Ctenarytaina bipartita, Burckhardt, Daniel, Farnier, Kevin, Queiroz, Dalva L., Taylor, Gary S. & Steinbauer, Martin J., 2013

Burckhardt, Daniel, Farnier, Kevin, Queiroz, Dalva L., Taylor, Gary S. & Steinbauer, Martin J., 2013, Ctenarytaina bipartita sp. n. (Hemiptera, Psylloidea), a new eucalypt psyllid from Southeast Australia, Zootaxa 3613 (6), pp. 589-596 : 590-594

Ctenarytaina bipartita sp. n.

( Figs 1–13 )

Material examined. Holotype 3, Australia: Victoria, Battery Creek, 146°7’42.3”E, 38°42’51.5”S, 144 m above sea level, 7 March 2012, planted Eucalyptus kitsoniana (K. Farnier & M.J. Steinbauer) , bred in greenhouse in LTUV (ANIC, dry mounted).

Paratypes. Australia: Australian Capital Territory: 1 3, 1 Ƥ, Canberra, 13 September 1959 (V.F. Eastop), 1960-144 (BMNH, slide mounted). – New South Wales: 6 3, 2 Ƥ, Orange, Dalton Street roundabout, 149°6’25.8”E, 33°16’31.1”S, 866 m above sea level, 15 March 2012, Eucalyptus viminalis (D. Burckhardt) (NHMB, dry mounted); – Tasmania: 3 3, 5 Ƥ, Hobart, 3 December 1986, Eucalyptus viminalis (D. Burckhardt) (MHNG, NHMB, dry and slide mounted); 4 3, 1 Ƥ, same but Marion Bay, West of Copping, 13 December 1986, various trees (MHNG, dry mounted); 2 Ƥ, same but 10 km South of Bronte, 10 December 1986, Eucalyptus spp. (MHNG, dry mounted); 1 Ƥ, Weegena, 9 June 1959, Eucalyptus (V.F. Eastop) VFE 7674, 1960-144 (BMNH, slide mounted). – Victoria: 8 3, 12 Ƥ, 26 larvae, same data as holotype (ANIC, ELEF, LTUV, MHNG, NHMB, dry and slide mounted and in ethanol); 13 3, 12 Ƥ, same data but (G.S. Taylor & M.J. Steinbauer) (WINC, dry mounted and in ethanol); 8 Ƥ, 22 larvae (5th instar 12, 4th instar 1, 3rd 4, 2nd 1, 1st 4), Hoddle Range, 146°7’55.6”E, 38°43’0.9”S, 254 m above sea level, 19 October 2011, planted E. kitsoniana (K. Farnier & M.J. Steinbauer) (LTUV, dry mounted); 5 3, 5 Ƥ, 125 larvae, nr Portland, Oakleys Rd, 141°31’6.4”E, 38°19’55.5”S, 7 May 2012, roadside reveg planting of E. kitsoniana and E. viminalis (M.J. Steinbauer) , (WINC, in ethanol); 1 3, 110 larvae, same but 7 May 2012; 1 larva, nr Portland, Post Office Rd, 147°20’33.1”E, 38°12’6.0”S, 8 May 2012, naturally seeded seedling of E. kitsoniana (M.J. Steinbauer) (WINC, in ethanol).

Description. Adult ( Figs 1–4 ). Colouration. When alive bright orange to light brown ( Fig. 14 ); eyes reddish. In dry mounted specimens head and pronotum light orange-brown, preocular tubercule and genal processes yellowish. Antennal segments 1 and 2 yellowish, 5–7 light brown, 8–10 dark brown to almost black. Thorax light reddish brown. Forewing with yellow to light brown veins; membrane semitransparent, indistinctly yellowish. Hindwing transparent, whitish. Legs brown, tibiae whitish, abdominal tergites brown, ventrites dirty whitish or yellowish, membranes reddish. Terminalia yellowish to light ochreous. Young specimens generally lighter in colour.

