Aculeococcus morrisoni Lepage

Hodgson, Chris & Miller, Dug, 2010, A Review of the Eriococcid Genera (Hemiptera: Sternorrhyncha: Coccoidea) of South America 2459, Zootaxa 2459 (1), pp. 1-101 : 11-14

Aculeococcus morrisoni Lepage

Aculeococcus morrisoni Lepage 1941: 141–145 .

Material examined. No data: USNM: 1/4adff (in good condition) and 4 embryos (inside egg membranes, in fair condition) + 1/3 adff (in fair to good condition). The first slide lacks data except for a small label that has the date “24- VIII- 3?” [the second number of the year is unclear but it does not look like a 9] and the number “61.” The second slide was sent to Morrison with a letter by Lepage dated February 2, 1939 with no data other than it was “No.1” from “ Brazil ” and was found “in galls on leaves.” In the letter, Lepage asked for assistance in identifying the species and suggested that it might be similar to the South African genus Calycicoccus . After considerable study, Morrison responded in a letter dated February 11, 1941, indicating that, although he could see several similarities with Calycicoccus , he found sufficient differences “to justify the erection of a distinct new genus.” It seems highly probable that at least the second slide is part of the type series. The identity of the host plant remains unknown.

Adult Female ( Fig. 3 )

Unmounted material. Females inducing elongate, pointed, conical galls on upper surface of leaves of host plant. Each gall with a small opening on lower surface of leaf, through which white waxy filaments extrude. Galls of perhaps 2 sizes, largest 2 mm wide at base and up to 17 mm long. Female lives within a cavity within gall, which it does not appear to fill completely. Body bulbous, becoming wider than long.

Mounted material. Body approximately pear shaped but anterior 2/3rds, becoming very swollen and membranous; division into head, thorax and abdomen complex. Head located dorsally in centre of dorsal surface, with labium pointing anteriorly and with antennae and eyespots at posterior end (see below); rest of membranous dorsal surface and all of swollen ventral surface representing thorax, with prothoracic legs and anterior spiracles located laterad to mouthparts on dorsal surface, and meso- and metathoracic legs and posterior spiracle located posteriorly on ventral surface. No indication of any segmentation on membranous areas. True dorsum represented by a diamond-shaped, heavily sclerotised, area located medially at posterior end of globular body. True dorsum showing distinct segmentation, including, at anterior end, a small area of sclerotisation with antennae and eyes, clearly representing dorsal surface of normal head. Dorsal surfaces of thoracic segments present immediately posterior to sclerotised part of head, while dorsal surface of abdomen forms posterior half of diamond, narrowing to pointed anal lobes; anterior end of abdomen quite narrow where it joins globular anterior section; thorax and abdomen therefore heavily sclerotised dorsally but both almost entirely membranous ventrally. Sclerotisation on dorsal surface probably becoming slightly more extensive on older specimens. Total body length 1.79–2.18 mm, width 1.6–1.86 mm.

Dorsum. True dorsum mainly heavily sclerotised, represented by a diamond-shaped area covering abdomen posteriorly and an equal area anteriorly, with a small part of head forming anterior point of diamond. Dorsal setae of 2 types: (i) setose setae, each 3–5 µm long, on thoracic segments and anterior 2 abdominal segments, possibly randomly distributed on thorax but with 1–4 on each segment; and (ii) strongly spinose setae on posterior 6 segments of abdomen, shortest on segment III (length 27–37 µm) and longest on segments VI and VII (length 39–67 µm); totals per segment as follows: III 5 ; IV 6 ; V 4 or 5; VI 3 or 4 and VII 4 . Macrotubular ducts absent. Dorsal microtubular ducts possibly present on abdominal segments II – IV, indicated by minute pores in sclerotisation; structure unknown. Loculate pores with mainly 5 loculi, restricted to broad bands across abdominal segments III – VII, frequency per segment: III 0–6; IV 57–103 ; V 74–140 ; VI 63–96 and VII 37–69 . Other pores absent. Eyespots each 16–19 µm wide, surrounded by an area of dimpled sclerotisation. Anal lobes strongly developed, outer margins of lateral lobes converging and with a long median lobe (length 23–32 µm long) medially. Anal lobe setae as follows: dorsally with larger spinose setae on lateral margin 46–67 µm long, and shorter setae on inner margin 20–23 µm long; ventrally with anterior suranal setae (laterad to anus) 18–26 µm long; setae along ventral outer margin: posterior seta 20 µm, middle seta 55–70 µm and anteriormost seta 27–42 µm long. Anal ring with 6 anal ring setae, each 62–70 µm long, situated beneath median lobe; with a denser area of sclerotisation around median lobe .

