Choneochiton casuarinae Hodgson, Mille and Cazères, 2014

Hodgson, Chris, Mille, Christian & Cazères, Sylvie, 2014, A new genus and species of felt scale (Hemiptera: Coccoidea: Eriococcidae) from New Caledonia, Zootaxa 3774 (2), pp. 152-164 : 153-163

Choneochiton casuarinae Hodgson, Mille and Cazères spec. n.

Material examined: Holotype: adult female, NEW CALEDONIA, Pocquereux, Casuarina collina (Casuarinaceae) , 18/viii/2013, C. Mille ( MNHN): 1/2 ad female. Paratypes: same data, 27 slides with: 29 ad females, 14 2nd -instar females, 1 2nd -instar male, 18 1st -instar nymphs + 2 adult males ( MNHN: 8 ad females, 1 2nd -instar male, 5 1st -instar nymphs; AIC: 6 ad females, 3 2nd -instar females, 5 1st -instar nymphs; BMNH: 6 ad females, 3 2nd -instar females, 5 1st - instar nymphs; USDA: 5 ad females, 4 2nd -instar females, 5 1st -instar nymphs, 2 ad males; CXMNC 3 ad females). Also: La Foa, on C. collina , 02/vii/2013, C. Mille: 3/10 2nd -instar females + 2 1st -instar nymphs ( MNHN: 4 2nd -instar females; CXMNC: 2 2nd -instar females +2 1st -instar nymphs).

ADULT FEMALE (Fig. 1). [Note: data in square brackets refer to exceptionally large female, see under Comment below description.] Unmounted material. Body reddish.

Mounted material. Total length 1.1–1.6 [2.5] mm, width 0.9–1.25 [2.0] mm, more or less oval. Derm mainly membranous but with small, slightly sclerotized, nodulations and heavily sclerotized anal plates. Dorsum wider than venter.

Dorsum. Segmentation indistinct. Dorsal setae mainly short and parallel-sided, with blunt apices, each 3–5 µm long medially and up to 7 µm long near margins, all with deep basal sockets; occasionally rather pointed; apparently randomly distributed; [all extremely narrow and needle-like, but with same large basal sockets]. Macrotubular ducts extremely well developed, each consisting of a sclerotized, funnel-shaped opening, about 18–25 µm wide, 15–18 µm deep, each with a large inner ductule 16–23 µm long; total length of pore about 30–40 µm; most funnel-shaped openings with 2–4 parallel-sided blunt setae (range 0–5), each about 6–8 µm long; ducts distributed fairly sparsely in a broad marginal or submarginal band, which broadens over head and posterior abdominal segments; total about 40 per side. Microtubular ducts possibly represented by small (5–6 µm widest), oval, heavily sclerotized pores, with a short inner ductule, sparsely distributed more or less throughout but perhaps densest just anterior to anal plates. A larger roundish pore about 8–10 µm wide present, with about 4 pairs submarginally on head and 3 pairs submarginally on posterior abdominal segments. Anal lobes well developed, triangular and heavily sclerotized, each 105–125 µm [135] long and 65–75 µm [87] wide; each with unevenly-shaped pore near centre and 1–3 small pores near inner and outer margins; ventral surfaces distinctly nodulated; also with a long apical seta about 60–95 µm long, often U-shaped; each inner margin with a basal seta 18–28 µm long, plus a more apical seta 35–45 µm long; outer margin seta 25–40 µm long. Median plate (cauda) absent. Anal ring with 4 pairs of setae, each about 125–170 µm long, plus a band of pores.

FIGURE 1. Choneochiton casuarinae Hodgson, Mille & Cazères spec. nov. Adult female. On this and on Figs 2–4 , A = preantennal pores; B = quinquelocular pore; C = trilocular pore; D = sclerotized microtubular duct; E = pore of unknown homology; F = macrotubular duct; G = dorsal seta (G1 as on most adult females, G2 as on largest adult female); H = dorsal submarginal seta; J = ventral submarginal seta; K = minute seta; L = marginal seta; M = spinules; P = derm; Q = margin; R = antenna; S = labium; T = tarsus + claw; V = dorsal view of anal lobes; W = ventral view of anal lobes, and X = trochanter.

