Apiococcus singularis Hempel

Hodgson, Chris & Miller, Dug, 2010, A Review of the Eriococcid Genera (Hemiptera: Sternorrhyncha: Coccoidea) of South America 2459, Zootaxa 2459 (1), pp. 1-101 : 19-22

Apiococcus singularis Hempel

Apiococcus singularis Hempel, 1900: 403 .

First-Instar Nymph (considered to be female) ( Fig. 7 )

Material examined: " Types ": BRAZIL, São Paulo, Ypiranga, on Myrtaceous shrub, 1900, coll. unknown ( USNM): 1/5 first-instar nymphs: 2ff (one in good condition, other very poor) + 3mm (2 in fair condition, 1 poor) .

Unmounted material. Body elliptical and clear yellow (Hempel, 1900).

Mounted material. Body oval. Length about 310–350 µm, width 155–180 µm.

Dorsum. Derm membranous, with enlarged dermal spinules medially, these particularly obvious on meso- and metathorax and abdominal segments I – III; smaller ones present medially elsewhere. Dorsal setae of 2 types: (i) spinose and broad, with a rather rounded surface posteriorly, becoming more convex anteriorly; each about 6.5–7 µm wide, with a narrow basal socket and each raised slightly on a small membranous prominence: in 2 submedial lines, with a pair on abdominal segment I plus pairs on each thoracic segment and posteriorly on head; and (ii) setose setae, each 8–13 µm long, as follows: in a pair of mid-dorsal lines, 1 pair per segment on abdomen and thorax, and with 4 pairs on head; also with pairs of submarginal setae on abdominal segments II – IV; possibly absent elsewhere. Macrotubular ducts absent. Microtubular ducts rather large, with an oval, strongly sclerotised, apparently bilocular, pore at the end of a short outer ductule; each duct about 6–7 µm long, with a short inner ductule; distribution uncertain but perhaps rather random, with a pair on abdominal segments I – IV, 1 or 2 on most thoracic segments and a few on head. Loculate pores each 3– 4 µm wide and with 5 loculi, in 2 transverse rows across abdominal segment I, with (on each side) 11 or 12 along anterior margin and 7 or 8 along posterior margin. Anal lobes absent or rounded, membranous; without microtubular ducts; each with a long apical flagellate seta of unknown length; marginally with 2 or 3 pairs of spinose setae between long apical setae, each about 8 µm long. Anus on posterior apex, slightly oval, membranous, without an anal ring or anal ring setae; width 8 µm; with 2 rather spinose setae on either side (each about 6.5–12 µm long) plus a much longer seta, length unknown as all broken .

Margin. Marginal setae spinose, similar in shape to those on dorsum but perhaps slightly smaller, each 6– 7 µm wide and on a distinct membranous prominence; anterior setae becoming more convex and cone-like; with 4 between eyespots, 4 on each side between eyes and point opposite anterior spiracles, 2 on each side laterally between anterior spiracles and abdomen and with 1 on each side of abdominal segments I – VII. Eyespots large and oval, greatest width 11–13 µm, situated on margin near base of antennae.

Venter. Derm membranous. With 2 or 3 pairs of long flagellate setae between antennae (each about 18–20 µm long); with rather shorter setae mesad to meso- and metacoxae (11–17 µm long) and even shorter mesad to procoxae; also with a pair of setae medially on abdominal segments II – VII, each about 6–10 µm long. Submarginal setae hairlike, with a seta on each side of abdominal segments I – VII, 2 laterally between spiracles and with 3 on head; also with a submedial line of very short setae (length 2–3 µm) on abdomen (as on A. gregarius ), with 1 seta on each side of segments I – VII. Microtubular ducts apparently similar to those on dorsum: distribution uncertain but with some submedially on abdomen, in each thoracic segment and near eyespot. Loculate pores with mainly 5 loculi: with 2 or 3 immediately laterad of each peritreme, possibly in small cavity; also with 3 or 4 pores on abdominal segment I between margin and each posterior spiracle.