Structure. Head ( Fig. 5 ) strongly deflexed from longitudinal body axis; preocular sclerite forming distinct tubercule; genal processes about one third as long as vertex along mid-line, conical, subacute, contiguous in the middle in basal half; completely enveloping the median ocellus basally. Antenna short, 0.87–0.95 times head width, with a single subapical rhinarium on each of segments 4, 6, 8 and 9; segment 10 with one long curved apical seta, which is about as long as segment 10, and a very short truncate seta. Forewing ( Fig. 6 ) oblong-oval, 2.54–2.84 times as long as head width, 2.64–2.28 times as long as broad, more or less evenly rounded apically; pterostigma relatively broad, broadest near the middle; costal break present. Vein C+Sc very weakly, evenly curved, cell c+sc narrow; vein Rs almost straight, vein M long with short, widely diverging branches, vein Cu1b relatively long, evenly curved, in males reaching the margin at the point of bifurcation of vein M, in females often beyond point of bifurcation. Surface spinules present in all cells, forming irregular cellular pattern. Mesotibia with a subapical, longitudinal row of stout setae. Metacoxa with small, straight, weakly narrowing, apically blunt meracanthus. Metatibia longer than metafemur, 0.54–0.56 times as long as head width, with 5 almost equidistant short, strongly sclerotised apical spurs. Metabasitarsus with 2 small lateral sclerotised spurs. Male terminalia ( Figs. 7, 8 ) with basal segment of proctiger, in profile, without conspicuous stout pointed seta at the distal posterior angle; apical segment thin, tubular, 0.54–0.62 times length of basal segment; subgenital plate relatively small, triangular, in profile, with concave dorsal margin and longitudinal row of lateral setae. Paramere ( Figs. 9 , 14 ) lamellar, weakly curved forward with small finger-like process in basal third of hind margin, subacute apically; outer face sparsely covered in long setae, inner face with a group of thick setae apically and along fore margin, as well as a row of closely spaced peg-like setae starting from about apical third of the hind margin to the base; from behind, fingerlike process visible as narrow lobe with straight inner margin. Distal portion of aedeagus ( Figs. 10 , 15 ) with apical third or half imperceptibly inflated, apex narrowly rounded, sclerotised end tube of ductus ejaculatorius small, sshaped. Female terminalia ( Fig. 11 ) with proctiger 0.77–0.70 times as long as head width, 2.83–3.27 times as long as circumanal ring, 1.75–1.89 times as long as subgenital plate; dorsal margin of proctiger strongly concave, apical half of proctiger forming narrow process, truncate at apex, and bearing two lateral rows of small peg-like setae over four fifths of its length. Subgenital plate 0.44–0.57 times as long as proctiger, in profile broadly triangular at base, strongly narrowing in apical third. Valvulae dorsalis and ventralis moderately curved.

Measurements in mm (3 3, 3 Ƥ). Head width 0.49–0.58, Antenna length 0.46–0.51, forewing length 1.29–1.60, length of basal segment of male proctiger 0.16, length of distal segment of male proctiger 0.09–0.10, paramere length 0.11–0.14, length of distal portion of aeeagus 0.18–0.21, female proctiger length 0.43–0.45.

Fifth instar larva ( Fig. 16 ). Coloration. Larvae orange when alive; dirty whitish with yellowish or greyish sclerites when preserved in 70 % ethanol. Tip of antenna and tarsi dark brown, compound eyes red. Dorsum of head yellowish anteriorly. Abdomen with yellow mycetome visible in basal third.