Margin. Margin fairly distinct, marked by a line of narrow dermal sclerotisations, each 3.5–4.5 µm long [much less distinct, but each sclerotisation about 10 µm long]; dermal sclerotisations on either side of marginal line tending to be less frequent. With a line of about 30–45 rather straight setae just dorsad to line of dermal nodulations, each 10– 12 µm long, sparsest on head; also with a band of setae about 3–4 setae wide, each 16–20 µm long, along ventral submargin. Eyespots dorsal, about 25 µm wide.

Venter. Derm membranous throughout, but with a few small sclerotized nodulations near margin; also with shallow dermal folds between pro- and mesocoxae, forming a rather characteristic star-shaped area. Setae all bluntly setose, similar to those on submargin, with two pairs medially anterior to scapes and a single pair medially posterior to scapes; a long pair mesad to each mesocoxa, each about 28 µm long, and a pair of shorter setae mesad to metacoxae; also in medial, submedial and submarginal lines of shorter setae (each 10–18 µm long) on abdominal segments II–VII; plus a submarginal band described under margin above; also with small tack-like setae, each about 1.5–2.0 µm long, with 1–3 posterior to each procoxa and in a group of about 4 or 5 anterior to each mesocoxa. With a pair of long suranal setae, each 70–90 [120] µm long between anal lobes; and each anal lobe with a ventral setose seta near apex, each 16–20 µm long. Microtubular ducts absent. Loculate pores, each about 4.0–5.0 µm wide, with mainly 5 loculi, with a few on head, associated with each spiracle, in a sparse band along submargin of abdominal segments and across segments VII and VIII; occasionally medially on more anterior abdominal segments. Also with two pairs of preantennal pores just anterior to each scape, one usually with 2 uneven loculi and other unilocular.

Antennae 6 segmented, total length 175–185 [225] µm; basal segment with 3 setose setae, II with 1 seta, III with 2 setae, IV with 1 fleshy seta, V with a fleshy seta + 2 rather spinose setae, and VI with 3 fleshy setae and about 6 rather spinose setae; apical seta 8 µm long. Tentorium about 100–110 [130] µm long; labium probably two segmented, basal segment with 1 very short seta and apical segment with 4 pairs of setae. Spiracles small, each peritreme about 25–33 [30] µm wide. Legs well developed; metathoracic leg segment lengths (µm): coxa 170–185 [255]; trochanter + femur 210–220 [260]; tibia 140–150 [165]; tarsus 145–157 [160]; claw 35–37; each coxa with a group of small coxal pores at distal end on anterior margin; each coxa with 5 setae; trochanter with 3, femur with 4 or 5, tibia with 2 + 2 spurs and tarsus with 2 setae + 2 spur-like setae; tarsal digitules capitate and longer than claw; claw digitules capitate, subequal to tarsal digitules, claw with a small denticle.

Comment. It is clear that all of these specimens are adult because most contain well-developed nymphs. However, the difference between the single large specimen and the remaining adult female specimens is striking, particularly in the shape of the dorsal setae (very fine on the large specimen and stout on the others) and the significantly different measurements for the limbs and other structures. It is extremely unlikely that there would be a second, very similar, species in this colony and so it is assumed that this represents an odd individual.

The presence of the very large macrotubular ducts with a large funnel-shaped opening with dorsal setae associated with their outer rim and the presence of these ducts over much of the dorsum separates this species from all other known eriococcid adult females. For instance, those on Eriococcus buxi (Fonscolombe) are very much smaller, cylindrical, without a funnel-shaped orifice, lack associated setae and are restricted to the submargin of the head ( Williams, 1985). A few other species are known to have setae associated with macrotubular pores (e.g. E. williamsi Danzig ), but in this case, the setae are merely loosely grouped around the orifice, not actually associated with the rim. Setae are also known associated with the macrotubular pores in the E. eucalypti species-group from Australia. However, in all of these other species in which the crawlers have been examined, enlarged ducts are found only in the adult females ( Cook & Gullan, 1999), whereas they are present on most other instars in Choneochiton, including the first-instar nymphs. For further comment, see under Discussion below.

