearly 8]; anterior and dorsal areas sometimes with 1 or more dorsal setae. Dorsal setae each short, with almost parallel margins and a blunt apex [rather sharply-pointed setae]; length subequal to width of basal socket, latter 2.5–3.0 µm wide; present very sparsely throughout. Dorsal pores: (i) loculate microducts of intermediate type, rather small and sparse, each about 2.5–3 µm widest; pores with 1 satellite loculus generally most common but frequency variable, those on Stoebe with one satellite loculus giving: Stoebe with one satellite loculus easily most frequent, those from Vermont had pores with 2 satellite loculi common; those with 2 loculi about 3.5 µm widest; sparse and apparently randomly distributed; wax-plate lines not detected; (ii) simple microducts present in each clear area. Preopercular pores small, with about 6–15 in a narrow transverse band 2 pores wide. Anal plates with a diagonal to rather rounded anterior margin; length of plates 90–105 µm, combined widths about 90–115 µm, each with 3 long dorsal setae plus a smaller setose seta apically, longest 45–55 µm long, subapical seta 25–30 µm long. Anal tube short, apparently shorter than length of anal plates; anal ring setae each about 100 µm long.

Margin. Marginal setae very similar to submarginal setae, each stoutly setose and about 8–13 µm long; very sparse, with about 4–7 between eyespots, and, on each side, 2 between eyespots and anterior stigmatic setae, 1 or 2 between clefts and about 4 or 5 on each side of abdomen; anal lobe setae not detected [each clearly larger than marginal setae, about 25 µm long]. Stigmatic clefts quite deep, each with a small roundish to triangular group of conical stigmatic setae of rather variable shape and size; each group with 7–13 setae, becoming about 3 setae deep in each cleft, largest furthest from margin; smallest setae about 6–7 µm wide and 5.5–6 µm long and largest 10 µm wide and 8 µm long. Eyespots small and difficult to detect, each 16–20 µm wide.

Venter. Derm entirely membranous. Pregenital disc-pores abundant around genital opening (segment VII) and across preceding segment, plus 1–5 submedially on segment V and 0–2 on IV [present submedially on segments II and III]. Spiracular disc-pores present in a sparse band of 20–24 [–40] pores in anterior band and 32 [–45] in each posterior band; with usually none extending medially. Ventral microducts scarce or absent medially. Ventral tubular ducts each with inner ductule short, sometimes slightly swollen basally; present in a small group of 5–12 [–15] in cephalic region anterior to antennae, plus (rarely) up to 3 submarginally between antennae and anterior abdominal segments; also frequency variable submarginally on abdomen, occasionally present as far anteriorly as metacoxae but usually associated with anogenital fold, where common. Submarginal setae very similar to marginal setae but shorter, each about 6–8 µm long; much more frequent than marginal setae.

Antennae each with 6 segments (occasionally with a pseudoarticulation in segment III); total length 186–215 (160–175) µm. Clypeolabral shield about 145 µm long. Spiracles small, width of peritremes 30–40 [56] µm. Legs well developed, each without a tibio-tarsal articulatory sclerosis; each claw with a small denticle; claw digitules both broad; tarsal digitules quite short, subequal to length of claw digitules; dimensions of metathoracic legs (µm): coxa 83–103 [113]; trochanter + femur 105–125 (100–110) [130]; tibia 68–80 [107]; tarsus 50–65 [62] (tibia + tarsus 110–140), and claw 21–23.

Discussion. The specimens on Metalasia from Vermont were much larger and older than most of the other specimens seen and had a white test whereas those collected by Gullan were purplish in colour. It is not possible to tell what colour the specimens seen by Brain were as it seems likely that he looked at old dry material. It is therefore possible that these 2 lots of material represent cryptic or sibling species. Within the C. tachardiaformis - group, C. tachardiaformis differs from C. delottoi in having fewer than 20 stigmatic setae in each cleft, from C. elytropappi in having ventral tubular ducts in the cephalic region; and from C. paucispinus in lacking a tibio-tarsal articulatory sclerosis (present and distinct in C. paucispinus ), much shorter dorsal setae, and loculate microducts with only 1 or 2 satellite loculi (up to 4 in C. paucispinus ).

C. tachardiaformis is currently only known from Cape Province, South Africa on Elytropappus sp. , Metalasia muricata and Stoebe sp. (Asteraceae) .