Insularicoccus syzygium 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 : 14-16

Insularicoccus syzygium Hodgson spec. n.

( Fig. 2 )

Material examined. Holotype and paratype ff: PAPUA NEW GUINEA: left label: Paralecanium (crossed out) / Insularicoccus / syzygium / Hodgson / Holotype & paratype ff; right label: Syzygium sp. / ( Myrtaceae ), upper / surface of leaves / PAPUA NEW GUINEA / Morobe Prov. coast, / Buso / 9.xi.1979 / J.H. Martin coll. 2826 (BMNH): 1/3adff (holotype g, paratypes mainly with damaged venters; holotype specimen bottom right). Paratype ff, same collection data as holotype (BMNH): 2/8adff (f; many with venters separated from dorsums, but most venters incomplete; some parasitised). Paratype f: with similar collection data but collected on 5.xi.1979, J.H. Martin #2800 (BMNH): 1/1adf (f, missing some venter).

Note. The description is based on several of the clearest specimens.

Unmounted material. Derm brown (J. Martin, pers. com.).

Slide-mounted adult female. Body elongate oval; venter very asymmetrical, dorsum less so. Length 1.6–21.9 mm, width 1.4–1.5 mm. Dorsum with possible remains of polygonal plates of test.

Dorsum. Derm of younger specimens with border paler, rest of dorsum more sclerotised with faint areolations; more mature specimens more heavily and rather uniformly sclerotised. Marginal radial lines pale, short and pronounced but not reaching edge of ventral marginal band; with 11 on head between anterior stigmatic clefts, no lines from each cleft, each side with 3 between clefts and 11 on abdomen; larger broad rays from each stigmatic cleft absent. Clear areas absent from both abdomen and prothorax. Dorsal setae each small and narrow, straight, probably with a sharp apex, each about 3–5 µm long, present in a broad area submarginally, absent medially. Preopercular pores represented by 3 or 4 pairs of compound pores, located singly in approximate positions of abdominal clear areas (if these were present); each compound pore variable in size, widest about 7–9 µm, each with 4–6 satellite pores. Other dorsal pores perhaps of two types only: a larger pore, each about 3 µm wide with a sclerotised border, and a slightly smaller pore, perhaps 2 µm wide, without a sclerotised border; both rather sparse, perhaps in a polygonal pattern throughout apart from medially. Anal plates rather elongate, almost twice as long as wide, with a rounded outer angle; anterior margins slightly shorter than posterior margins; each plate with 1 or 2 small pores medially and perhaps 3 minute setae near apex; length 110–115 µm, combined width 73–75 µm; with 2 or 3 pairs of setae on anterior margin of anogenital fold, and each lateral margin with a small seta medially and a larger seta at posterior end.

Margin. Marginal ornamentation present in the form of sclerotised castellations, with about 3 or 4 between 2 marginal setae. Marginal setae mostly broad and short, each 20–33 µm wide and 16–20 µm long; with about 54–66 setae anteriorly between anterior stigmatic clefts, each side with 17–18 between stigmatic clefts, and about 44–53 along abdominal margin. Stigmatic clefts quite deep, with a lightly sclerotised inner margin, each with a group of 5 or 6 short spinose setae arranged in a narrow triangle; each group with setae about 5 µm wide and 8 long at apex, becoming slightly narrower and increasing in length to 10–16 µm near margin. Eyespots with each socket about 50 µm wide and each lens 18–20 µm in diameter.

Venter. Derm mainly membranous but, in older specimens, with an area of dense sclerotisation under apex of anal plates near anterior end of anal cleft; marginal band present, about 85 µm wide, with short, slightly darker fingers extending radially inwards from margin. Multilocular disc-pores frequent on either side of genital opening and on preceding two segments only; each side with 9–11 on segment VII, 12–14 on VI and 8 or 9 on segment V. Spiracular disc-pores present in a sparse band about 1 pore wide between margin and each spiracle; with 7–13 in each band (different on each side due to asymmetry). Ventral microducts not detected. Ventral setae: with 1 pair of interantennal setae; longer setae present medially on most abdominal segments, that on segment VII about 60 µm long; other setae considered scarce. Antennae 6 segmented, small, each with total length 115–125 µm; usually without setose setae on scape, pedicel and segments IV and V. Clypeolabral shield about 85 µm long. Spiracles small, width of each peritreme 15–17 µm. Legs represented by very small stubs, which may even be absent from some specimens.

Comments. Adult female I. syzygium spec. n. are similar to those of I. carolinensis in having: (i) a group of short stigmatic spines in each cleft, forming an elongate triangle extending onto the dorsum, and (ii) compound preopercular pores. The two species differ in having (character-states on I. carolinensis in brackets): (i) only 5 stigmatic spines in each cleft (8–20); (ii) preopercular pores represented by 3 or 4 single compound pores (4 groups of compound pores, each of 4–8 pores); (iii) marginal radial lines all very short (very long, each with a sclerotised border); (iv) legs only represented by very small leg stubs (well-developed); (v) abdominal clear areas absent (present but sometimes obscure), and (vi) most setose setae on antennae absent (all antennal setose setae present).

Host-plant. Syzygium sp. ( Myrtaceae ).

Name derivation. The species name, syzygium , refers to the host-plant genus on which this species was collected and is noun in apposition.

Figures

FIGURE 2. Insularicoccus syzygium Hodgson, spec. n., adult female. Where l = leg stub.