SECOND-INSTAR FEMALE ( Fig. 2 ). Unmounted material. Body reddish.

Mounted material. Total length about 0.75–0.98 mm, width 0.65–0.72 mm, more or less oval. Derm mainly membranous but with heavily sclerotized anal plates. Venter slightly wider than dorsum.

Dorsum. Derm membranous, with small sclerotized nodulations in a broad marginal band and covering head and thorax; segmentation distinct on abdomen, where derm covered in small dermal spinules except near margins; medial areas of head and thorax without spinules or nodulations. Dorsal setae mainly short and parallel-sided, with blunt apices, each 5–7 µm long, shortest medially; in medial and submedial lines in abdomen, rather more randomly distributed anteriorly; setae occasionally rather pointed. Macrotubular ducts similar to those on adult female: distribution somewhat variable: with 6 or 7 pairs on head, 0 or 1 submarginally on prothorax and 0 or 1 submedially on mesothorax, plus pairs submarginally on abdominal segments I and III–VII and submedially on IV and V (or V and VI). Microtubular ducts possibly represented by small (3–4 µm widest), oval sclerotized pores, with a short inner ductule, sparsely distributed more or less throughout, but arranged segmentally on abdomen. A larger roundish pore about 7 µm wide present as 3 pairs on head and submedially on pro- and mesothorax. Anal lobes as on adult female, each 95–100 µm long and 75–80 µm wide, with an unevenly-shaped pore near centre and smaller pores near inner and outer margins; long apical seta about 145–150 µm long; basal seta on each inner margin 18–26 µm long, more apical seta 35–45 µm long; outer margin seta 20–45 µm long. Anal ring with 3 pairs of setae, each about 96–140 µm long, plus a ring of pores.

Margin. Margin indistinct perhaps marked by a line of setae similar to those on dorsum but slightly longer (7– 10 µm), number uncertain but segmentally arranged along margin of abdomen. Oval sclerotized pores, similar to those on dorsum but generally smaller, also present near most abdominal marginal setae on venter. Eyespot dorsal, about 20 µm wide.

Venter. Derm membranous throughout, but with small dermal spinules sclerotized on abdominal segments and small sclerotized nodulations near margin; also with shallow dermal folds between each pro- and mesocoxa, forming a characteristic, rather star-shaped area. Setae all bluntly setose, with a single pair between antennae; a long pair mesad to each mesocoxa, each 23–27 µm long and a pair of shorter setae mesad to metacoxae; also in medial, submedial and submarginal lines of shorter setae on abdominal segments II–VII, each about 14–20 µm long; plus a second, more marginal band of submarginal setae about 3 setae wide, sparse on head but frequent on abdomen, each about 14–20 µm long; also with small tack-like setae, each about 1.5–2.0 µm long, in a group of about 5 anterior to each mesocoxa and also 1–3 posterior to each procoxa. With a pair of long suranal setae, each 50–55 µm long, between anal lobes; and each anal lobe with a ventral setose seta near apex, each 40–45 µm long. Microtubular ducts absent. Loculate pores, each about 3.0–5.0 µm wide, with mainly 3 or 5 loculi; those with mainly 3 loculi: with 1 or 2 associated with each anterior spiracle, and 2 pores laterad to prothoracic leg; and those with mainly 5 loculi arranged segmentally in a submedial line on metathorax and abdominal segments II–VII (1 or 2 occasionally absent). Also with preantennal pores, each with 1 or 2 uneven loculi, just anterior to each scape.

Antennae 6 segmented, total length 115–130 µm; basal segment with 2 setose setae, II with 1 seta, III with 2 setae, IV with 1 fleshy seta, V with a fleshy seta + a rather spinose seta, and VI with 3 fleshy setae and about 6 rather spinose setae; apical seta 8 µm long. Tentorium about 90–105 µm long; labium probably two segmented, basal segment with 1 very short seta and apical segment with 4 pairs of setae. Spiracles small, each peritreme about 15–17 µm wide. Legs well developed; metathoracic leg segment lengths (µm): coxa 95–100; trochanter + femur 125–128; tibia 75–80; tarsus 85–95; claw 23–25; each coxa with 6 setae; trochanter with 3, femur with 4, tibia with 2 + 2 spurs and tarsus with 2 setae + 2 spur-like setae; tarsal digitules capitate and longer than claw; claw digitules capitate, subequal to tarsal digitules, claw with a small denticle.

