Psylla cirrita, Burckhardt, 2024

Burckhardt, Daniel, 2024, The Psyllinae (Hemiptera, Psyllidae) from Gunung Kinabalu (Malaysia, Sabah), Alpine Entomology 8, pp. 1-17 : 1

Psylla cirrita sp. nov.

Figs 40 , 41 , 44-47

Type locality.

Malaysia, Sabah, Ranau, Gunung Kinabalu, Kinabalu Park, summit trail, Panar Laban; 6.0594°N, 116.5665°E, 3300 m.

Material examined.

Holotype. Malaysia • ♂; Sabah, Ranau, Gunung Kinabalu, Kinabalu Park , summit trail, Panar Laban ; 6.0594°N, 116.5665°E; 3300 m; 4.v.1987; D. Burckhardt and I. Löbl leg.; #F8764; on Rhododendron sp. ( Ericaceae ) in moss forest with Ericaceae and Myrtaceae ; MHNG, dry.

Diagnosis.

Adult. Vertex 0.4 times as long as wide; genal processes 1.0 times as long as vertex along midline, massive, evenly tapering to pointed apex, contiguous medially. Antenna 2.6 times as long as head width; relative length of flagellar segments as 1.0: 1.0: 0.9: 1.1: 1.2: 1.2: 0.2: 0.3. Metatibia bearing small genual spine. Forewing oblong-oval, widest in the middle, 3.2 times as long as head width, 2.4 times as long as broad; pterostigma regularly narrowing to apex, ending level with the middle of Rs; vein Rs weakly sinuate; vein M long, with relatively short, weakly diverging branches; vein Cu1a strongly curved in basal half. Surface spinules present in all cells, leaving spinule free stripes along the veins; forming irregular transverse rows. Male proctiger tubular, weakly sinuate, 0.4 times as long as head width. Subgenital plate strongly sclerotised, in lateral view subglobular, with almost straight dorsal margin. Paramere shorter than proctiger, in lateral view, lamellar, weakly curved, with strongly sclerotised apical hook, curved inwards and forwards. Distal segment of aedeagus bearing hook-shaped apical inflation.

Description.

Adult. Colouration. Dark reddish brown. Genal processes ochreous. Antenna dark brown, segments 1-3 brown, apices of segments 3-8 and entire segments 9 and 10 almost black. Mesoscutum with four indistinct longitudinal brown stripes; mesoscutellum reddish brown laterally; metanotum and metapostnotum ochreous. Legs irregularly ochreous; apical tarsal segments greyish brown. Forewing colourless at base, becoming yellow towards apex; veins brown. Abdomen including terminalia yellowish; tip of paramere black.

Structure. Conforming to the generic description of Li (2011). Body length 4.7 mm (1 ♂). Head deflexed 45° from longitudinal axis of body (Fig. 40 ); about as wide as mesoscutum. Vertex (Fig. 41 ) rhomboidal, 0.4 times as long a wide, weakly concave at base, bearing short sparse setae and fine granular microsculpture; preocular sclerite narrow; genal processes 1.0 times as long as vertex along mid-line, massive, evenly tapering to pointed apex (Fig. 41 ), contiguous medially, evenly beset with sparse long setae; eyes hemispherical. Rostrum short, in lateral view mostly hidden by mesosternum and only apical segment visible. Antenna 2.6 times as long as head width; relative length of flagellar segments as 1.0: 1.0: 0.9: 1.1: 1.2: 1.2: 0.2: 0.3; antennal segments 7 and 8 longest; relative length of segment 10 and terminal antennal setae as 1.0: 0.6: 0.6. Metatibia 0.7 times as long as head width, bearing small genual spine, weakly widening to apex, with 1+4+1 apical spurs. Forewing (Fig. 40 ) oblong oval, widest in the middle, 3.2 times as long as head width, 2.4 times as long as broad, irregularly rounded apically; pterostigma, at base narrower than adjacent part of cell r1, regularly narrowing to apex, ending level with the middle Rs; vein C+Sc weakly curved, cell c+sc long, widest in the middle; vein Rs weakly sinuate; vein M long, with relatively short, weakly diverging branches; vein Cu1a strongly curved in basal half. Surface spinules present in all cells, leaving spinule free stripes along the veins; forming irregular transverse rows.

Male terminalia as in Figs 44-47 . Proctiger tubular, weakly sinuate, 0.4 times as long as head width; densely beset with long setae in apical three quarters. Subgenital plate strongly sclerotised, in lateral view subglobular, with almost straight dorsal margin; sparsely beset with long setae along a broad transverse band stretching from dorsal margin to postero-ventral margin. Paramere shorter than proctiger, in lateral view, lamellar, weakly curved, with strongly sclerotised apical hook which is curved inward and forward; parameres in caudal view, forming O with dorsally widening margins; outer face sparsely beset with long setae in apical two thirds; inner face with a subapical group of long bristles, and long setae along fore and hind margin. Aedeagus long and slender; distal segment bearing rounded apical inflation; sclerotised end tube of ductus ejaculatorius short, sinuate. - Female unknown.

Measurements in mm (1 ♂). Head width 1.12; antenna length 2.88; forewing length 3.56; male proctiger length 0.40; paramere length 0.38; length of distal portion of aedeagus 0.28.

Fifth instar immature unknown.

Etymology.

From Latin cirritus = having filaments, bearded, referring to the conspicuous setae on the genal processes.

Distribution.

Malaysia: Sabah, Gunung Kinabalu, at an altitude of 3300 m.

Host plant, biology and habitat.

Unknown; the holotype was collected on Rhododendron sp. ( Ericaceae ) in moss forest with Ericaceae and Myrtaceae .

Comments.

Psylla cirrita shares with Psylla turpinae Li & Yang from the Guangxi Zhuang Autonomous Region (PR China) the reddish body colour, the massive genal processes, the 1+4+1 apical metatibial spurs, the postero-basally expanded male proctiger and the apically hardly expanded distal segment of the aedeagus. It differs from P. turpinae in the pointed (versus blunt) genal processes, the antennal segment 3 that is shorter (versus longer) than segments 7 and 8, and the curved (versus sinuate) parameres. If the similarity between the two species reflects a phylogenetic relationship, this needs to be tested with more material and, in particular, with immatures. A related, undescribed species was found on Gunung Kinabalu (see comments under Psylla sp.). According to Li (2011), P. turpinae develops on Dalrympelea pomifera Roxb. ( Staphyleaceae ), an unusual psyllid host taxon. It is interesting to note, that of the eight species recognised in the Southeast Asian genus Dalrympelea six occur in Borneo ( POWO 2023).

Psylla cirrita and P. turpinae are not congeneric with P. alni (Linnaeus, 1758), the type species of Psylla Geoffroy, 1762. Based on molecular and morphological evidence, Psylla was redefined to include Holarctic species developing on Betulaceae ( Burckhardt et al. 2021). The two Asian species possibly constitute a new genus but more material including immatures is necessary to examine their phylogenetic position. Meanwhile, I use the broad concept of Psylla by Li (2011).

Figures

Figures 40 - 43. Psylla spp. 40, 42. Habitus, in lateral view; 41, 43. Head, in dorsal view. 40, 41. P. cirrita; 42, 43. Psylla sp.

Figures 44 - 47. Psylla cirrita. 44. male terminalia, in lateral view; 45. outer face of paramere; 46. inner face of paramere; 47. apex of distal aedeagal segment.