Margin. Undefined on globose anterior portion of body but marked on abdomen by margins of sclerotisation. Marginal setae probably absent.

Venter. True venter making up probably at least 90% of body and almost entirely membranous, with segmentation apparent on abdomen. Setae on most of venter sparse and rather short, each 6–10 µm long; with a long seta associated with each meso- and metacoxa, each about 30–35 µm long and another long seta "anterior" to each antenna, each about 30 µm long; frequency in each abdominal segment as follows: II 2?, III 1–4, IV 1–6, V – VII 4–9; each abdominal segment with 2 setae on each side near "margin"; with about 3 pairs of short setae between antennae; other setae rather randomly placed. Macrotubular ducts absent. Ventral microtubular ducts very small, each 4–5 µm long, with 8-shaped inner sclerotisation; sparse, distribution uncertain. Loculate pores of similar structure to those on dorsum, restricted to thorax, with 2–5 associated with anterior spiracle and 0–2 with posterior spiracle; also with a few laterad to clypeolabral shield and "anteriorly and laterally" on thorax.

Antenna 1 segmented, each about 23 µm long, located close together at anterior end of sclerotised area, with some dimpled sclerotisation between; each with about 5 fleshy setae and 5 setose setae, 2 of latter quite long (39–45 µm long). Clypeolabral shield about 96–110 µm long, but with 2 large, rather wing-like, sclerotised apodemes, each 195–215 µm long and 125–143 µm wide arising from the tentorial box; labium 1 segmented, with 4 pairs of setae. Spiracles: width of peritremes 15–17 µm. Legs all very weak, with segmentation indistinct; lengths (metathoracic leg): coxa large, oval, heavily sclerotised, 70–90x53–70 µm (coxae very small on other legs); trochanter + femur indistinct; tibia + tarsus perhaps 35–49 µm long, claw 20–32 µm long, with a small denticle; setae very few; tarsal digitules well developed and longer than claw, claw digitules shorter than claw, capitate; without translucent pores on hind legs. Vulva not detected.

Comment. For a comparison of the adult female of Aculeococcus with other eriococcid genera see the “Comment” section after the generic diagnosis of Aculeococcus .

First-Instar Nymph (gender not determined) ( Fig. 4 )

Unmounted material. Yellow.

Mounted material. Body elliptical. Length about 305–350 µm, width 150–155 µm.

Dorsum. Derm membranous, without clear dermal spinules medially. Dorsal setae of 2 types: (i) spinose, broad, nipple-shaped, each about 5 µm wide and 5–6 µm long, with basal socket broader than base of seta: in 2 medial lines, with a pair on 1st abdominal segment plus pairs on pro-, meso- and metathorax and 2 pairs on head; also present submarginally on abdominal segments III, II and I, and on meta- and mesothorax, plus submedially on prothorax and posteriorly on head; and (ii) a conical seta, much narrower than type (i), each about 10 µm long, as follows: in 2 medial lines, on abdominal segments V – VII. Macrotubular ducts and loculate pores absent. Microtubular ducts long and narrow, each 5–6 µm long, with a lightly sclerotised dermal pore and a very short inner ductule; apparently distributed as follows: a pair submedially on abdominal segments VIII, V and II, plus on mesothorax; also submarginally on abdominal segment IV, pro-, meso- and metathorax and perhaps with 2 pairs on head. Anal lobes membranous, apparently present (only visible on 1 specimen not in egg membrane); possibly with a microtubular duct near base; each with a long apical flagellate seta about 150–170 µm long; with 2 pairs of spinose setae along inner margins, each slightly bent and 8–10 µm long; each anterior and posterior suranal seta 12–13 µm long. Median plate present between anal lobes, about 10 µm long and 5 µm wide. Anus appearing ventral, possibly with a narrow sclerotised anal ring with 3 pairs of setae .