Structure. Body ( Fig. 13 ) elongate, weakly sclerotised, 1.63–1.72 times as long as wide. Antenna indistinctly 9-segmented, a single rhinarium present on each of segments 3, 5, 7 and 8. Forewing pad 1.58–1.60 times as long as antenna. Tarsal arolium oval, lacking pedicel and unguitractor, shorter than claws. Caudal plate ( Fig. 12 ) angular, truncate apically, 0.71–0.91 times as long as wide. Circumanal ring terminal, small, consisting of a single row of pores. Additional pore fields present in the form of circular groups of 6–20 pores each; groups arranged in two irregular half circles on either side of caudal plate ( Figs. 12 (large arrows), 16), anterior semicircle in anterior third of caudal plate, posterior in posterior third. Lanceolate marginal setae ( Figs. 12 (small arrows), 16) forming three irregular groups in about basal third, in the middle and adjacent to circumanal ring.

Measurements in mm (4 larvae). Body length 1.04–1.29, antenna length 0.28–0.31.

Etymology. From Latin bipartitus = divided in two parts, referring to the paramere consisting of two lobes.

Biology. In southern Victoria, adults were found on native and planted Eucalyptus kitsoniana and E. viminalis between October (mid spring) and early May (mid autumn). In Tasmania, adults were collected in December on Eucalyptus viminalis and by general sweeping on various plants including Eucalyptus pauciflora and unidentified eucalypt species. A single female was collected in June on Eucalyptus sp. The series from the ACT was found in September and that from New South Wales in March on E. viminalis .

Adults appear feeding on juvenile foliage and are usually most abundant in opening leaf buds and on very recently expanded leaves. Adults spend most of the time feeding and usually disperse only when disturbed. Mating occurs at feeding sites ( Fig. 17 ). Eggs are most often deposited inside closed apical buds. Females may be induced to lay by insertion of the ovipositor into tight crevices, e.g. between pairs of leaves.

In the field, on planted hosts in Victoria, larvae were found between October and May inside apical buds and never on expanding leaves. Densities are typically low (5.9 ± 0.8 larvae per bud, n = 63 observations from seven trees), only rarely reaching high numbers (e.g. 38 larvae in a bud). Larvae produce wax strands ( Figs. 18, 19 ) similar to those of C. eucalypti . Honeydew is encapsulated in the flocculent waxy material ( Figs. 18, 19 ). High numbers of larvae in closed apical leaf pairs induce leaf rolls ( Fig. 20 ). Condensation can be observed inside leaf rolls when opened indicating that they provide larvae with high humidity microhabitats in which to develop. Severely distorted young leaves often do not expand normally ( Fig. 20 ). Leaf rolling was not observed in the field when larval densities were low, e.g. <5 larvae per leaf.

In the laboratory larvae reach maturity within three weeks when reared under a 20:10°C for 12:12 hours temperature regime. Mummified larvae with serrated exit holes have been observed in the wild suggesting that the species is attacked by parasitoid wasps. A regular psyllid infestation of small E. kitsoniana seedlings was observed in a nursery (F. Smolders, pers comm.). This population is currently in greenhouse culture at LTUV.

Figures

FIGURES 1 – 4. Habitus of adult Ctenarytaina bipartita sp. n. 1. Male, in profile. 2. Male, in dorsal view. 3. Female, in profile. 4. Female, in dorsal view.

FIGURES 5 – 13. Ctenarytaina bipartita sp. n.: 5 – 11 — Adult. 12, 13 — Fifth instar larva. 5. Head, dorsal view. 6. Forewing. 7, 8. Male terminalia, in profile. 9. Paramere, inner surface. 10. Aedeagus, distal portion. 11. Female terminalia, in profile. 12. Caudal plate, left half, dorsal view. 13. Habitus.

FIGURES 14 – 16. Ctenarytaina bipartita sp. n.: 14, 15 — Adult. 16 — Fifth instar larva. 14. Paramere, inner surface. 15. Aedeagus, distal portion. 16. Caudal plate, left half, dorsal view.

FIGURES 17 – 20. Ctenarytaina bipartita sp. n. 17. Mating adults. 18. Waxy flocculence and honeydew on leaf of Eucalyptus kitsoniana. 19. Fifth instar larvae with wax strands and honeydew excretions. 20. Rolls of young leaves of Eucalyptus kitsoniana.