Platylecanium coelogyne 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 : 160-162

Platylecanium coelogyne Hodgson , sp. nov.

Material examined

THAILAND: left label: Thailand / ex Coelogynae sp. stem / xi.10. [19]72 / Hawaii 20014 / L.H. Tengen / Balsam; right label: Platylecanium / coelogyne / Hodgson / Holotype and paratype ♀♀ (1/2 adff, Holotype specimen (here designated) smallest and marked with an arrow, other specimen a paratype (latter lacking venter) ( USNM). Other paratypes: collection data as previous (1/2 adff, 1 specimen lacking a venter) ( USNM). All specimens slightly damaged and all paratype specimens heavily sclerotised. These specimens were clearly intercepted by the U.S. phytosanitary services in Hawaii .

Unmounted material. Unknown.

Slide-mounted adult female ( Fig. 3 ). Body oval and symmetrical, length 2.9‒3.5 mm, width 2.0‒3.0 mm; anal cleft quite long, about 1/5 th ‒1/6 th of body length.

Dorsum. Derm sclerotised throughout, with little sign of heavier sclerotisation apart from a little in each stigmatic cleft and along sides of anal cleft. Derm with some short, rather parallel, markings marginally and then with a complete submarginal band of areolations, each areolation quite large and roundish; rest of derm with a pattern of mainly 3‒5-sided markings with minute spots. Reticulation plates possibly in 4 longitudinal bands on each side, but reticulation lines indistinct; marginal reticulation points reasonably distinct, with 13 points on head between anterior stigmatic clefts and, on each side, with 4 between stigmatic clefts and 13 on abdomen (latter including line close to anal cleft, often difficult to distinguish). Each stigmatic cleft without an unsclerotised ray extending medially. Dorsal setae each 8‒12 µm long (much shorter than marginal setae), robustly setose, mostly slightly curved with a fine apex; each socket about 4‒5 µm wide; a few setae each raised on a distinct fleshy mound (not very obvious) with seta located on apex; setae restricted to within reticulation lines and most abundant towards margin, becoming distinctly scarce medially. Clear areas present, as in diagnosis but unusually large, each clear area surrounded by a group of preopercular pores, each pore about 4.0 µm wide (subequal to width of a setal socket) with a granulate surface and a distinct border; pores very few, distributed as follows: (anteriormost) CA 1, 0; CA 2, 0 or 1; CA 3, 3‒6, and CA 4, 3‒6. Dorsal microducts minute, each about 1 μm wide, located in an unsclerotised spot within reticulation lines. Anal plates together almost quadrate, each plate 170‒190 µm long, combined width 185‒190 µm, with anterior and posterior margins subequal in length, rounded laterally and with a rather blunt apex; anterior and posterior margins strongly sclerotised, with sclerotisation ending rather abruptly about 2/3rds along length of posterior margin, with a distinct indentation at this point; inner margin slightly wavy. Each plate with 4 setae, distributed as in diagnosis, that near apex 25‒30 µm long; each plate also with a few small pores. Anogenital fold with 2 pairs of short fine setae on anterior margin, each lateral margin possibly without setae along middle part but with a short seta at posterior end of apodeme. Eyespots slightly oval, located away from margin on dorsum; greatest width 22‒35 μm.

Margin not crenulated. Marginal setae clearly longer than dorsal setae, setose, each 13‒22 μm long, with mainly 2 setae (occasionally only 1) approximately associated with each marginal reticulation point, plus a few others between reticulation points; with 25‒35 setae between anterior spiracular clefts and, each side, 8‒14 between stigmatic clefts and 22‒30 on abdomen. Stigmatic clefts quite deep, each with outer margins of cleft nearly touching; inner part of cleft quite broad, with inner margin strongly sclerotised; each cleft with 3 stigmatic spines, all very short, blunt and subequal in length, each 16‒26 μm long; margins of each cleft without setae but usually with 1 or 2 on each side of cleft opening. Anal cleft with margins touching.

Venter. Multilocular disc-pores each 5‒6 μm wide, each with mainly 10 loculi, frequent on either side of genital opening and on preceding segment only; frequency not very clear but each side of segment perhaps with: VII, 16; and VI, 25‒41. Spiracular disc-pores each about 3.0‒3.5 μm wide with 5 or 6 loculi, present in a band 2 or 3 pores wide between each spiracle and margin; with at least 45 in each band. Ventral microducts minute, each about 1 μm wide; distribution unknown. Ventral setae: long pregenital setae present on abdominal segments VI and VII, rather robust, those on VII each 85‒90 µm long, those on VI each 58‒65 μm long, plus a few others each 28‒30 μm long; setae sparse elsewhere but smaller submarginally that medially. Antennae only slightly reduced, segmentation not very clear; each antenna with at least 4 or 5 segments but with normal 3 apical segments fused; with perhaps 2 small setae on scape, a campaniform pore on pedicel and possibly 5 fleshy setae and perhaps 4 setose setae on apical segment; total antennal length 150‒163 μm. Clypeolabral shield 160‒170 μm long. Spiracles small, width of each peritreme 35‒43 μm. Legs minute, each more-or-less reduced to a claw with no digitules; only prothoracic leg detected with certainty.

Comments. Platylecanium coelogyne sp. nov. is characterised by having the following combination of character-states: (i) moderately developed antennae showing distinct segmentation; (ii) each stigmatic cleft with three short, blunt stigmatic spines, all subequal in length; (iii) absence of unsclerotised rays extending medially from each stigmatic cleft; (iv) margin not crenulated; (v) marginal setae longer than dorsal setae and rather abundant; (vi) anal plates about as long as their combined widths; (vii) sclerotisation along posterior margin of each anal plate stopping abruptly at a notch in the posterior margin; (viii) preopercular pores very few, almost entirely restricted to posterior two clear areas; (ix) legs present but reduced to just claws, and (x) spiracular disc-pores in bands 2 or 3 pores wide.

The presence of: (i) moderately developed antennae showing distinct segmentation, (ii) very short, blunt stigmatic setae, and (iii) absence of unsclerotised rays extending medially from each stigmatic cleft immediately separates P. coelogyne from all other known Platylecanium species. Platylecanium coelogyne is currently only known from this interception in Hawaii on the orchid Coelogyne sp., imported from Thailand.

Name derivation. The species name coelogyne (a noun in apposition) is after the orchid host-plant genus on which it was collected, Coelogyne Lindl.

Figures

FIGURE 3. Platylecanium coelogyne Hodgson, sp. nov., adult female.