Margin. Marginal setae spinose, similar in shape and size to type (i) on dorsum: with 8 between eyespots, 1 just dorsad to each eye, 5 on each side between eyes and point opposite anterior spiracles, 5 on each side laterally between anterior spiracles and abdomen and 1 on each side of abdominal segments I– VII. Eyespots large and oval, greatest width 16 µm, situated on margin posterior to base of antennae .

Venter. Derm membranous. With 3 pairs of long flagellate setae between antennae (each about 25 µm long); with a rather longer seta mesad to each meso- and metacoxa (about 33 µm long); none apparently near precoxae; also with a pair of setae medially on abdominal segments V, VI and VII, each 8–12 µm long. Submarginal setae minute, spinose (each about 3 µm long), with a seta on each side of abdominal segments I– VIII and 2 laterally between spiracles; none apparent on head. Macrotubular ducts absent. Microtubular ducts similar to those on dorsum, with 1 submarginally on each side along anterior margins of abdominal segments I–V, meta- and mesothorax and on head, just posterior to eyespot. Loculate pores with 5 loculi: with 1 pore immediately laterad of each peritreme.

Antennae possibly 3 segmented, total length 43–45 µm long; setal distribution possibly as follows: scape 3; pedicel 1 + a campaniform sensillum; segment III 3 fleshy setae + about 3–5 setose setae; apical seta about 50 µm long; other lateral long seta 40 µm long. Clypeolabral shield not yet clearly developed but labium distinct, 1 segmented; about 25–27 µm long, with 3 pairs of setae near apex (longest 20–25 µm long) and another pair more basally. Spiracles very small, width of peritreme about 2.5 µm wide; spiracular apodeme apparently absent. Legs hard to discern but perhaps lengths (metathoracic leg (µm)): coxa 21; trochanter + femur 50; tibia + tarsus 45–52; claw 13–14; tibia generally subequal to or slightly longer than tarsus; setae: coxae 3, trochanter perhaps only 1, femur 3, tibia 1, tarsus 4; long trochanter seta 8–12 µm long; tarsal campaniform sensillum present; claw quite elongate, with a distinct denticle; both tarsal digitules on all 3 pairs of legs finely capitate and equal in size; claw digitules similar and probably longer than claw.

Comment. The first-instar nymph of A. morrisoni is separable from the other known first-instar nymphs from the Neotropics in having the following combination of characters: (i) antennae 3 segmented; (ii) dorsal spinose setae mainly spinnerette shaped; (iii) each anal lobe apparently without a spinose seta on outer margin; (iv) microtubular ducts present on both dorsal and ventral surface; (v) loculate pores restricted to just laterad to each spiracle; (vi) no cruciform pores; and (vii) claw digitules similar. It is somewhat similar to the first-instar nymph of Pseudotectococcus anonae in having 3-segmented antennae and anal lobes but the latter has: (i) rather parallel-sided spinose dorsal setae; (ii) cruciform pores; (iii) no microtubular ducts on the venter; (iv) a spinose seta on the outer margin of each anal lobe; and (v) dissimilar claw digitules.

Figures

FIGURE 3. Aculeococcus morrisoni Lepage. Adult female, where B = ventral microtubular duct; G = dorsal view of abdomen; H = ventral view of abdomen; L = ventral loculate pore; P = posterior spiracle; Q = mouthparts with associated apodeme; W = metathoracic leg, and Y = head area showing antennae and eyespot.

FIGURE 4. Aculeococcus morrisoni Lepage. First-instar nymph inside egg-case; where A = dorsal spinose seta; B = dorsal microtubular duct; G = dorsal view of anal lobes; H = ventral view of anal lobes; K = ventral microtubular duct; L = ventral loculate pore; R = marginal seta; V = antenna, and W = metathoracic leg.