Neighbour-joining (NJ) analysis (combined COI and cytB data) with 1000 bootstrap replicates in PAUP*. Eight of the nine Swezeyana species are included and 16 other taxa from Triozidae, mostly representing other Hawaiian genera for comparison of divergence; and one species from Carsidaridae as an outgroup (Mesohomotoma hibisci) (Table 1). Outlines of parameres and female terminalia illustrate the two recognized species groups (elongagena group in black, reticulata group in grey, S. magnaccai unplaced), and fore wing images (Fig. 1) show the distribution of patterned/pigmented wings. Regional localities of sample are given, and “imm.” indicates an immature sampled for S. reticulata. NJ bootstrap support values ≥ 60% are indicated for all nodes, and comparative node support from ML and Bayesian analyses are shown for the three same island sister taxa pairs (NJ/ML[bold]/Bayesian[italic]) (see Discussion). Maximum genetic divergence (uncorrected p-distances) is shown for Swezeyana and four other endemic Hawaiian genera; also shown are maximum intraspecific distances (indicated with an asterix) for two widespread non-Hawaiian species with multiple individuals sampled across terrestrial (T. urticae) or oceanic (M. hibisci) landscapes (see Discussion).

Swezeyana elongagena. A head B head (lateral view) C male D head and antenna, inset detail of terminal antennal segments (terminal setae outlined) E female terminalia F detail of apex of female terminalia indicating beak and position of medial clefts in proctiger and subgenital plate (outlined) G male terminalia H paramere and distal aedeagus segment I paramere, inset detail of apex J eggs (distinctly hexagonal sculpturing and pedicel outlined and indicated) K hind leg L base of hind tibia with reduced genual spine indicated M mesotarsi and metatarsi (outlined), concave and ridged underside of basal metatarsus (outlined) N small but distinct meracanthus (indicated) O fore wing with interior edge of ventral margin outlined, inset illustrating broad shape of marginal radular spine cluster P extent of fore wing pseudopterostigma (shaded).

Swezeyana atra sp. n. A head B head and antenna (lateral view) C antenna D proboscis E dorsum of thorax F male terminalia, inset distal aedeagus segment G paramere and distal aedeagus segment H parameres (dorsal view), inset illustrating paramere apex I paramere (posterior view) J female abdomen K female terminalia L female proctiger (dorsal view) M detail of anal ring N female subgenital plate (ventral view) O detail of posterior apex of female subgenital plate with membrane (outlined) P female terminalia endoskeleton (dorsal view, outlined) Q hind leg, inset reduced meracanthus (indicated) and metatarsi (outlined) R base of hind tibia with highly reduced genual spine (indicated) S extent of fore wing pseudopterostigma (shaded) T fore wing (above) with interior edge of ventral margin outlined, hind wing (below).

Fore wings of nine Swezeyana species: A S. elongagena (male) B S. oahuensis (male) C S. atra (male) D S. magna (male) E S. hawaiiensis (female) F S. magnaccai (male) G S. reticulata (male above, female below) H S. tentaculata (male above, female below) I S. rubra (male above, female below). Scale bars: 1 mm.