Myotrioza insularis Taylor

Taylor, Gary S., Fagan-Jeffries, Erinn P. & Austin, Andy D., 2016, A new genus and twenty new species of Australian jumping plant-lice (Psylloidea: Triozidae) from Eremophila and Myoporum (Scrophulariaceae: Myoporeae), Zootaxa 4073 (1), pp. 1-84 : 45-49

Myotrioza insularis Taylor , sp. nov.

( Figs 71–78 , 85–86 , 90 ; Tables 1–8 )

Types. AUSTRALIA, South Australia: Holotype: 1 ♂ (dried) Kangaroo Island, Mt Thisby, 35º50.622’S, 137º44.697'E, GS Taylor & E Kinnaird, 24.iii.2011, Swept Myoporum insulare, 2011 0 60 (KI60) ( SAM). Paratypes: 1 ♂, 3 ♀ (dried), 1 ♀ (ethanol), same data as holotype ( SAM, WINC); 3 ♂, 5 ♀, 4 immatures (slide) Urrbrae, Waite Campus, 34º58.22’S, 138º38.40'E, GS Taylor, 5.x.2001, on Myoporum insulare ( SAM, WINC); 2 ♂, 5 ♀ (dried), 4 ♂, 4 ♀ (slide), 8 ♀ (ethanol), Kangaroo Island, Eleanor River, 35º58.29’S, 137º12.11'E, GS Taylor, swept, 4.xii.2003, Myoporum insulare ( WINC); 7 ♂, 8 ♀ (dried), Pelican Lagoon CP, NE Kangaroo Island, RV Glatz, 4.x.2007, on blossoming Myoporum insulare , 7437 (RVG); 1 ♂, 2 ♀ (dried), same data except, near 35°48.034'S, 137°46.927'E, 4.x.2008, 9496 (RVG); 1 ♀ (ethanol), Port Lincoln, Point Boston Rd, 34°37.802'S, 135°55.663'E, GS Taylor, 6.x.2011, Swept Myoporum insulare, 2011 213 (PL3) ( WINC); 2 ♂, 8 ♀, 1 immature (ethanol), Yorke Peninsula, Coobowie, 35º03.290'S, 137º43.788'E, G.S. Taylor, 26.iv.2013, Swept, Myoporum insulare, 2013 0 12 ( WINC). Other material examined. South Australia: 1 ♂, Kingscote, 35º39.506’S, 137º38.268'E, DA Young, 31.viii.2009, on foliage of Beyeria lechenaultii , 9487 (RVG); 1 ♀ (dried), same data except 4.ix.2009, 9503 (RVG).

Description. Adult ( Figs 71–74 ). Colouration. Male: [specimens point-mounted with prior storage in ethanol] Pale yellow with brown infuscation and markings: vertex with brown infuscation, darker anteriorly and along medial suture; eyes greyish brown; antennal segments 8–10 progressively dark brown to almost black; pronotum with brown infuscation on posterior margin; mesopraescutum and mesoscutum with variable brown infuscation, in darker specimens with a pair of darker brown submedial markings on mesopraescutum and 3 pairs on mesoscutum; mesoscutellum variable from pale yellow to brown; fore and hind wings clear; fore wing veins equally pigmented brown; legs pale yellow-brown; abdominal tergites 1–5 pale yellow; abdominal membrane colouration pale green; proctiger, subgenital plate and parameres yellow-brown; apices of parameres dark brown. Female: [specimens mounted with prior storage in ethanol] as for male except infuscation and markings on vertex and thoracic segments paler; proctiger and subgenital plate pale yellow-brown with apices with brown infuscation.

Structure. Measurements as in Tables 4–8 . Body narrow, elongate ( Figs 71–74 ). Head ( Figs 75–76 ); vertex with prominent medial suture, deeply sunk in vicinity of fovea; genal processes short, 0.33–0.42 times as long as vertex; antenna short, 0.78–0.89 times width of head, with a single subapical rhinarium on each of segments 4, 6, 8 and 9; segment 10 with a long bluntly rounded seta and a short bluntly rounded seta. Fore wing ( Figs 77–78 ) 4.51– 5.36 times as long as head width, 2.70–3.17 times as long as wide, elongate with slightly pointed apex; vein Rs straight, slightly upturned distally, terminating well short of wing apex, considerably shorter than vein M, RsM: 0.73–0.82; medial cell smaller than cubital cell; veins M1+2 and M3+4 short, broadly diverging with corresponding low m1 cell value: 1.28–1.53; veins Cu1a long, arched and Cu1b long, each widely divergent with corresponding low cu1 cell value: 1.23–1.60; metatibia 1.07–1.13 times as long as width of head, considerably longer than metafemur, with 2 inner and 1 outer small, sclerotised apical spurs. Male terminalia ( Figs 85–86 ); proctiger conoid, without lateral lobes; subgenital plate broadly rounded; parameres ( Fig. 86 ) very short, narrow, blade-like, evenly tapering to incurved sclerotised apices; distal portion of aedeagus short, with asymmetrical apical expansion ( Fig. 85 ). Female terminalia ( Fig. 90 ): proctiger short, truncate with weakly sclerotised apex; subgenital plate short, triangular with tapering, weakly sclerotised apex; distal portion of proctiger with dense brush of short pale, darkly tipped setae and subgenital plate with sparse short setae.