FIRST-INSTAR NYMPH ( Fig. 3 ). Unmounted material. Body reddish.

Mounted material. Total length about 0.5–0.68 mm, width 0.35–0.50 mm, slightly more pointed posteriorly. Derm mainly membranous but with small, slightly sclerotized, nodulations and heavily sclerotized anal plates. Venter perhaps slightly wider than dorsum.

Dorsum. Segmentation moderately distinct on abdomen. Dorsal setae all short and parallel-sided, with blunt apices, each 5–7 µm long; in medial and submedial lines of about 12 setae; posterior-most setae in median line (and sometimes submedial line) significantly longer, each 30 µm. Macrotubular ducts as for adult female, each about 12– 14 µm wide and 12–14 µm deep, each inner ductule about same length, total length of pore about 25 µm; most with a single parallel-sided blunt seta, about 5 µm long; with three dorsally on head and single ducts submedially on each thoracic segment. Microtubular ducts possibly represented by small (3 µm widest), oval sclerotized pores, with 1 or 2 between most marginal setae and in a submedial line of about 6 extending from head to perhaps abdominal segment II. Other pore types absent. Anal lobes similar to those on adult, each 50–55 µm long, 43–48 µm wide; each with small pore near centre; long apical seta about 200–250 µm long; basal inner margin seta 48–53 µm long, more apical seta 50–60 µm long; outer margin seta 25–45 µm long. Anal ring with 3 pairs of setae, each about 75–100 µm long, and a ring of pores.

Margin. Margin clearly demarcated by a line of 16 or 17 long, stout setae, each about (25) 40–60 µm long; one seta per segment on abdominal segments but more frequent on thorax and head. Oval sclerotized pores, similar to those on dorsum but generally smaller, also present near most abdominal marginal setae on venter. Eyespot dorsal, about 15–17 µm wide.

Venter. Derm membranous throughout, but with very small sclerotized nodulations near margin; also with shallow dermal folds between pro- and mesocoxae, forming a characteristic star-shaped area. Setae all bluntly setose, with a single pair between antennae; a long pair mesad to each mesocoxa, each 23–25 µm long, and pairs of shorter setae mesad to other coxae; and in medial, submedial and submarginal lines of shorter setae on abdominal segments II–VII; plus a second, more marginal line of submarginal setae, longer than more inner line, each about 20 µm long, sparse on head but segmentally arranged on abdomen. With a pair of long suranal setae, each 48–55 µm long, near each anal lobe; and each anal lobe with a setose seta near apex, each 58–60 µm long. Microtubular ducts absent. Loculate pores, each about 3.0–3.5 µm wide with mainly 3 loculi, with single pores associated with each anterior spiracle, and usually with a pore mediolaterally on metathorax and abdominal segments II–VII (some occasionally absent). Also with preantennal pores, each with 2 or 3 uneven loculi, just anterior to each scape.

Antennae 6 segmented, total length 90–95 µm; basal segment with 2 setose setae, II with 1 seta, III with 2 setae, IV with 1 fleshy seta, V with a fleshy seta + a rather spinose looking seta, and VI with 3 fleshy setae and about 5 rather spinose setae; apical seta 8 µm long. Tentorium about 80–90 µm long; labium probably two segmented, basal segment with 1 very short seta and apical segment with 5 pairs of setae. Spiracles small, each peritreme about 10 µm wide. Legs well developed; metathoracic leg segment lengths (µm): coxa 43–53; trochanter + femur 88–95; tibia 50– 55; tarsus 53–62; claw 19–21; each coxa with 4 setae; trochanter with 3, femur with 4, tibia with 2 + 2 spurs and tarsus with 3 setae + 2 spur-like setae; tarsal digitules capitate and longer than claw; claw digitules capitate, subequal to tarsal digitules, claw with a small denticle.

