Paracoccus gillianwatsonae Zhang, 2024

Zhang, Jiang-Tao, Li, Chao-Qun, Liu, Xing-Ping & Wang, Yan, 2024, Two new species of the mealybug genus Paracoccus from Jiangxi, South China (Hemiptera, Coccomorpha, Pseudococcidae), ZooKeys 1197, pp. 1-11 : 1

Paracoccus gillianwatsonae Zhang sp. nov.

Figs 1 , 2

Materials examined.

Holotype: 1 ♀ (mounted singly on a slide), China, Jiangxi, Yichun City, Fengxin County, Chi'an Town [28°39′55″N, 115°21′9″E] / on the needles of Pinus massoniana Lamb. ( Pinaceae ) / 22.ix.2022, coll. Jiang-tao Zhang (CFJAU) . Paratypes: 4 ♀♀ (mounted singly on 4 slides), same data as holotype (3 CFJAU, 1 SWFU) .

Etymology.

The species is named after Dr Gillian W. Watson (Department of Life Sciences, the Natural History Museum, London, U.K.), who has selflessly helped the first author.

Description.

Live adult female (Fig. 1 ). Body elongate-oval, covered with thin, pale grey, mealy wax and with short, white lateral filaments around posterior body margins; these becoming successively longer on posteriormost four segments, with caudal filaments longest, each about 1/3 as long as maximum body width.

Slide-mounted adult female (Fig. 2 , n = 5). Body elongate-oval, 1.4-1.8 mm long and 0.8-1.0 mm wide. Anal lobes moderately developed, dorsal surface of each lobe with a small, slightly sclerotized area; ventral surface with long apical seta, each 180-200 µm long, and anal lobe bar present forwards from apical seta. Antennae each usually with 8 segments, sometimes with segments IV and V combined; each antenna 322-360 µm long, length of segments (in µm): I 35.0-37.5, II 42.5-47.5, III 42.5-50.0, IV 25.0-30.0, V 22.5-30.0, VI 30.0-37.5, VII 35.0-40.0 and VIII 85.0-95.0. Eye spot located on body margin lateral to antennal base. Clypeolabral shield 150-163 µm long and 120-140 µm wide. Labium 130-148 µm long and 80-95 µm wide, 0.87-0.98 times as long as clypeolabral shield. Legs well developed; claw stout, without a denticle; both tarsal digitules and claw digitules apically knobbed, longer than claw; with translucent pores present on hind coxa and tibia (Fig. 2D, E ). Hind leg measurements (in µm): coxa 55-65, trochanter + femur 227-245, tibia + tarsus 242-278, claw 20.0-22.5. Ratio of lengths of hind tibia + tarsus to trochanter + femur 1: 1.10-1.19, ratio of lengths of hind tibia to tarsus 1: 1.67-1.85. Circulus nearly quadrate, 50-75 µm long and 65-85 µm wide, situated between abdominal segments III and IV, divided by an intersegmental line. Anterior and posterior ostioles present, each lip with 7-12 trilocular pores and 0-4 setae. Anal ring 65-80 µm wide, bearing 6 long setae, each seta 112-130 µm long. Cerarii usually numbering 6 or 7 pairs on abdomen, sometimes also with 1 pair present on thorax and 1 pair present on head. Anal lobe cerarii (C18) (Fig. 2H ) each bearing 2 conical setae, each seta 15-17 µm long and 6-7 µm wide at base, with 1 or 2 auxiliary setae and 10-12 trilocular pores, all situated on a small slightly sclerotized area. Other cerarii each containing 2 conical setae and 3-5 trilocular pores. Cerarii C12, if present, usually each containing only 1 conical seta and 1 short seta. Cerarii on thorax, if present, usually each containing 2 slender conical setae. On head, usually the ocular cerarii (C3) present, each containing 3 or 4 slender setae. Discoidal pores (Fig. 2C ), each narrower than a trilocular pore, scattered on dorsum and venter.

Dorsum. Setae (Fig. 2I ) short, stiff, sometimes spine-like, mostly each 20.0-32.5 μm long, accompanied by shorter setae, each 7.5-15.0 µm long; setal bases not closely associated with trilocular pores. Trilocular pores (Fig. 2B ), each 3.0-3.5 µm wide, evenly distributed. Oral rim tubular ducts (Fig. 2J ) present, numbering 11-24 in total, each duct 11-12 µm long and about 4 µm wide, with rim 8-9 µm in diameter, usually present singly near margins of head, thorax, and close to cerarii on posterior abdominal segments, and others usually present in medial or submedial areas of thorax and abdominal segments II and III, or only on abdominal segment II.

Venter. Setae relatively long and flagellate, longest setae present on medial area of head and posterior abdominal segments, each 62.5-125.0 µm long, accompanied by shorter setae, each 20.0-32.5 µm long. Cisanal setae each 50-55 µm long; obanal setae each 45-50 µm long. Trilocular pores similar to those on dorsum, evenly distributed. Multilocular disc-pores (Fig. 2G ), each 7-8 µm in diameter, present around vulva in more-or-less single rows at posterior edges of abdominal segments IV-VII, and scattered or in rows at anterior edges of abdominal segments VI-VII, sometimes with 2 pores on abdominal segment III; also sparsely present on margins of posterior abdominal segments, and occasionally in submedial areas of thorax. Oral collar tubular ducts of 2 main sizes present: larger type (Fig. 2A ), each 6-7 µm long and about 3.5 µm wide, present on medial areas of abdominal segments III-VII, in marginal groups on all abdominal segments and opposite each anterior coxa; and smaller type (Fig. 2F ), each 5-6 µm long and 2.0-2.5 µm wide, present on medial areas of abdominal segments III-VII, also sparsely present in marginal areas together with large ducts, and occasionally present in medial areas of thorax.

Host plant.

Pinaceae : Pinus massoniana Lamb.

Distribution.

China (Jiangxi).

Remarks.

Paracoccus gillianwatsonae sp. nov. is similar to P. burnerae (Brain, 1915) (morphological characteristics of P. burnerae based on the redescription and illustration by Williams (2004)) in having ventral multilocular disc-pores in single rows at the posterior edges of abdominal segments IV and V; it differs from the latter (character states of P. burnerae given in parentheses) by having: (i) ventral oral collar tubular ducts absent from margins of the head (present); (ii) cerarii numbering fewer than 18 pairs (18 pairs); and (iii) translucent pores absent from hind femur (present).

Figures

Figure 1. Live adult female of Paracoccus gillianwatsonae Zhang, sp. nov. on a needle of Pinus massoniana Lamb. (Pinaceae).

Figure 2. Adult female of Paracoccus gillianwatsonae Zhang, sp. nov. A large-type oral collar tubular duct B trilocular pore C discoidal pore D hind coxa E hind tibia F small-type oral collar tubular duct G multilocular disc-pore H anal lobe cerarius (C 18) I dorsal seta J oral rim tubular duct.