Platylecanium sarawakense Hodgson, 2025

Hodgson, Chris, 2025, Revision of the soft scale genus Platylecanium (Hemiptera: Coccomorpha: Coccidae), with descriptions of eight new species, Zootaxa 5646 (2), pp. 151-198 : 185-188

Platylecanium sarawakense Hodgson , sp. nov.

Material examined

Type material: SARAWAK: left label: Platylecanium / sarawakense / Hodgson / Holotype / and paratype /reddish in life; right label: host indet., upper / surface of leaves / SARAWAK / Gunung / Mulu Nat. Park , / 5g. Melinau , Camp 5 / 1.iii.1989 / J.H. Martin 5450 (1/2 adff, good, holotype specimen on right, next to locality label) ( NHML).

Non-type specimens: SARAWAK: left label: SARAWAK / Sibute, Piper nigrum / C. R . Wallace / 1.xii.1961 1942 / C.I.E. C 486; right label: Platylecanium / sarawakense / Hodgson (3/6 adff in fair condition but covered in a lot of white wax-like test and with much fungal hyphae; asymmetrical) ( NHML) . BRUNEI: left label: Platylecanium / sarawakense / Hodgson ; right label : BRUNEI, Salapon / vi. 1974 on / Piper nigrum / No. 875 / D.J. McCrae / CIE A7471 (2/3 adff, fairly good, symmetrical but with a lot of waxy test still present and attacked by fungi) ( NHML) .

Note. The two type specimens ( Fig. 13 ) are basically symmetrical but the non-type specimens from Sibute ( Fig. 14 ) are strongly asymmetrical. The description is made from the type specimens, with data for non-type Gunung specimens given in brackets where different.

Unmounted material. Apparently reddish in life; non-type specimens with a thin whitish waxy test.

Slide-mounted adult female ( Figs 13 & 14 ). Body oval and basically symmetrical (strongly asymmetrical), rounded at both ends, length 4.4‒4.5 (3.0‒4.8) mm, width 2.6‒3.2 (1.7‒2.9) mm; anal cleft about 1/7 th of body length.

Dorsum. Derm unsclerotised and therefore specimens relatively young; inner margins of stigmatic clefts only areas with obvious sclerotisation; all specimens showing a narrow margin and then a rather obscure submarginal band of areolations (latter not visible); with slightly denser derm around anal plate and possibly around each eyespot. Layout of reticulation plates not easily determined but marginal reticulation points as follows: with 13 between anterior stigmatic clefts and, on each side, 4 between stigmatic clefts and 13 on abdomen. Unsclerotised stigmatic ray arising from each stigmatic cleft indistinct; length of rays: anterior each 275‒420 (210‒465) μm, posterior each 340‒420 (?‒465) μm. Dorsal setae robust and setose, generally curved, each 6‒8 μm long, with a basal socket about 3.0 (4.0) μm wide, socket only slightly larger or subequal to that of a marginal seta (clearly larger); no dorsal setae appear to be raised on distinct fleshy bases; setae located in reticulation lines but scarcer medially. Clear areas present as in diagnosis, but rather obscure, posterior 2 or 3 (1‒3) clear areas each surrounded by group of preopercular pores, each pore mostly 3‒4 (4‒5) μm wide - subequal to width of dorsal setal basal socket, each with a distinct border and a few dark markings medially; pores usually distributed in two groups, one anterior to and other posterior to each clear area as follows: (anteriormost) CA 1, 0 (0‒2); CA 2, 1 or 2 (7‒14); CA 3, 4‒6 (11‒18); CA 4, 8‒11 (9‒18). Microducts represented by pale spots within the reticulate pattern with dorsal setae. Anal plates combined width 147‒164 (134‒143) μm, each plate clearly longer than broad, 235‒244 (176‒206) μm long, with a pointed apex; with 4 setae all close to apex, all setae 6‒8 μm long; no small pores noted; underside of each plate with a darker half-moon-shaped area along inner margin; without a deep cleft underneath on inner margin. Anogenital fold usually with 1 pair of short fine setae on anterior margin, 1‒3 (1 or 2) fine setae along each lateral margin plus a seta at posterior end of each apodeme, latter 7 (8‒10) μm long. Anal ring located at end of a long anal tube about same length as anal plates, with 6 setae; length of each anal ring seta up to 250 (230) μm. Eyespots each oval, located away from margin on dorsum; maximum width of each lens about 40 μm.

