Planococcus camelliae Zhang, 2023

Zhang, Jiangtao & Deng, Jun, 2023, A study of the mealybug genus Planococcus Ferris, 1950 from China, with description of a new species (Hemiptera, Coccomorpha, Pseudococcidae), ZooKeys 1178, pp. 77-95 : 77

Planococcus camelliae Zhang sp. nov.

Figs 1 , 2 , 3

Material examined.

Holotype: China: 1 ♀ (mounted singly on a slide), Jiangxi Province, Fuzhou City, Le’an County, Jinzhu she minority Township , Pingxi Village [27°06'N, 115°56'E], on Camellia oleifera ( Theaceae ), 5.x.2019, coll. Jiang-tao Zhang (CFJAU) . Paratypes: 4 ♀♀ (mounted on 4 slides), same data as holotype (2 CFJAU, 2 SWFU) ; 6 ♀♀ (mounted on 6 slides), same collection and host plant as holotype, 4.viii.2018, coll. Jiang-tao Zhang (4 CFJAU, 2 SWFU).

Other material examined.

1 ♀ (mounted on 1 slide), same data as holotype (CFJAU) ; 8 ♀♀ (mounted on 7 slides), same collection and host plant as holotype, 4.viii.2018, coll. Jiang-tao Zhang (CFJAU).

Description.

In life body oval, covered in white mealy wax, with ~ 18 pairs of short lateral filaments around body margin, found inside ant nests or tents on Camellia oleifera branches and fruits (Fig. 1 ).

Body of adult female on microscope (Fig. 2 ) oval, 1.40-3.98 mm long and 0.85-2.39 mm wide. Anal lobes developed, each ventral surface with an apical seta 187-275 μm long, and a well-developed anal lobe bar. Antennae 8-segmented, each 336.5-427.5 μm long, lengths of segments: I 40-50, II 40-52.5, III 42.5-60, IV 20-40, V 22.5-44, VI 30-36.5, VII 37.5-42.5, VIII 87.5-107.5 μm. Clypeolabral shield 142.5-167.5 μm long, 112.5-137.5 μm wide. Labium 131.5-157.5 μm long, 60-75 μm wide. Legs well developed, slender; hind coxa 60-84 μm long, hind trochanter + femur 202.5-277.5 μm long, hind tibia + tarsus 241.5-327.5 μm long; claw 20-25 μm long, both tarsal digitules and claw digitules knobbed, longer than claw. Ratio of lengths of hind tibia + tarsus to hind trochanter + femur 1: 1.11-1.19. Ratio of lengths of hind tibia to tarsus 1: 1.64-2.29. Translucent pores present on hind coxa and tibia. Circulus present, nearly square, 55-112.5 μm long and 50-71.5 μm wide, divided by an intersegmental line. Both anterior and posterior ostioles present, each lip with 7-22 trilocular pores and 1-5 setae. Anal ring 60-85 μm wide, bearing six long setae, each 105-150 μm long. Cerarii numbering 18 pairs. Anal lobe cerarii (C18) each bearing two conical setae, each seta 20-24 μm long, accompanied by 2-5 auxiliary setae and 15-25 trilocular pores, situated on a small slightly sclerotised area. Other cerarii, sometimes situated on small prominences, each bearing two conical setae, occasionally only with one conical seta, but ocular pairs (C3) sometimes with three conical setae, all cerarian setae conical and with flagellate tips, accompanied by 4-10 trilocular pores. Discoidal pores smaller than the trilocular pores, sparsely but evenly distributed.

Dorsum. Setae stout, moderate length and with flagellate tips (Fig. 3 ), sometimes with one or two trilocular pores next to setal bases, each 20-32.5 μm long. Trilocular pores present, each 3-4 μm in diameter, evenly distributed. Oral collar tubular ducts present and without apparent rims, each 8-10 μm long, 3-4 μm wide, in small marginal groups around posterior abdominal segments, usually 1 duct adjacent to some abdominal cerarii, occasionally also present on median areas of abdominal segments. Multilocular disc pores absent.

Venter. Setae flagellate, longer seta each 75-142.5 μm long. Cisanal setae 50-70 μm long, shorter than anal ring seta. Trilocular pores similar to those on dorsum, evenly distributed. Oral collar tubular ducts of two main sizes: the small type, each 6-7 μm long, 2 μm wide, mainly distributed across middle of abdominal segments II-VII, also a few occurring on median areas of thorax and intermixed with marginal ducts; the large type, similar to those on dorsum, present in transverse rows across abdominal segments III-VII, also in marginal groups around head, thorax, and abdomen, but absent from opposite each postocular cerarius (C4). Multilocular disc pores each 8-9 μm in diameter, around vulva, in single or double rows across posterior edges of abdominal segments VII, in single rows across posterior edges of abdominal segments IV-VI, scattered or in single rows across anterior edges of abdominal segments IV-VII or V-VII, sometimes 1-4 pores also on abdominal segment III, a few pores sometimes scattered over median areas of the thorax and head, pores entirely absent from margins of abdominal segments.

Host plant.

Theaceae : Camellia oleifera .

Distribution.

China (Jiangxi).

Remarks.

Planococcus camelliae sp. nov. is similar to P. kraunhiae by having oral collar tubular ducts present on dorsum, but it differs from the latter by the following features (condition of P. kraunhiae given in parenthesis): (i) multilocular disc pores absent from margins of abdominal segments (present on margins); (ii) single dorsal oral collar tubular ducts usually adjacent to some abdominal cerarii (in groups of 2-5 next to some abdominal cerarii); (iii) dorsal oral collar tubular ducts usually similar in size to the large ducts on venter (usually larger than those on venter). The new species also resembles the type of P. citri with oral collar tubular ducts present on dorsum, but it differs from the latter by the following features (condition of P. citri given in parenthesis): (i) multilocular disc pores absent from margins of abdominal segments (present on margins); (ii) dorsal setae stout and with flagellate tips (usually flagellate); (iii) dorsal oral collar tubular ducts usually similar in size to the large ducts on venter (if present, usually larger than those on venter).

The pairwise genetic divergences (by K2P distance) in COI among these six specimens (of five species) are listed in Table 1 . The K2P distance is 0.00% within P. camelliae , 10.44-12.21% between P. camelliae and other four Planococcus species list. In mealybugs, the interspecific variation in COI is 11.53% (1.96-19.48%) ( Wang et al. 2016), and therefore, our molecular data confirms P. camelliae as a distinct species.

Etymology.

The species epithet is derived from the generic name of its host plant, Camellia .

Figures

Figure 1. Planococcus camelliae Zhang, sp. nov.: A an ant carton that harbours mealybugs inside B mealybugs found inside ant carton with tending ants.

Figure 2. Adult female of Planococcus camelliae Zhang, sp. nov.: A Large oral collar tubular duct B trilocular pore C discoidal pore D hind coxa E hind tibia F claw G small oral collar tubular duct H multilocular disc pore I anal lobe cerarius (C 18) J anal ring K large dorsal seta L small dorsal seta M cerarius on head.

Figure 3. Dorsal setae on Planococcus camelliae Zhang, sp. nov.: A small seta B large seta with trilocular pore next to setal base C large seta without trilocular pore next to setal base.