Paralecanium zonatum (Green)

Chris J. Hodgson & Douglas J. Williams, 2018, Revision of the soft scale genus Paralecanium (Hemiptera: Coccomorpha: Coccidae) with the introduction of three new genera and twenty new species, Zootaxa 4443 (1), pp. 1-162 : 138-140

Paralecanium zonatum (Green)

( Fig. 58 )

Lecanium zonatum Green, 1904 , 245. Type data: SRI LANKA: Peradeniya, on Garcinia spicata . Syntypes, female. Type depository: BMNH, London, England, U.K.

Paralecanium zonatum ; Sanders, 1906, 9. Change of combination.

Material examined. Lectotype f (here designated): SRI LANKA (as Ceylon): top label: CO-TYPE in black on an oval label + Lectotype in red on a narrow label; bottom label: Lecanium / zonatum / Green / from / Garcinia spicata / R.B.G. [Royal Botanic Gardens] / Peradeniya / Ceylon. Feb. 1900 (BMNH): 1/1 mature ad ff (f-g, with half of venter missing). Sri Lanka (as Ceylon): top label: TYPE in red on round label; bottom label: Lecanium / zonatum / Green / from / Garcinia spicata / Peradeniya, Ceylon / EEG coll. Feb. 1900 (BMNH): 1/1adf (p, almost all venter missing).

Note. The description is based on both specimens.

Unmounted material. “Adult female flat, with an abruptly sloping margin and an inconspicuous narrow median longitudinal ridge, on each side of which is a series of polygonal scars, followed by lines radiating towards the margin. Median area dark purple-brown, followed consecutively by a reddish, a whitish and a narrow transparent greenish zone and a dark purple-brown marginal area.” “Length 3.0 mm. Breadth 2.5 mm.” “Habitat on undersurface of leaves of Garcinia spicata (an indigenous tree). Peradeniya. February.” (Green 1904, p. 245).

Slide-mounted adult female. Body oval, rounded at both ends. Length 2.8–3.0 mm, width 2.4–2.6 mm.

Dorsum. Derm with a broad medial area of fairly uniform sclerotisation but with a broad sclerotised submarginal band with a few areolations, each mainly 10–17 µm widest; derm between submarginal and medial areas of sclerotisation more or less unsclerotised. Marginal radial lines absent but position indicated by distribution of setae and small dorsal pores, as follows: 11 or 12 lines between anterior stigmatic clefts, a line present from each stigmatic cleft; each side with 3 lines between clefts and 11 on abdomen. With 4 pairs of clear areas submedially on abdomen (obscure on non-lectotype specimen), most distinct towards anterior; none found on prothorax. Dorsal setae difficult to detect due to heavy sclerotisation but thought to be narrow, more or less parallel-sided with a blunt apex but perhaps sometimes slightly clavate, each 7–9 µm long; with 1 or 2 setae in each marginal radial line; apparently absent more medially. Large dorsal pores, each 4 µm wide with visible micropores, present in a sparse submedial band extending from anal plates to head, with about 30 pores on each side; small simple pores represented by smaller clear spots in derm, each about 2.0–2.5 µm wide, sparse but possibly in a polygonal pattern, some pores appearing to be bilocular. Anal plates each much longer than wide, anterior margin clearly shorter than posterior margin, with a sharp outer angle; each plate with 2 small pores medially and 2 small setae on inner margin near apex; length of plates 220–225 µm, combined width about 120 µm (ratio of length to width 1: 0.54). Anogenital fold with 1 pair of small setae along anterior margin, each lateral margin with perhaps 2–4 setae.

Margin. Marginal ornamentation present as shallow corrugations, with normally 2 or 3 corrugations between each pair of marginal setae. Marginal setae broadly fan-like, slightly longer than wide; width of each fan 25–28 µm, length 30–35 µm; with 88–106 setae anteriorly between anterior stigmatic clefts, each side with 36–42 between stigmatic clefts, and 86–106 along abdominal margin. Stigmatic clefts quite deep, each with a sclerotised inner margin and 3 stigmatic spines, each rather parallel-sided; median spine longest; length of each median spine 33–35 µm, each lateral spine 26–33 µm long. Eyespots each more or less round; width of socket about 60 µm widest, diameter of lens about 25 µm.

Venter. Membranous apart from ventral sclerotised band about 105 µm wide, with dark radial finger-like sclerotisations. Multilocular disc-pores present around genital opening and probably on preceding segment only (venter significantly damaged here), each side with possibly 16 pores on abdominal segment VII and 16 on segment VI. Spiracular disc-pores present in a narrow band 1 pore wide between margin and each spiracle, with 15 pores in each anterior band and 20 pores in each posterior band. Ventral microducts not detected. Ventral setae: with 2 pairs of interantennal setae; a pair of long pregenital setae on abdominal segments VII, each about 105 µm long, and pairs of longish setae (each about 55–60 µm long) also present medially in other abdominal segments; also with several long setae (each about 60–65 µm long) associated with meso- and metathoracic coxae, plus 2 mesad to procoxae; other setae very sparse. Antennae 6 segmented (only 1 antenna present); total length 205 µm; apical segment about 60 µm long; apical seta about 20 µm long. Clypeolabral shield small, about 105 µm long. Spiracles small, width of each peritreme about 23 µm. Legs small but with trochantero-femur and tibio-tarsal segmentation; dimensions of hind leg (µm): coxa 70, trochanter + femur 85, tibia 34, tarsus 58; claw about 7–8; tarsal digitules slightly longer than claw digitules, with capitate apices; at least one claw digitule broad (other not visible); claw without a denticle; setal distribution: coxa 5; trochanter 1; femur 2; tibia 1 and tarsus 2 or 3.

Comments. Adult female P. zonatum are fairly easily identified (based on the 2 fairly mature specimens examined) in having: (i) elongate anal plates; (ii) long ventral setae on the thorax near each coxa, and (iii) by the distribution of the sclerotisation on the dorsum. Other important features are: (i) clavate dorsal setae; (ii) the large dorsal pores actually small in size, each about 4 µm wide; (iii) elongate anal plates, and (iv) the marginal setae tending to be rather narrow, i.e., longer than broad.

Host-plant. Garcinia spicata (Clusiaceae) .

Figures

FIGURE 58. Paralecanium zonatum (Green), adult female.