Margin. Margin crenulated. Marginal setae fairly long and setose, each about 12‒17 (15‒18) μm long (approximately twice as long as a dorsal seta) with a sharp apex; basal socket subequal to that of a dorsal seta; distribution almost entirely restricted to marginal reticulation points, each point usually with 1 or 2 setae (rarely 0 or 3); and with a slight concentration of setae near each stigmatic cleft; with 30 or 31 (22‒34) setae anteriorly between stigmatic clefts, and, on each side, 10‒14 (8‒16) setae between stigmatic clefts and 25‒29 (18‒29) on abdomen. Stigmatic clefts quite deep, each with outer margins of cleft almost touching; inner part widening and becoming quite broad, with inner margin strongly sclerotised; each cleft with 3 long, blunt stigmatic spines, middle spine normally significantly longer than lateral spines, not nearly extending out to margin; each median spine 50‒78 (26‒37) μm long, lateral spines each 33‒55 (18‒32) μm long. Inner cleft margins with or without setae. Anal cleft with margins touching along entire length.

Venter. Multilocular disc-pores each mostly with 10 loculi, present in abdominal segments VII and VI; with 21‒25 (27‒34) on each side of VII, and 33‒40 (31‒42) on each side of VI. Spiracular disc-pores, each rather small, mostly with 5 loculi, present between each spiracle and margin in a narrow band mainly 1 pore wide, with 16‒25 (6‒29) disc-pores in each anterior band and 22‒30 (8‒33) disc pores in each posterior band. Ventral microducts minute; probably present throughout. Ventral setae: a pair of long setae in segment VII, each about 75‒80 (46‒77) μm long, and a pair of shorter setae in VI, each 16‒25 μm long, setae becoming shorter more anteriorly and laterally; submarginal setae very short, only slightly longer than width of basal socket, very sparse. Antennae very reduced, each more-or-less one segmented with just a hint of scape; with setae only near apex; total antennal length 48‒58 (45‒53) μm. Clypeolabral shield 113‒120 (105‒122) μm long. Spiracles small, width of each peritreme 33‒37 (31‒35) μm. Legs only represented by small claws, sometimes impossible to locate.

Comments. Platylecanium sarawakense sp. nov. is recognisable by the following combination of character-states: (i) roundly oval body shape; (ii) margin clearly crenulated; (iii) marginal setae almost entirely restricted to marginal reticulation points; (iv) dorsal setae about half length of marginal setae; (v) anal plates slightly longer than combined width, each plate with an acute apex; (vi) underside of each anal plate with a crescent-shaped sclerotisation along inner margin; (vii) preopercular pores absent (or rare) on anteriormost clear areas; (viii) each stigmatic cleft with 3 spinose setae; (ix) multilocular disc-pores rather more abundant than on many species; (x) legs reduced to just claws without digitules, and (xi) antennae very reduced.

Although at first sight the specimens from Gunung and Sibute appear to be very different due to the asymmetry of the latter, all the above characters apply to both collections. The asymmetry of the latter is particularly obvious when looking at the number of spiracular disc-pores in each disc-pore row, with as few as 6 on one side and up to 29 on the other. As discussed above, it is here considered that asymmetry in soft scale insects is associated with the site where the nymphs settled and should not be considered as a character-state for separating species.

In having: (i) a crenulate margin; (ii) very reduced antennae; (iii) only three stigmatic spines in each cleft, and (iv) multilocular disc-pores only in abdominal segments VI and VI, P. sarawakense is very similar to P. asymmetricum and P. mesuae . It differs from P. asymmetricum in lacking the deep cleft under the inner margins of each anal plate, and from P. mesuae in having the anal plate apodemes clearly separate along their entire length (they are fused anteriorly in P. mesuae ). Platylecanium sarawakense is also very similar to P. cribrigerum but the latter (i) lacks crenulations along the margin (crenulated on P sarawakense ) (ii) the anal plates are almost as long as their combined widths, each with a blunt or rounded apex width (much longer on P. sarawakense and with a pointed apex), and P. cribrigerum has few multilocular disc-pores in abdominal segment VI (many more on P. sarawakense ). Platylecanium sarawakense is also somewhat similar to P. watsoniae , described as new below–see under that species for comparison. The new species is currently only known from Sarawak and Brunei on the island of Borneo off Piperaceae and an unknown host.

Name derivation. The species is named after the country on the island of Borneo from which most of the above specimens originated– Sarawak.

Figures

FIGURE 13. Platylecanium sarawakense Hodgson, sp. nov., symmetrical adult female.

FIGURE 14. Platylecanium sarawakense Hodgson, sp. nov., asymmetrical adult female.