Trioza alifumosa Klyver, 1932

Martoni, Francesco & Brown, Samuel D. J., 2018, An annotated checklist of the Cook Islands psyllids with keys to the species and two new records (Hemiptera, Psylloidea), ZooKeys 811, pp. 91-108 : 91

Trioza alifumosa Klyver, 1932 Figures 11-20, 26

Material examined.

11 females, 8 males. A single population of this species was collected on Rarotonga, on the summit of Raemaru at an elevation of 380 m. On 16 March 2017 all 19 individuals were collected from a single plant of Metrosideros collina (J.R.Forst. and G.Forst.) A.Gray.

Measurements.

Measurements are in mm (n = 2 ♂, 3 ♀ unless reported differently in brackets). Length of body (vertex to terminalia) ♂ 1.30-1.45, ♀ 1.60-1.78; length of body (vertex to apex of folded wings) ♂ 2.57-2.81, ♀ 2.86-3.10; width of head (HW) ♂ 0.50-0.53, ♀ 0.52-0.57 (n = 2); length of genal processes (GCL) ♂ 0.09-0.14 ♀ 0.10-0.13 (n = 2); length of vertex (VL) ♂ 0.21, ♀ 0.20-0.25 (n = 2); width of vertex (VW) ♂ 0.31-0.32, ♀ 0.32-0.33 (n = 2); length of antenna (AL) ♂ 0.78-0.79, ♀ 0.81-0.85 (n = 2); length of fore wing ♂ 2.27-2.28, ♀ 2.38-2.57 (n = 2); width of fore wing ♂ 0.83-0.86, ♀ 0.85-0.96 (n = 2); length of vein Rs ♂ 0.91-0.99, ♀ 1.00-1.08 (n = 2); length of vein M (M) ♂ 1.11-1.12, ♀ 1.15-1.24 (n = 2); length of vein M1+2 (M1) ♂ 0.44-0.48, ♀ 0.54-0.56 (n = 2); marginal width of cell m1 ♂ 0.28-0.32, ♀ 0.38 (n = 2); marginal width of cell cu1 ♂ 0.40-0.42, ♀ 0.42-0.44 (n = 2); length of vein Cu1b ♂ 0.23-0.25, ♀ 0.21-0.25 (n = 2); length (height) of proctiger (PL) ♂ 0.15-0.20; length of paramere ♂ 0.11-0.13; length of proximal aedeagal segment ♂ 0.17 (n = 1); length of distal aedeagal segment ♂ 0.16 (n = 1); length of proctiger (PL) ♀ 0.30-0.51; length of circum-anal ring (CL) ♀ 0.10-0.13; length of subgenital plate (SL) ♀ 0.29-0.34.

Description.

This psyllid can be identified by the following combination of characters: habitus as in Figures 11-14, with a dark brown colour, fore wings with an infuscate spot in the apical costal cell as in Figures 13, 17, female proctiger short and bearing setae on the subgenital plate (Figure 19); male parameres elongate, slightly back-turned apically and bearing setae (Figure 20). Both this species and T. alipellucida Klyver, 1932, were described from material collected on Metrosideros collina . The evenly dark colouration of the dorsal surface and head, the presence of an infuscate spot in the apical costal cell (c+sc), the rounded but elongated shape of the aedeagus, the elongated shape of the male proctiger and the slightly back-turned parameres lead us to place it in T. alifumosa . Trioza alipellucida differs from T. alifumosa by most specimens having a wide lighter brown stripe on the pronotum, not having an infuscate spot at the base of the forewing, and for a shorter male proctiger associated with parameres that are not as back-turned. The morphological distinction between T. alifumosa and T. zimmermani appears more immediate, with the latter presenting light stripes dorsally on a dark brown abdomen and having hyaline wings without any dark spot in the cell c+sc ( Tuthill 1942).