Discochiton sarawakense Hodgson

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 : 63-65

Discochiton sarawakense Hodgson spec. n.

( Fig. 23 )

Material examined. Holotype and paratype f: MALAYSIA, Sarawak: left label: Paralecanium sp. / nr. malaianum / Tak. [crossed out], / Discochiton / sarawakense / Hodgson / Holotype and / paratype ff; right label: indet host,? Piperaceae / SARAWAK, 4th Div. / Kerangus Forest / above camp 5 / 11.x.77 / D. Hollis M9/6 / R.G.S.G.N. Mulu Exp. / 51/77 ( BMNH): 1/2adff (g; holotype left-hand specimen). Paratype nymphs: Sarawak: left label: Paralecanium sp. / nr. malaianum / Tak. [crossed out] / Discochiton / sarawakense / Hodgson / paratype 2nd/3rd-instar nymphs; right label: indet host / SARAWAK, Kerangas Forest / (above camp 5) / 11.x.77 / D. Hollis M9/5 / R.G.S.G.N. Mulu Exp. / 53/77 ( BMNH): 2/3 second/third-instar female nymphs (g, but 2 with parasitoid larvae).

Other material. MALAYSIA, Sarawak, Kuala Boram, on an undetermined host with alternate leaves and pink fruits, 11.vii.1978, V.F. Eastop # 16, 388 ( BMNH): 1/1adf (fg) + 1 adf of Paralecanium maritimum Tak. (g, split into dorsum and venter).

BRUNEI, Temburong District, forest above Kuala Belalong , 200 m alt., upper surface of leaves of unknown seedling, 8.x.1992, J.H. Martin #6135 ( BMNH): 2/9adff (g).

Note. The description is based on both type specimens; data for the non-type material is shown in […] where different.

Slide-mounted adult female. Body almost round. Length 3.75 [1.9–3.38] mm, width 3.5 [1.2–2.6] mm.

Dorsum. Derm rather uniformly sclerotised, with a fairly broad band of elongate areolations close to margin [obscure or absent on Brunei specimens], in groups or bands running radially from margin, becoming more sparse and indistinct medially; most of derm with abundant minute oval pale spots, each about 1 µm wide. Stigmatic rays present; marginal radial lines obscure, indicated by lines of pores and setae, with perhaps 13 on head between anterior stigmatic clefts, each side with 5 between stigmatic clefts and 13 or 14 on abdomen. Abdominal clear areas numbering 5 pairs but none present on prothorax [present]. Dorsal setae each short and spinose, with parallel sides and a small capitate apex, 6–7 [6–10] µm long, frequent in a sparse polygonal pattern extending submedially, absent medially; many setae each with an uneven area of paler derm surrounding the base. Preopercular pores highly convex, each about 2.0–2.5 µm wide, distributed as follows: CA1 with 0 or 1, CA2 with 0–2, CA3 with 2–8 [0–3] and CA4 with 26–30 [4–35] pores. Other pores of two sizes possibly present, both represented by small clear spots in derm, the larger about 3 µm wide, the smaller perhaps 1 µm wide; both present throughout. Anal plates almost quadrate, with outer margins subequal in length; each plate with 3 or 4 minute setae near posterior apex plus 1 small pore medially; length of plates 170–180 [120–195], combined width 135–150 [115–140] µm. Anogenital fold with 2–3 minute setae at each corner of anterior margin, each lateral margin with 1 seta anteriorly and another posteriorly.

Margin. Margin with shallow corrugations, each with short, shallow [some deep] radial lines or ridges, with mostly 4–6 corrugations between 2 setae. Marginal setae broadly fan-shaped, wider than long; width of each fan about 30–36 µm, length 21–26 [30] µm; with about 96–109 [71–109] setae anteriorly on head between anterior stigmatic clefts, each side with 43–57 [33–52] between stigmatic clefts and 81–88 [69–90] on abdomen. Stigmatic clefts quite deep, each with a narrow entrance, a sclerotised inner margin and 3 blunt stigmatic spines, median seta obviously longest; length of median stigmatic spines each 30–35 [40–57] µm; lateral spines each 25–30 [28–40] µm long. Eyespots, each in a socket 85–90 [70] µm wide; diameter of lens 25 µm.

Venter. Derm membranous, but with a complete dark border 60–75 [53–80] µm wide, with pale oval areolations throughout its length, each 5–12 µm wide. Multilocular disc-pores frequent on either side of genital opening and on preceding two segments only, each side with 7–16 on abdominal segment VII, 10–18 on segment VI and 7–14 on segment V. Spiracular disc-pores present in a narrow band mostly 1 pore wide between margin and each spiracle, with perhaps 22–27 [12–18] in each anterior band and 12 or 13 [7–11] near each cleft but otherwise absent from each posterior cleft. Ventral microducts minute, present in a group just posterior to and on either side of labium; probably present sparsely elsewhere. Ventral setae: with 2 pairs of setae between antennae; pairs of long pregenital setae on segments VII–IV (that on VII 90 –100 µm long); other setae very sparse; long setae absent from each side of anal cleft near anal plates. Antennae reduced, each with 3 or 4 segments (segmental divisions between segments III–VI unclear or absent); total length 90–125 [70–125] µm. Clypeolabral shield small, 85–95 µm long. Spiracles: width of each peritreme 33–38 [26–35] µm. Legs absent.

Comments. Adult female D. sarawakense spec. n. are somewhat similar to those of D. expansum but differ in lacking leg stubs and, in particular, in having a dark ventral marginal border with pale areolations. The non-type material from Sarawak differs quite significantly from the type material in a few character-states (size of the median stigmatic spines; number of preopercular pores; size of the anal plates and antennae; number of marginal setae, etc) but are, nonetheless, considered to be the same species. The specimens from Brunei however, are very similar to the type series. Adult D. sarawakense are also similar to D. malainum but the latter species lacks areolations in the ventral marginal band and the arrangement of the preopercular pores is quite different, with those of D. malainum forming a tight group mesad to CA4, whereas those of D. sarawakense are in loose groups surrounding both CA3 and CA4.

Host-plant.? Piperaceae .

Name derivation. This species is named after the country in which the type specimens were collected, namely Sarawak, i.e. sarawakense .

Figures

FIGURE 23. Discochiton sarawakense Hodgson, spec. n., adult female. Where A = type series, Kerangas Forest, Sarawak, and B = from Kuala Boram, Sarawak.