Crisicoccus azaleae

Crisicoccus azaleae (Tinsley 1898)

[Japanese common name: Azarea-kona-kaigaramushi]

Dactylopius azaleae Tinsley 1898: 319.

Pseudococcus azaleae (Tinsley 1898); Fernald 1903: 88 (change of combination).

Pseudococcus taxi Kanda 1943: 51. (synonymy by Kawai 1980: 109).

Crisicoccus azaleae (Tinsley 1898); Ferris 1953: 305 (change of combination); McKenzie 1967: 125; Kawai 1980: 109; Kawai 2003: 314; Danzig & Gavrilov-Zimin 2015: 200.

Planococcus azaleae (Tinsley 1898); Ezzat & McConnell 1956: 63 (change of combination).

Crisicoccus taxi (Kanda 1943); Kawai 1972: 6 (change of combination).

Material examined. Japan: Tokyo, Akikawa-shi, Nobe, on Rhododendron amagianum, 5.viii.1972, coll. S. Kawai, 3 adult females mounted singly and 2 adult females mounted together on a slide (KTUA); Ibaraki Prefecture, Tsukuba, Kannon-dai, on Rhododendron x pulchrum, 21.iv.2021, coll. J. Tabata, 4 adult females mounted singly (2 ELKU, 2 EUMJ).

Updated description

Appearance in life. Adult female 3‒4 mm long, dark purple to purple-brown, covered with a white powdery wax. Projections of wax secretion from body margin short and indistinct on cephalothorax, slightly longer on a few segments of posterior part of body. Body contents of this species turn blue-black to dark green in 10% potassium hydroxide solution (Kawai 1980, translated by HT).

Slide-mounted adult female (Fig. 4) (n = 9). Body elongate oval, 1.9–3.1 mm long and 0.9–1.9 mm wide; derm membranous; segmentation recognizable but not well developed. Anal lobes well developed, ventral surface with an anal lobe bar and a long apical seta, 154–239 µm long. Antenna 334–432 µm long, with 8 segments and many flagellate setae; subapical segment with 1 fleshy seta, apical segment with 3 fleshy setae. Eyespot present on margin, not associated with discoidal pores. Legs well developed, with many flagellate setae; hind leg measurements (in µm): trochanter + femur 248–320 long; hind tibia + tarsus 283–350; claw 26–36, without a denticle. Ratio of lengths of hind tibia + tarsus to trochanter + femur about 1: 1.04–1.16; ratio of lengths of hind tibia to tarsus 1: 1.79–2.40. Paired setose tarsal digitules present, subequal in length to the minutely knobbed claw digitules. Hind coxa with translucent pores on both surfaces; hind tibia sometimes with translucent pores on posterior surface; hind trochanter, femur and tarsus without translucent pores. Labium 120–152 µm long, shorter than clypeolabral shield. Circulus usually oval but rarely quadrate, located between abdominal segments III and IV or rarely on abdominal segment IV, usually divided by an intersegmental line, 40–113 µm long and 84–120 µm wide. Ostioles present, each with inner edges of lips weakly sclerotized; anterior ostioles each with a total for both lips of 17–29 trilocular pores and 2–7 setae; each posterior ostiole with a total for both lips of 16–44 trilocular pores and 4–7 setae. Anal ring 84–112 µm wide, bearing 6 setae, each seta 104–160 µm long. Cerarii numbering 6–12 pairs, normally present on posterior abdominal segments, rarely present also on thoracic segments. Anal lobe cerarii (C 18) each containing mostly 2 (rarely 3) conical cerarian setae, each 14–22 µm long and about 5–7 µm wide at base; 3–6 auxiliary setae, and a concentration of trilocular pores. Penultimate cerarii (C 17) each containing 2 conical setae, 0 auxiliary setae and a few trilocular pores. Cerarii situated further forward generally each with 2 conical cerarian setae and a few trilocular pores.

Dorsum. Setae spiniform, mostly straight, each 7–30 µm long, usually distributed segmentally; longest setae present on head or posterior abdominal segments. Trilocular pores each 3–4 µm wide, evenly distributed. Oral rim tubular ducts and oral collar tubular ducts absent. Discoidal pores each about 2 µm wide, sparsely distributed.

Venter. Setae relatively long and flagellate, each 11–140 µm long; setae on head longest. Multilocular disc pores, each 6–9 µm wide, present in medial areas of abdominal segments IV‒IX, arranged in single rows on each posterior area of abdominal segments IV‒V, 2 or 3 rows on each posterior area of abdominal segments VI–VII, and in a single row on each anterior area of abdominal segments VI–VII but arranged randomly on abdominal segments VIII and IX. Trilocular pores, each of same size as those on dorsum, evenly distributed. Oral collar tubular ducts all of 1 size, each about 2–4 µm wide, present on medial areas of abdominal segments IV–VII and usually forming transverse bands across segments; also relatively slightly stouter tubular ducts present on submarginal to marginal areas of abdominal segments I–VIII and thoracic segments. Discoidal pores, same width as those on dorsum, sparsely present.

Host plants in Japan. Ebenaceae: Diospyros kaki (Kawai 1980; 2003); Ericaceae: Rhododendron amagianum (Kawai 1980), Rhododendron macrosepalum (Kawai 1980), Rhododendron spp. (Kawai 2003), Rhododendron x pulchrum; Fabaceae: Albizia julibrissin (Kawai 1980); Fagaceae: Castanopsis cuspidata (Kawai 1980); Magnoliaceae: Magnolia kobus (Kawai 1980); Oleaceae: Ligustrum lucidum (Kawai 1980; 2003); Rosaceae: Eriobotrya japonica (Kawai 1980; 2003), Pyracantha angustifolia (Kawai 1980), Pyrus pyrifolia var. culta (Kawai 1980; 2003); Sapindaceae: Acer buergerianum (Kawai 1980; 2003); Schisandraceae: Illicium anisatum (Kawai 1980); Salicaceae: Salix babylonica var. babylonica (Kawai 1980); Taxaceae: Cephalotaxus harringtonia (Kanda 1943), Taxus cuspidata (Kawai 1980).

Remarks. Crisicoccus azaleae is similar to C. pini (Kuwana 1902) in having a small number of cerarii (<13 pairs) and oral collar tubular ducts of one size only. However, it differs from C. pini in the following morphological characteristics (contrasting characteristics of C. pini are given in parentheses): (i) a circulus usually present between abdominal segments III and IV on the venter (circulus always lacking); (ii) presence of spiniform and mostly straight dorsal setae (dorsal setae are mostly flagellate and slightly curved); and (iii) thoracic segments with a few ventral oral collar tubular ducts (thoracic segments without ventral oral collar tubular ducts). In particular, C. azaleae is characterized by straight, spiniform dorsal setae, which are significantly different from the curved flagellate setae in C. pini. Danzig & Gavrilov-Zimin (2015) stated that “ Crisicoccus azaleae (Tinsley 1898) is very similar, probably conspecific with C. pini ”. However, both species are clearly different and are treated here as wellseparated species.