SECOND-INSTAR MALE ( Fig. 4 ). Unmounted material. Body reddish.

Mounted material. Total length about 0.8 mm, width 0.6 mm, more or less oval. Derm mainly membranous but with heavily sclerotized anal plates. Venter slightly wider than dorsum.

Dorsum. Derm membranous, with small sclerotized nodulations in a broad marginal band and covering head and thorax; segmentation distinct on abdomen, where derm covered in small dermal spinules except near margin; medial areas of head and thorax without spinules or nodulations. Segmentation distinct on thorax and abdomen. Dorsal setae mainly short and parallel-sided, with blunt apices, each 5–7 µm long, shortest medially; approximately in medial, submedial and submarginal lines of about 12 setae; setae occasionally rather pointed. Macrotubular ducts similar to those on adult female, each with opening 15 µm wide and 7–9 µm deep and a large inner ductule 10–12 µm long; total length of pore about 18 µm; most with 1 or 2 parallel-sided blunt seta (range 0–2) about 3 µm long; with (layout slightly different on each side of single specimen): head with a pair between eyespots, plus 2 marginally, another submarginally and another more medially on one side and just one posterior to eyespot on other side; and singly on submargins of abdominal segments I, III, and V–VII + a submarginal duct on V on one side and submarginally on segments I and IV–VII. Microtubular ducts possibly represented by small (3–4 µm widest), oval sclerotized pores, with a short inner ductule, sparsely distributed across each segment. Normal tubular ducts, each with an inner ductule 8–10 µm long and a well-developed inner cup-shaped end, present sparsely across all segments.

A single larger roundish pore about 7 µm wide present more or less dorsad to each scape. Anal lobes well developed, triangular and heavily sclerotized, each 75 µm long and 55 µm wide; each with unevenly-shaped pore near inner margin and a small pore near base of inner margin; setae: with a long apical seta about 120–125 µm long; each inner margin with a basal seta 23–26 µm long, and a more apical seta 38–40 µm long; outer margin seta 25–33 µm long. Anal ring with 3 pairs of setae, dorsal and ventral pairs significantly shorter than lateral pairs, range 90–120 µm long, plus a ring of pores.

Margin. Margin indistinct, perhaps marked by a line of setae similar to those on dorsum but slightly longer (7– 10 µm), number uncertain but segmentally arranged along margin of abdomen. Oval sclerotized pores, similar to those on dorsum but generally smaller, also present near most abdominal marginal setae on venter. Eyespot dorsal, about 18 µm wide.

Venter. Derm membranous throughout, but with small sclerotized nodulations near margin; also with shallow dermal folds between pro- and mesocoxae, forming a characteristic rather star-shaped area. Setae all bluntly setose, with a single pair of inter-antennal setae between antennae and clypeus, each about 15–18 µm long, plus 3 pairs of shorter inter-antennal setae just anterior to scapes; also with 2 tack-like setae posterior to each procoxa, and a line of 4 tack-like setae anterior to each mesocoxa plus a longer seta; each metacoxa with a pair of setae similar to those on abdomen; also in medial, submedial and submarginal lines of setae on abdominal segments II–VII, each mainly 8–13 µm long; plus a band of longer submarginal setae about 3 setae wide nearer margin, each about 11–14 µm long, sparse on head but more frequent on abdomen. With a pair of long suranal setae between anal lobes, each about 40 µm long; and each anal lobe with a ventral setose seta near apex, each 40 µm long. Macrotubular ducts absent. Microtubular ducts absent. Normal tubular ducts, similar to those on dorsum but perhaps with longer inner ductules, frequent in all segments near margin, more or less forming a complete submarginal band. Loculate pores with either 3 or 5 loculi; those with 3 loculi scarce, only near spiracles, each about 3 µm wide; those with 5 loculi, each about 5 µm wide, also sometimes near spiracles but otherwise sparse throughout head, medially on thorax and in bands of 2–6 across abdominal segments II–VIII. Also with preantennal pores, each with 1 or 2 uneven loculi, just anterior to each scape.