Antennae 6 segmented, total length 83–88 µm long; setal distribution: scape 2; pedicel 1 + a campaniform sensillum; segment III 3; IV 1; V 1 fleshy setae + 3 setose setae and VI 3 fleshy setae + about 4 setose setae; apical seta about 35 µm long. Clypeolabral shield particularly large, about 80 µm long; labium perhaps 2 segmented; with 4 pairs of setae. Spiracles very small, width of peritreme about 3 µm wide; spiracles surrounded by an oval area, perhaps a shallow cavity. Legs well developed; lengths: metathoracic leg (µm): coxa 31–33; trochanter + femur 59–63; tibia + tarsus 65–68; claw 15–18; tibia generally subequal to or slightly shorter than tarsus; setae: coxae 4 or 5, trochanter 2, femur 2, tibia 4, tarsus 3; long trochanter seta 45 µm long; tarsal campaniform sensillum present; claw with a distinct denticle; tarsal digitules on all legs capitate and equal in size; claw digitules both fine and longer than claw.

Comment. Presumed to be female as the marginal and dorsal spinose setae are approximately the same shape as those on the adult female. For a comparison of first-instar nymphs of Apiococcus with other eriococcid genera see the “Comment” section after the treatment of A. singularis (male).

First-Instar Nymph (considered to be male) ( Fig. 8 )

Unmounted material. Body elliptical and clear yellow (Hempel, 1900).

Mounted material. Body oval. Length about 250–315 µm, width 125–155 µm.

Dorsum. Basically identical to presumed female nymph described above except that type (i) spinose setae, elongate and stoutly spinose, each 10–12 µm long, each broadest medially, with a blunt apex; each with a narrow basal socket and not clearly raised on a small membranous prominence; distribution as on female crawler; and type (ii) setae as on female crawler but with only 2 pairs of submarginal setae on abdomen, on segments II and III, latter possibly shorter than former. Microtubular ducts probably distributed similarly but unclear. Loculate pores similar in structure and distribution, but with perhaps 8 on each side along anterior margin of abdominal segments I and 6–8 along posterior margin. Anal lobes similar; each long apical flagellate seta about 175 µm long. Other setae associated with anal lobes and anus distributed similarly but perhaps slightly shorter; longer seta on each side of anus about 58–62 µm long .

Margin. Marginal setae spinose, similar in shape to those on dorsum but smaller, each 7.5–9 µm long, without a distinct membranous prominence; anterior setae similar to posterior setae; distribution as on female crawler. Eyespots similar.

Venter. Similar to female crawler. Setal distribution similar to that on female crawler. Microtubular ducts as in female crawler: distribution uncertain. Loculate pores: with 2 or 3 immediately laterad of each peritreme; also with 2 or 3 pores between margin on abdominal segments I and each posterior spiracle.

Antennae similar to female crawler, total length perhaps marginally shorter, 75–83 µm long; setal distribution similar; apical seta about 55 µm long. Clypeolabral shield and labium similar. Spiracles very small. Legs well developed but possibly marginally shorter; lengths (metathoracic leg (µm)): coxa 30; trochanter + femur 60; tibia + tarsus 65; claw 13–17; other leg details similar.

Comment. The differences between the shape of the marginal and dorsal spinose setae on the presumed male and female first-instar nymphs are very clear and immediately separates these 2 lots of crawlers.

The first-instar nymphs of Apiococcus are easily separable from those of other genera known from the Neotropics in having a band of loculate pores dorsally across abdominal segment I. In addition, they have the following characters: (i) 6-segmented antennae; (ii) microtubular ducts present on both dorsum and venter; (iii) no cruciform pores; (iv) enlarged dermal spinules medially on the dorsum of meso- and metathorax and abdominal segments; (v) several loculate pores associated with each spiracle; (vi) anal plates not differentiated; and (vii) dorsal setae of clearly 2 types, a strongly spinose type and a setose type.

Figures

FIGURE 7. Apiococcus singularis Hempel. First-instar nymph, probably female, where A1 = dorsal setose seta; A2 = marginal and dorsal broad spinose setae; B = dorsal microtubular duct; C = dorsal loculate pore; E = enlarged dermal spinules; G = dorsal view of anal area; H = ventral view of anal area; P = spiracle with loculate pores; W = metathoracic leg.

FIGURE 8. Apiococcus singularis Hempel. First-instar nymph, probably male, where A1 = dorsal setose seta; A2 = marginal and dorsal broad spinose setae; B = dorsal microtubular duct; C = dorsal loculate pore; E = enlarged dermal spinule.