Stevekenia aiea, Percy, Diana M., 2017

Percy, Diana M., 2017, A new endemic psyllid genus, Stevekenia gen. nov. (Hemiptera: Psylloidea, Triozidae), from the Hawaiian Islands with two new and rare species on threatened host plants in the endemic genus Nothocestrum (Solanaceae), Zootaxa 4286 (3), pp. 370-380 : 373-377

Stevekenia aiea sp. nov.

( Figs. 1 H–L; 2I –M,O,R; 3D–E,G,M–N,Q)

Adult colour. General body colour light brown, yellow-green on abdomen; with darker brown markings on thorax abdomen and legs. Fore wing membrane with an irregular band of light brown pigmentation across basal 3rd of the wing.

Adult structure as for generic description with the following species specific characters: Moderately long setae scattered on ventral fore wing margin, cell m2 with a single cluster of marginal radular spines towards the posterior margin of the cell, and radular spine clusters narrow, fore wing cell m2 and cu1 subequal in size (ratio HM:HCU <2), vein Cu1 ~ 0.5 length of vein R ( Fig. 1 H–I,L). Hind wing extremely short, length <2 mm, and ± 0.5 fore wing length ( Fig. 1 J). Moderately long setae on head, thorax, legs, and sternites of female abdomen. Head with vertex extensions as two small diverging projections ( Fig. 2 I–J). Antennae with a single, simple rhinarium apically on each of segments 4, 6, 8, 9, the length of longest seta on the terminal segment longer than segment 9. Hind tibia with small genual spine basally and less markedly stalked apical spurs (1+2) with the pair of spurs not or barely conjoined at the base ( Fig. 2 M,O,R). Male subgenital plate rounded posteriorly in lateral view, paramere with a short anteriorly directed apex, distal aedeagus segment slightly constricted medially with apical head smaller, blunt, and ~ 0.5 length of distal segment ( Fig. 3 D–E,G). Female subgenital plate more or less straight ventrally, and bluntly acute to acute apically ( Fig. 3 M).

Egg. Shorter pedicel <0.5 length of egg, and linearly ordered cellular outgrowths, tail slender without cellular outgrowths ( Fig. 3 Q).

Adult measurements (mm) and ratios. (1 male, 1 female) WL: 3.86–3.97; WW: 1.55–1.61; HW: 0.64–0.65; AL: 2.79; PB: 0.12–0.14; WL:WW: 2.47–2.50; WL:RsL: 2.91–3.11; CUR: 1.29; MR: 0.63–0.65; HM:HCU: 1.75– 1.89; HW:VW: 1.79–1.83; VL:VW: 0.17–0.25; AL:HW: 4.28–4.38; HW:HT: 0.88–0.90; HT:HF: 1.33–1.37. Male terminalia: MP: 0.25; PL: 0.20; AEL: 0.18; PL:HW: 0.31; MP:PL: 1.27; PL:AEL: 1.07; AEL:AELH: 2.09; PL:SH: 1.02. Female terminalia: FP: 0.65; FSP: 0.39; RL: 0.22; OVH: 0.07; EL: 0.28; EW: 0.09; FP:RL: 3.00; FP:HW: 0.99; FP:SP: 1.65; EL:EW: 3.18.

Immature. Unknown.

Host plant. Nothocestrum peltatum .

Distribution. This species is endemic to Kauai, and is only known from one location in Kokee State Park. The host plant is also endemic to Kauai.

Etymology. Named for the association with the host plant, the endemic Hawaiian genus Nothocestrum , using the Hawaiian name for the genus, Aiea (noun in the nominative case).

Comment. This species is mostly easily differentiated from S. nothocestri by the irregular band of light brown pigmentation across basal 3rd of the fore wing membrane, as well as other characters noted in comment under S. nothocestri and in the key.

Type material. Holotype male (slide mounted), Awaawapuhi Valley , Kokee State Park, Kauai, USA, ex Nothocestrum peltatum , 26 May 2002, “381-02” D. Percy leg. ( BMNH) . Paratype 1f (slide mounted), as for holotype (BMNH).

Gene sequences. GenBank KY971542 ( COI), KY971544 (cytB).

Figures

FIGURE 1. A – G Stevekenia nothocestri, H – L Stevekenia aiea. A—fore wing; B—hind wing; C—detail of fore wing cell m 2 indicating position of two clusters of marginal radular spines, inset illustrates disbursed distribution of spines; D—detail of long setae on fore wing ventral margin and veins; E—dorsum of thorax; F—female habitus (cluster of eggs in abdomen); Ghead and thorax; H—fore wing (male); I—fore wing (female); J—hind wing (female); K—detail of fore wing cells m 1 and m 2 indicating position of single clusters of marginal radular spines towards posterior in each cell, inset illustrates narrow distribution of spines; L—detail of long setae on fore wing ventral margin and veins.

FIGURE 2. A – H, N, P – Q Stevekenia nothocestri, I – M, O, R Stevekenia aiea. A—head (dorsal view above, ventral view below) indicating position of posterior eye rim extensions (outlined), lateral ocelli, and anterior vertex extensions (in dorsal view) and position of medial ocellus below vertex extensions (in ventral view); B—head (dorso-anterior view) indicating short vertex with anterior vertex extensions; C—head (ventro-anterior view); D—head (lateral view) indicating position of posterior eye rim extension; E—single disk rhinarium on antennal segment 6 (illustration inset); F—multiple disk rhinaria on antennal segment 4; G—head and antenna; H—proboscis; I—head (dorsal view above, ventral view below) indicating position of posterior eye rim extensions, lateral ocelli, and anterior vertex extensions (in dorsal view) and position of medial ocellus below vertex extensions (in ventral view); J—detail of diverging anterior vertex extensions; K—head and antenna; L—proboscis; M, N—hind leg; O, P—genual spine at base of hind tibia; Q—apical tibial spurs and tarsi; R—detail of pair of apical tibial spurs not conjoined basally; S—detail of hind tarsal claws and arolium.

FIGURE 3. A – C, F, H – L, O – P Stevekenia nothocestri, D – E, G, M – N, Q Stevekenia aiea. A—male terminalia; B—sperm pump with comparative size of paramere; C—aedeagus; D—male terminalia; E—aedeagus; F, G—paramere (external surface); H—female terminalia; I—female subgenital plate (ventral view); J—female proctiger (dorsal view); K detail of dorsum of female proctiger indicating position of raised pores flanking anal ring; L female abdomen (with eggs) indicating long setae on sternites; M—female terminalia (with egg) indicating position of raised pore flanking anal ring, inset illustration of anal ring shape and circumanal pores; N—ovipositor; O – Q—eggs indicating pedicel, tail, plug-like structure, and surface cellular outgrowths (illustrated).