Antennae 6 segmented (segment III with a pseudosegment), total length 125 µm; basal segment with 2 setose setae, II with 1 seta, III with 2 setae, IV with 1 fleshy seta, V with a fleshy seta + 2 rather spinose setae, and VI with 3 fleshy setae and 6 or 7 rather spinose setae; apical seta 9 µm long. Tentorium about 90 µm long; labium probably two segmented, setal distribution unclear. Spiracles small, each peritreme about 11–13 µm wide. Legs well developed; metathoracic leg segment lengths (µm): coxa 83–85; trochanter + femur 110; tibia 73; tarsus 83; claw 25; each coxa with 5 setae; trochanter with 3, femur with 5, tibia with 2 + 2 spurs and tarsus with 4 setae + 2 spur-like setae; tarsal digitules capitate and longer than claw; claw digitules capitate, subequal to tarsal digitules, claw with a small denticle.

Comment. The main differences between this instar and the second-instar female are (characters for this instar): (i) the fewer large macrotubular ducts on the dorsum; (ii) the presence of normal tubular ducts on the dorsum, and (iii) the more widespread distribution of the loculate pores on the venter.

ADULT MALE ( Fig. 5 ). (Described from two specimens in good condition)

Mounted material. Moderate sized, total body length about 1.25–1.38 mm; antennae quite long, about half body length, with moderately long fleshy setae (fs) and with capitate setae (caps) on several apical segments; body with few setae, mostly fs, each 25–35 µm long, hair-like setae (hs) few, shorter and straighter, each 15–18 µm long; all setae with blunt apices, often even appearing slightly capitate; with a large group of pores on head but other pores absent apart from in glandular pouches. Wings about 0.8 total body length and about 0.4 as wide as long.

Head. Approximately round; width across genae about 185–200 µm. Median crest not demarcated and not reticulated; with (on each side of median crest) 11–14 fs + 2–5 hs dorsal head setae and with a large group of pores on either side of dorsal mid-cranial ridge, with perhaps 20–25 pores in each group. Postoccipital ridge distinct, with lateral arms equally long. Mid-cranial ridge: dorsal ridge well developed anteriorly but only sub-equal in length to ventral part of ridge; ventral ridge extending from lateral arms posteriorly to about half-way to occipital sclerite; without any reticulation laterally but with 2 pairs of ventral mid-cranial ridge setae. Genae not reticulated; with 12 fs + 1 or 2 hs genal setae on each side just ventral to postoccipital ridge. Eyes: with two pairs of round, simple eyes; dorsal eyes placed well forward; ventral eyes perhaps on a ventral bulge; subequal in size, each 38–40 µm wide. Ocelli large, situated laterally, each 20–23 µm wide, lying between preocular and postocular ridges and not touching postocular ridge. Ocular sclerite only very lightly sclerotised, mostly around each simple eye; without reticulations. Preocular ridge short both ventrally and dorsally. Postocular ridge strongly developed, extending from close to ridge of median crest dorsally antero-laterally past each ocellus and then extending postero-laterally. Interocular ridge absent. Dorsal ocular setae absent. Ventral head setae abundant, encircling each ventral simple eyes, with a total of 20–30 on each side, mainly fs. Preoral ridge of cranial apophysis very short, about 7 µm long and 40 µm long wide.

Antennae: 10-segmented and filiform, 665–685 µm long (ratio of total body length to antennal length 1:0.8). Scape 41–45 µm long, 45–50 µm wide, with 4 hs ventrally and 1 dorsally. Pedicel arising anteriorly from scape, length 40–56 µm, width 40 µm; with a few faint concentric ridges, mainly on distal half; with about 20 fs + a campaniform sensillum. Segments III–X about 25–28 µm wide; lengths of segments (µm): III 90 –93; IV 90 –93; V 90 –92; VI 75 –77; VII 78; VIII 58 and IX 55 –60; each fs long and parallel-sided with blunt apex, 33–35 µm long; approximate number of setae per segment: III 12–15 fs + 1 hs; IV 20–25 fs + 1 or 2 hs; V 21–26 fs + 1 hs; VI 19 or 20 fs, 0 hs + 0 or 1 capitate seta (caps); VII 17 or 18 fs, 3–7 hs + 2 caps; VIII 16–18 fs, 0 hs, 3 or 4 caps + 1 antennal bristle (ab), and IX 8–13 fs, 0 hs, 3 or 4 caps + 1 ab. Segment X not constricted apically: length 50–53 µm; with 3 or 4 caps, 10–12 fs, 0 hs, 3 ab on apical third and 1 sensilla basiconica.

