Rhopalotococcus dugdalei, Williams, 2007

Williams, D. J., 2007, Scale insects of the families Asterolecaniidae and Eriococcidae (Hemiptera: Coccoidea) in New Caledonia, Journal of Natural History 41 (21 - 24), pp. 1343-1366 : 1358-1361

Rhopalotococcus dugdalei sp. nov.

( Figures 3 , 4 )

Description

Inducing leaf galls, dome-shaped on upper surface, elongate-conical and truncate on lower surface. Some galls split on under-surface where crawlers possibly escape.

Body of adult female ( Figure 3 ) on microscope slide, elongate to broadly oval, 0.86– 1.25 mm long, 0.35–1.0 mm wide, widest at about mesothorax, membranous, abdomen tapering to rounded posterior end. Position of each anal lobe with a stout, flagellate apical seta 65–75 Mm long. Antennae short, 60–110 Mm long, six-segmented, becoming narrower distally, situated close together on anterior margin of head, each segment with only a few short flagellate setae except on terminal segment where longest seta about 35 Mm long; fleshy setae on last two segments about 20 Mm long. Legs well developed, slender, hind coxa 30–50 Mm long, hind trochanter + femur 95–130 Mm long, hind tibia + tarsus 95–125 Mm long. Claw slender, about 20 Mm long, with a minute denticle and a pair of knobbed digitules conspicuously longer than claw. Ratio of lengths of hind tibia + tarsus to hind trochanter + femur 0.95–1.00. Ratio of lengths of hind tibia to tarsus 0.72– 1.00. Distal trochanteral seta about 50 Mm long; hind coxa without translucent pores. Labium 45–60 Mm long, shorter than clypeolabral shield. Anal ring ventral, situated well anterior to apex of abdomen, semicircular, sclerotized, joined anteriorly by a very thin rim, ring about 25 Mm wide, 15 Mm long, non-cellular, with two pairs of short setae, each about 5.0 Mm long, and a pair of lateral setae, each about 15.0 Mm long. Eyes 25–30 Mm in diameter.

Dorsal surface with short, slender flagellate setae, mostly about 10 Mm long, situated mainly across middle of segments. Extremely slender elongate microducts, each about 7.0 Mm long, scattered on posterior abdominal segments, elsewhere sparse across segments.

Ventral surface with similar setae to those on dorsum, not numerous. Macroducts present, each about 12 Mm long, 1.5 Mm wide, sparse, occurring in groups of one to three on submargins of abdominal segments IV–VI, and one or two present medially on each segment of thorax. Microducts, same as on dorsum, a few scattered on anal lobe segment and a few present anteriorly around margins. Quinquelocular pores, each about 5.0 Mm in diameter, present on abdomen in almost single rows medially across abdominal segments V and VI and submedially on abdominal segments II, III, and VII, one or two also present medially on abdominal segment VIII; others present in groups of two to four next to each spiracular opening.

Second-instar female ( Figure 4 )

Body on microscope slide, elongate oval, membranous, 0.75–0.85 mm long, 0.28–0.32 mm wide, widest at about mesothorax; abdomen narrowing posteriorly to rounded posterior end. Position of each anal lobe with a flagellate apical seta about 65 Mm long. Antennae situated on anterior head margin, 50–90 Mm long, seven-segmented. Legs well developed, slender, hind coxa 30–45 Mm long, hind trochanter + femur 70–90 Mm long, hind tibia + tarsus 95–100 Mm long. Claw slender, about 15 Mm long, with a minute denticle near apex and a pair of knobbed digitules longer than claw. Ratio of lengths of hind tibia + tarsus to hind trochanter + femur 1.11–1.35. Ratio of lengths of hind tibia to hind tarsus 0.72–1.11. Distal trochanteral seta about 50 Mm long. Labium about 50 Mm long, shorter than clypeolabral shield. Anal ring ventral, situated a short distance from apex of abdomen, semicircular and sclerotized, 25 Mm wide, 15 Mm long, joined at anterior end by an extremely narrow rim; sclerotized area with four minute setae, each about 5.0 Mm long, and two lateral setae each about 15.0 Mm long.

Dorsal surface with flagellate setae, mostly 30–35 Mm long, noticeably longer than in adult female, distributed across middle of segments in more or less single rows. Macrotubular ducts present of two sizes. A larger type with shallow cup, about 18.0 Mm long, cup about 3.0 Mm wide, present in rows of four to six across middle of abdominal segments II–VI, usually two present on abdominal segment VII, more numerous in rows on head and thorax. A smaller type of duct with deeper cup, about 10 Mm long, cup about 2.0 Mm wide, interspersed with larger type but less frequent. Microtubular ducts about 7.0 Mm long, same as in adult female, represented by one or two at posterior end of abdomen.

Ventral surface with similar flagellate setae to those on dorsum. Macrotubular ducts present of two sizes. A small type, same as small type on dorsum, present in submedial clusters of four to six on abdominal segments V–VII. An intermediate size duct, larger than small ducts but smaller than large dorsal ducts, about 12 Mm long, with orifice surrounded by thick hyaline rim about 3.0 Mm in diameter, occurring singly on submargins of thorax and abdominal segments II–VI, a few also present in medial area of thorax. Microtubular ducts, same as on dorsum, sparsely distributed around margins of most abdominal segments. Quinquelocular pores, minute, about 3.50 Mm in diameter, present next to spiracular openings, usually two or three present next to each mesothoracic spiracle and singly or in pairs next to metathoracic spiracles.

Material examined

Holotype: adult ♀, New Caledonia, Mt Koghis , inducing galls on leaves of Metrosideros sp. , 5 October 1978 (coll. J. S. Dugdale), No. 13 ( NZAC) . Paratypes: New Caledonia, same data as holotype, 15 adult ♀♀, three second-instar ♀♀, one first-instar nymph ( NZAC) , 12 adult ♀♀, one second-instar ♀ ( BMNH) , one adult ♀ ( USNM) , one adult ♀ ( IANC) .

Etymology

The species is named after John S. Dugdale, who collected the species and sent other species from New Caledonia for study.

Comments

This species can be separated easily by the characters discussed in the key. All legs of the adult female of R. dugdalei are about the same size, whereas in R. metrosideri the hind legs are noticeably longer. The galls are unlike any of the galls induced by scale insects on Metrosideros discussed and illustrated from New Zealand by Henderson and Martin (2006). They appear to resemble the galls induced by Tectococcus ovatus Hempel , a South American species found on the leaves of Psidium spp. , another genus of Myrtaceae . Galls induced by T. ovatus are reported to be convex on one side of the leaf and acuminate on the other side ( Gullan et al. 2005).

Figures

Figure 3. Rhopalotococcus dugdalei sp. nov., adult female.

Figure 4. Rhopalotococcus dugdalei sp. nov., second-instar female.