Acizzia keithi, Taylor, Gary S. & Moir, Melinda L., 2009

Taylor, Gary S. & Moir, Melinda L., 2009, In threat of co-extinction: two new species of Acizzia Heslop-Harrison (Hemiptera: Psyllidae) from vulnerable species of Acacia and Pultenaea, Zootaxa 2249, pp. 20-32 : 27-29

Acizzia keithi , sp. nov.

( Figs 11–19 ; Tables 1 –5)

Types. AUSTRALIA, New South Wales: Holotype: 1 3 (slide), Cataract Falls, Blue Mountains, 647 m, 33°43.832’S, 150°26.566’E, M.L. Moir & K.E.C. Brennan, 15.i.2007, ex Pultenaea glabra (ASCU ASCT00024950). Paratypes: 2 Ƥ (slide), 1 Ƥ (dried), same data as holotype (ASCU ASCT00024951- 00024953); 2 Ƥ (slide), 1 Ƥ (dried), same data, except 16.i.2008 (WINC 030558 - 030560); 2 Ƥ (dried, on 1 point), same data (MLM 00838-00839).

Description. Adult. Head, habitus and wing as in Figs 11–16 . Colouration: General colour dark orangebrown with ochraceous to brown markings (female similar to male). Head and thorax dark orange-brown; vertex dark orange-brown, with 1+1 indistinct brown spots posterior to submedial foveae and confluent with hind margin of vertex; genal processes dark orange-brown with brown infuscation at apex; antennal segments 1–2 dark orange-brown; segments 3–8 ochraceous with progressively darker apices; segments 9–10 dark brown; pronotum dark orange-brown with 1+1 brown submedial spots; mesopraescutum orange-brown with 1+1 indistinct broad triangular brown markings anteriorly; mesoscutum orange-brown with 2+2 light brown longitudinal submedial stripes; mesoscutellum orange-brown; abdominal tergites and sternites orange-brown; meracanthus orange-brown; legs ochraceous with dorsal dark brown longitudinal infuscation on femur and tibia; tarsi ochraceous; apices of distal segments of tarsi with brown infuscation; forewings heavily pigmented with dark brown to black maculation; wing veins brown. Male proctiger, subgenital plate and parameres ochraceous. Female proctiger and subgenital plate ochraceous, merging to dark brown at apices.

Structure: Male: Antenna short, 1.0–1.2 times width of head, 10-segmented, a single subapical rhinarium on each of segments 4, 6, 8 and 9; segment 10 with 2 long, pointed apical setae; genal processes short, broad, truncate, ventrad, declined ca. 30° to longitudinal axis of vertex, ca. 80° to longitudinal axis of body, delineated from anterior margin of vertex by weak suture; vertex flat with weak medial suture and 1+1 indistinct foveae; pronotum short, broad, with hind margin little recurved; thorax strongly arched, head little wider than pronotum, about same width as mesoscutum; forewing short, ovate with broadly rounded apex; Rs moderate in length, terminating anterior of wing apex; vein m1+2 terminating at wing apex; cell m1 long, triangular; cell cu1 elongate triangular, strongly recurved towards wing base; radular areas not seen; meracanthus conical, pointed; apical metatibia with 1 outer and 4 inner spurs, basitarsus with a pair of apical spurs. Male terminalia as in Figs 17–18 ; proctiger high, narrow with narrow, elongate lateral expansions without terminal distal appendages; parameres thin, elongate, evenly curved inward towards thin apex; hind margin of parameres with inconspicuous basal node; inner face of parameres with short rod-shaped setae in a medial field and a short blunt, triangular node at basal third; apical segment of aedeagus thin, with littleexpanded apex. Female: terminalia as in Fig. 19 ; proctiger and subgenital plate elongate triangular from lateral aspect.

Nymph. Unknown.