Thorax. Prothorax: pronotal ridge well-developed but probably not fused dorsally; extending ventrally and nearly touching proepisternum + cervical sclerite; pronotal sclerite rather large, with 1 or 2 fs pronotal setae. Medial pronotal setae absent; post-tergite fairly well developed, without post-tergital or other prothoracic setae or pores. Sternum without a median ridge but transverse ridge well developed; with a total of about 7 prosternal setae. Anteprosternal absent.

Mesothorax: prescutum oval, 125 µm long; 140–155 µm wide; sclerotised but not reticulated; prescutal ridge well developed anteriorly but quickly narrowing; prescutal suture narrow but apparently sclerotised; prescutal setae 2–4 fs. Scutum: median area sclerotised, 33–50 µm long; scutal setae: 3 pairs of fs medially and with 3 on each side level with anterior margin of scutellum; lateral margins sclerotised but not reticulated; prealare ridge quite well developed. Scutellum 135–50 µm wide, 50–55 µm long; with a distinct scutellar ridge but no foramen; scutellum with 0 or1 pair of small pores; postnotal wing process broad and extending postero-laterally. Basisternum 255–290 µm wide, 132–137 µm long; without a median ridge; bounded anteriorly by a strong marginal ridge and precoxal ridge; with 6 or 7 fs basisternal setae on each side near posterior margin; lateropleurite broad, with a narrow but distinct extension from marginal ridge along anterior and lateral margins; furca well developed, narrow-waisted, arms very divergent and extending at least 2/3rds to marginal ridge anteriorly. Mesopostnotum well developed; postnotal apophysis well developed. Area bounded anteriorly by scutellum and laterally and posteriorly by mesopostnotum membranous. Mesepisternum not reticulated; subepisternal ridge long and well developed. Postalare without reticulations; without postalare setae. Mesothoracic spiracle: width of peritreme 23–25 µm, without associated loculate pores. Postmesospiracular setae: about 18–20 fs on each side. Tegula present, with 2 or 3 fs tegular setae.

Metathorax: with 0–2 hs metatergal setae medially; metapostnotal sclerite distinct. Dorsal part of metapleural ridge absent; suspensorial sclerite absent. Posterior part of metapleural ridge well developed; episternum lightly sclerotized, with 3 or 4 fs postmetaspiracular setae; precoxal ridge apparently absent; metasternal apophysis distinct. Metepimeron sclerotised, but without setae. Metathoracic spiracle: width of peritreme 25 µm, without loculate pores. Dorsospiracular setae: 2 or 3 fs. Metasternum membranous, with about 20 anterior metasternal setae and about 25 posterior metasternal setae, mainly fs but with some hs.

Wings: hyaline, 1075–1125 µm long, 412–425 µm wide (ratio of length to width 1:0.38; ratio of total body length to wing length 1:0.8); alar lobe well developed; each wing with 2 hs alar setae but no circular sensoria. Hamulohalteres absent.

Legs: subequal in size. Coxae: I 100–105; II 95 –105; III 93 –100 µm long; setae of coxa III: 12 or 13 fs + 1 or 2 hs. Trochanter + femur: I 215; II 195–200; III 205 µm long; trochanter III with 8 or 9 fs + 2–4 hs; each trochanter with 2 elongate sensoria arranged in a line; long trochanter seta barely differentiated; femur III with about 18–25 fs + 5–10 hs. Tibia: I 230; II 215–225; III 205–210 µm; tibia III with many fs, some hs, several setae becoming spur-like along ventral margin on distal third of leg; with 2 apical spurs (tibs) on all legs, each 15–22 µm. Tarsi two segmented, proximal segment narrow and ring-like, length of both segments combined: I 83 –87; II 83 –86; III 85 –87 µm long (ratio of length of tibia III to length of tarsus III 1:0.42); tarsus III with many setae, mainly fs but with spur-like setae along ventral margin; tarsal spurs 13–16 µm long; tarsal campaniform pore present; tarsal digitules capitate, subequal to length of claw digitules and longer than claw. Claws slightly longer than width of tarsus; length III 25 µm; with a small distinct denticle; claw digitules with small capitate apices and slightly longer than claw.

