Asterochiton rotundifoliae, Martin, 2020

Martin, Nicholas A., 2020, Revision of the whitefly genus, Asterochiton Maskell (Hemiptera: Aleyrodidae) from New Zealand, a study of intraspecific variation, Zootaxa 4859 (3), pp. 301-341 : 333-336

Asterochiton rotundifoliae sp. n.

Figures 12 A–L

Diagnosis. Usually 2 pairs of large discal (thoracic and abdomen1) and 8–9 pairs of large lateral discal setae about 100 µm.

Puparium ( Figs. 12 A–F). Oval; unpigmented; found on undersurface of leaves; widest at abdominal segments II & III; emarginated at thoracic and caudal tracheal pores; thin marginal layer of wax. Length 1.17 mm, 11 paratypes, 1.11–1.40 mm (mean 1.23); width 0.81 mm, paratypes, 0.72–1.07 mm (mean 0.86). Caudal and thoracic tracheal pores narrowly invaginated with 2–4 teeth ( Figs. 12 I–J). Margin finely crenulated ( Figs. 12 I–J), 9–12 crenulations in 0.1 mm .

Dorsum. Finely sculptured verging to linear markings marginally ( Figs. 12B, 12J ). Submargin width 60 µm with denser marginal crenulations 40 µm. Cephalothoracic (pro-, meso- & metathoracic) and abdominal depressions conspicuous. Abdominal segment VII median length, 35 µm, paratypes 30–38 µm (mean 34), about half the median length of segment VI ( Fig. 12G ). Transverse moulting sutures extending into subdorsum. Pro-mesothoracic and meso-metathoracic sutures, and abdominal segmentation prominent, reaching subdorsal area, and pro-mesothoracic sutures broken by depressions. Small pores on dorsal disc and submargin. Vasiform orifice located anterior of caudal tracheal opening by almost two times its own length. Caudal furrow present and well defined.

Vasiform orifice ( Fig. 12H ). Subtriangular; length 90 µm, paratypes, 75–93 µm (mean 86), width 65 µm, paratypes 55–68 µm (mean 63); open posteriorly, floor reticulated; operculum sub-trapezoidal, covering nearly half the length of orifice, length 38 µm, paratypes, 30–38 µm (mean 35), width 48 µm, paratypes 45–50 µm (mean 48); lingula exposed, not reaching beyond posterior margin of the vasiform orifice, terminal end slightly expanded and rounded, length 38 µm, paratypes 33–45 µm (mean 39), two subapical setae, 23 µm, paratypes 15–23 (mean 19).

Venter. Thoracic and caudal tracheal folds. Stipples present in thoracic fold and a different kind of stippling in the caudal fold. Legs and antennae present, a tiny seta on the basal and terminal segments of legs 2 and 3 ( Fig. 12J ). Ventral setae 13 µm, paratypes 13–38 µm, distance apart 63 µm, paratypes 63–83 µm; near to and posterior to anterior margin of vasiform orifice. Adhesive sacs present. Anterior abdominal spiracles on abdominal segment II, posterior spiracles present.

Chaetotaxy. First Cephalothoracic setae 108 and 125 µm, paratypes 5–150 µm (mean 92), first abdominal setae, 113 µm, paratypes 83–113 µm (mean 95), eighth abdominal setae, 8 µm, paratypes 5–8 µm (mean 6), setae anteriad of vasiform orifice; 8 pairs of cephalothoracic lateral setae, cephalothoracic lateral setae 2, 6 & 8 always on subdorsum, 100–125 µm, cephalothoracic lateral setae 1, 3, 4, 5 & 7, variable in length e.g. cephalothoracic setae 1, 2.5–100 µm, submarginal cephalothoracic setae 7 posterior to thoracic pore, cephalothoracic setae 4 usually discal or more rarely submarginal; abdominal lateral setae 2 submarginal, at 2 sites 2.5 µm, at the 3 rd site 63 µm, abdominal lateral setae 4–7 always on subdorsum, 75–125 µm, paratypes 50–138 µm, abdominal lateral setae 8 submarginal, 5 µm, at one site, the seta on one side was larger, 38 µm; caudal setae, 93 and 100 µm, paratypes 58–100 µm (mean 78); anterior marginal setae 5 µm, paratypes 5–13 µm (mean 9); posterior marginal setae 15 µm, paratypes 13–25 µm (mean 16).

Material examined. Holotype: New Zealand, NN, Eves Bush , 18 Apr 2004 (correct date, 17 April 2004), NA Martin, Coprosma rotundifolia leaves (slide 04-143a) ( NZAC02003147 ), furthest from data label.

Paratypes. 1 puparium, same slide as Holotype; 5 puparia ( NZAC 02015601 slide 04-143b), same data as Holotype; 5 puparia (slide 01-157), MC, Banks Peninsula, Hinewai Reserve, 21 Aug 2001, NA Martin, Coprosma rotundifolia underside of leaves; 5 puparia (slide 06-261), MC, Banks Peninsula, Prices Valley Reserve, 30 Apr 2006, NA Martin, Coprosma rotundifolia underside leaves ( NZAC 02005700).

Other specimens examined: 5 puparia (slide 01-190), MC, Banks Peninsula, Hinewai Reserve, 1 Nov 2001, NA Martin, Coprosma rotundifolia underside leaves; 1 larva /puparium (slide CFA _D_0508_037), MC, Banks Peninsula, Prices Valley, QE II Reserve, 17 August 2005, NA Martin, Coprosma rotundifolia ; 2 puparia, (slide NAM1909C), AK, Hunua Range, Hunua Falls, lower track, 19 September 2019, NA Martin, Coprosma rotundifolia .

All specimens deposited in NZAC (Auckland, New Zealand) .

Host plant. The only known host plant is Coprosma rotundifolia A.Cunn. (Rubiaceae) .

Distribution. The species was found in Nelson, Waimea plains, Eves Valley Scenic Reserve; Canterbury, Banks Peninsula, Prices Valley Reserve and Hinewai Reserve; Auckland, Hunua Ranges, Hunua Falls.

Etymology. The new species is named after its host plant.

Remarks. The specimens of this species show the typical variation of setae found between the two sides of a puparium and variation between specimens at the same location. However, this species also shows distinct variation between the three sites in the South Island from which adequate specimens are available. The basic arrangement of setae is found at Eves Bush, Nelson where only one of the cephalothoracic lateral setae may be large or tiny ( Fig. 12D ). At the other extreme all specimens from Prices Valley Reserve, Canterbury have at least four more large cephalothoracic lateral setae, with some specimens with all lateral setae large, including Abdominal lateral 8 ( Fig. 12F ). Specimens from Hinewai Reserve, Canterbury are in between the other two sites ( Fig. 12E ). The two Auckland specimens are most like those from Eves Bush, Nelson.

Figures

FIGURE 12. Asterochiton rotundifoliae n. sp. Holotype A–B, G–L. A. Dorsum line drawing, B. Puparium slide mount, C. puparium from which adult has emerged, D. Dorsum, variation of setae at Eves Bush Reserve, Nelson, E. Dorsum, variation of setae at Hinewai Reserve, Banks Peninsula, Canterbury, F. Dorsum, variation of setae at Prices Valley Reserve, Banks Peninsula, Canterbury. G. Abdominal segments VI, VII, VIII and vasiform orifice, H. Vasiform orifice, I. Caudal pore, caudal setae and posterior marginal seta. J. Thoracic pore, K. Tiny eighth abdominal lateral seta (arrow) and posterior marginal seta, L. Antenna and legs.