Comments. A total of 140 individuals of other plant species, including Acacia longifolia and A. ulicifolia ,, known hosts of A. acaciaedecurrentis (Froggatt) , A. acaciaejuniperinae (Froggatt) , A. conspicua (Tuthill) and A. frenchi (Froggatt) ( Hollis 2004) , were sampled in the immediate vicinity of the Pultenaea glabra population, but failed to yield any specimens of A. keithi . Therefore, although nymphs were not detected on P. glabra , there was little possibility that the specimens were from plant species other than this host at this location (Moir, unpublished data).

Acizzia keithi sp. n. can be distinguished from all other species of Acizzia by the following suite of characters: antenna short, 1.0–1.2 times width of head ( Fig. 11 ); genal processes short, 0.23–32 times length of vertex, with broad, blunt apices ( Fig. 11 ); both sexes with characteristically mottled wings ( Figs 12–16 ); male proctiger with thin, erect apical node and broadly-triangular lateral (posterior) lobes without terminal distal appendages ( Fig. 17 ); apical segment of aedeagus thin, with little-expanded apex ( Fig. 17 ); hind margin of parameres with inconspicuous basal node ( Fig. 17 ); inner face of parameres with short rod-shaped setae in a medial field, and a short blunt, triangular node at basal third ( Fig. 18 ); female terminalia long, proctiger and subgenital plate elongate triangular from lateral aspect ( Fig. 19 ).

Etymology. Named in honour of Dr David Keith, who suggested Pultenaea glabra as a good candidate to search for co-threatened insects, and provided financial, logistical and intellectual support to ensure this sampling was possible. This ultimately led to the discovery of the new Acizzia species.

Host-plant association. Pultenaea is a new generic host record for Acizzia , indeed for any Psylloidea. The genus Pultenaea is endemic to Australia with 116 species ( Orthia et al. 2005). It is mainly confined to shrublands or woodlands of south-western and eastern Australia, and is absent from arid or tropical regions ( Orthia et al. 2005). The recorded host species, Pultenaea glabra , is an erect shrub to 3 m and is often associated with swamps or damp depressions in highland country (700–2200 m above sea level) (de Kok & West 2002). Pultenaea glabra is nationally listed as ‘vulnerable’ and the key threatening processes are inappropriate fire regime, dieback disease (caused by Phytophthora cinnamomi ), and habitat clearing ( Fraser et al. 2004). It has a disjunct distribution along the east coast of Australia with the largest populations in the central and northern tablelands of New South Wales, but restricted populations also occur in the Dandenong Range of Victoria, and a single population has been recorded from the central coast of Queensland (CHAH 1995-2002; de Kok & West 2002; Fraser et al. 2004). Therefore, it is possible that additional populations of Acizzia keithi will be discovered with further sampling of these disjunct host populations, although we point out that a search of other entomological collections (e.g., NSW Department of Primary Industries, Australian National Insect Collection, Australian Museum, Western Australian Museum, etc) failed to yield additional specimens from other localities. Alternatively, the insect assemblage may change across the range of P. glabra , and A. keithi may only occur in the one locality (see Andrew & Hughes 2005 for examples of assemblages of Hemiptera changing along such a latitudinal gradient). Other host associations recorded on Pultenaea glabra include seed predators within the beetle family Bruchidae ( Auld 1991) , and other sapfeeders, lacebugs within the genus Radinacantha (Moir, in press), although no host-specific association has been documented to date.

Figures

FIGURES 11 – 16. Acizzia keithi, sp. nov. (11), Head, male, (dorsal aspect, slide); (12), habitus, male, (dorsal aspect); (13), habitus, female, (dorsal aspect); (14), habitus, male (lateral aspect); (15), habitus, female (lateral aspect); (16), forewing, male. Scale = 0.5 mm.

FIGURES 17 – 19. Acizzia keithi, sp. nov. (17), Male terminalia (lateral aspect); (18), paramere (inner face, lateral aspect); (19), female terminalia, (lateral aspect). Scale = 0.2 mm.