Final instar immature. Triozine in type: dorsal surface outline broadly ovate (as in Fig. 123 ); cephalothorax entire; fore wing pad produced anteriorly to anterior margin of eye; abdominal tergites fused to form a caudal plate; caudal plate short, broad; circumanal pore field ventral and distant from posterior margin of abdomen; sectasetae short, closely and evenly spaced on anterior margin of head, fore and hind wing margins and margin of caudal plate; dorsum with evenly spaced short fine setae. Colouration (specimens in ethanol): pale yellow-green with mottled pale brown markings. Measurements and ratios (n=4): AL 0.34–0.36; HW 0.69–0.82; BL 2.29–2.59; BW 1.80–2.01; WL 1.22–1.45; CPL 1.04–1.19; CPW 1.27–1.47 CPRW 0.20–0.23; AL:HW 0.41–0.50; AL:WL 0.25– 0.28; HW:BL 0.30–0.32; BL:BW 1.27–1.36; CPL:CPW 0.75–0.82; CPRW:CPW 0.15–0.16.

Comments. Myotrioza insularis sp. nov. can be distinguished by the following unique combination of characters: habitus as in Figs 71–74 , antenna with normal arrangement of rhinaria, fore wing elongate with rounded apex, Rs considerably shorter than vein M ( Figs 77–78 ), female proctiger short with field of weakly hooked setae, rounded profile without terminal upward inflection, valvula ventralis curved, ventral profile of female subgenital plate curved ( Fig. 90 ), male proctiger conoid with lateral lobe, aedeagus short, paramere broadly ovate with rounded apex ( Figs 85–86 ).

Myotrioza insularis sp. nov. is most closely related to M. clementsiana sp. nov. (COI sequence divergence 7.4–8.1%) ( Table 1 ). They differ from all other species of Myotrioza gen. nov. by their elongate habitus and general pale yellow brown colouration with abdominal membrane colouration green. M. insularis sp. nov. differs from M. clementsiana sp. nov. in its larger body size, it occurs on M. insulare rather than M. platycarpum and has a coastal rather than an inland, eremean distribution. Within M. insularis sp. nov., sequence divergence of Kangaroo Island material from the proximal localities on Fleurieu, Yorke and Eyre Peninsulas on the South Australian mainland may be explained by genetic divergence by distance, separated by biogeographic barriers and consequential disjunct host populations ( Fig. 1 ).

Etymology. Named after L. insularis , referring to an island.

Host-plant association and distribution. ( Tables 2–3). Myotrioza insularis sp. nov. is recorded from Myoporum insulare R.Br. (Boobialla) on Kangaroo Island, southern Yorke Peninsula and southern Eyre Peninsula, and on an ornamental tree in suburban Adelaide on mainland South Australia. It is one of 10 species of Myotrioza gen. nov. and 24 species of Triozidae recorded for South Australia. It is considered endemic to that state, although it is likely to occupy a broad distribution given that its host is widely distributed in coastal southern Australia. It is one of 2 species of Myotrioza gen. nov., namely M. insularis sp. nov. and M. markmitchelli sp. nov. from M. insulare . Myoporum insulare is a shrub or small tree to 6 m high. It occurs commonly in sandy coastal heath in WA, SA, NSW, Vic, Tas ( Chinnock 2014). Its record from Beyeria lechenaulti is considered doubtful, being more likely to be vagrant from nearby plants.

Figures

FIGURE 1. Molecular phylogeny constructed from 427 bp region of the mitochondrial gene cytochrome c oxidase subunit I (COI) for the Myotrioza from Eremophila and Myoporum comprising a broad sampling of in-group and 5 out-group taxa. The number of putative species are shown for uncorrected pairwise percent divergences (Table 1) at 2 %, 3 – 5 %, 5 – 6 % and 8 %.

FIGURES 71 – 78. Myotrioza insularis, sp. nov. (71), habitus, male, (dorsal aspect); (72), habitus, female (dorsal aspect); (73), habitus, male (lateral aspect); (74), habitus, female (lateral aspect); (75), head, male (dorsal aspect, from slide); (76), head, female (dorsal aspect); (77), fore wing, male (from slide); (78), fore wing, female. Scale = 1.0 mm.

FIGURES 79 – 86. Figs 79 – 80: Myotrioza eremophili, sp. nov. (79), male terminalia (lateral aspect); (80), paramere (inner face, lateral aspect); Figs 81 – 82: M. flindersiana, sp. nov. (81), male terminalia (lateral aspect); (82), paramere (inner face, lateral aspect); Figs 83 – 84: M. gawlerensis, sp. nov. (83), male terminalia (lateral aspect); (84), paramere (inner face, lateral aspect); Figs 85 – 86: M. insularis, sp. nov. (85), male terminalia (lateral aspect); (86), paramere (inner face, lateral aspect). Scale = 0.2 mm for male terminalia, 0.1 mm for parameres.

FIGURES 87 – 90. Female terminalia (87), Myotrioza eremophili, sp. nov.; (88), M. flindersiana, sp. nov.; (89), M. gawlerensis, sp. nov.; (90), M. insularis, sp. nov. Scale = 0.5 mm (all at same scale).

FIGURES 123 – 124. Myotrioza markmitchelli, sp. nov. (123), immature (dorsal aspect); (124), anterior margin of head and lateral margin of fore wing pad showing sectasetae. Scale = 1.0 mm in Fig 123, 0.05 mm in Fig. 124.