Abdomen: segments I–VII: tergum and sternum unsclerotised and without obvious oval membranous areas in inter-segmental membranes. Caudal extension of segment VII absent. Without loculate pores. Dorsal setae (totals): segments I–VII: 2–5 fs + 1 or 2 hs. Pleural setae: dorsopleural setae on each side mostly with 2–4 fs and 0–2 hs; ventropleural setae: 1–4 hs on each side: III–VII: 1 hs. Ventral setae (totals): 2–4 fs + 1 or 2 hs.

Segment VIII: tergite lightly sclerotised in a transverse band; sternite with a pair of small longitudinal sclerotisations; with 8 or 9 fs ante-anal setae; sternite with 5 fs +2 hs ventral abdominal setae on each side; caudal extension large and distinct, each with 1 long hs seta (40–45 µm long) and 5 fs + 2 hs pleural setae. Glandular pouches present, shallow, each with many loculate pores restricted to glandular pouch; each glandular pouch with 2 setae of different lengths and both capitate, longer 135–150 µm and shorter 83–85 µm, both slightly capitate.

Genital segments: total length 135–150 µm, basal width 83–85 µm, divided into two sections: a broad anterior part (probably representing segment IX) and an equally long triangular posterior section (penial sheath); anterior part with anal opening dorsally near posterior margin, and with 3–7 dorsal and lateral setae; ventrally mainly sclerotized, with 1 or 2 long setae along posterior margin dorsally and laterally. Penial sheath 75–88 µm long (from anterior border to apex), width across base 58 µm, with 4 fs + 1 hs along dorsolateral margins and 1 or 2 short setae anteriorly. Apex with small penial sheath pores. Basal rod short, 8–9 µm long. Aedeagus gradually narrowing towards apex, but not extending past end of penial sheath, 66 µm long.

Comment. The adult males of C. araucariae can be quickly distinguished from all other adult male “eriococcids” in having the following combination of characters: (i) a particularly large group of pores on the dorsal surface of the head, laterad to the dorsal mid-cranial ridge; (ii) presence of an alar lobe but absence of hamulohalteres; and (iii) fleshy and hair-like setae rather similar, each frequently with a slightly capitate apex. Pores on the dorsal surface of the head are not infrequent on eriococcids but are generally few, with the possible exception of the South American Tectococcus ovatus Hempel , which has many pores of two types ( Hodgson & Miller, 2010). Almost all male eriococcids either have alar lobes and hamulohalteres, or neither. However, the presence of alar lobes without halters is not unique and is known in several other eriococcid genera ( Ovaticoccus (e.g., O. agavium Douglas ( Afifi, 1968; Hodgson, unpublished); several species of Apiomorpha (e.g., A. rosaeformis (Froggatt) (Hodgson, unpublished)). And, whilst the fleshy and hair-like setae are sometimes hard to separate, they rarely have capitate apices.

Figures

FIGURE 2. Choneochiton casuarinae Hodgson, Mille & Cazères spec. nov. Second-instar female. Lettering as on Fig. 1.

FIGURE 3. Choneochiton casuarinae Hodgson, Mille & Cazères spec. nov. First-instar nymph. Lettering as on Fig. 1.

FIGURE 4. Choneochiton casuarinae Hodgson, Mille & Cazères spec. nov. Second-instar male. Lettering as on Fig. 1.

FIGURE 5. Choneochiton casuarinae Hodgson, Mille & Cazères spec. nov. Adult male. Where A = hair-like seta?; B = fleshy seta; C = tibia, tarsus + claw; D = dorsal view of posterior end of abdomen; E = ventral view of posterior end of abdomen, and F = anterior epicranium.