Cheiloxena blackburni Reid, 1992

Reid, C. A. M. & Beatson, M., 2018, Revision of the Australian leaf beetle genus Cheiloxena Baly, 1860 (Coleoptera: Chrysomelidae: Spilopyrinae), Zootaxa 4497 (4), pp. 501-534 : 511-512

Cheiloxena blackburni Reid, 1992

( Figs 4 , 14 , 23 , 32 , 44 , 53 , 63 , 70, 77 )

Cheiloxena blackburni Reid 1992: 102 (type locality: Blackheath, NSW)

Material examined. Types: Paratypes (5): Ƌ/ Blue Mts N. S. Wales/ E. W. Ferguson collection/ Cheiloxena sp. W. K. Hughes det./ Cheiloxena blackburni Reid / AN25 001071/ (ANIC); ♀/ Blue Mts N. S. Wales/E. W. Ferguson collection/ Cheiloxena sp. W. K. Hughes det./ Cheiloxena blackburni Reid / AN25 001072/ (ANIC); ♀/ Blue Mts N. S. Wales/E. W. Ferguson collection/ Cheiloxena sp. W. K. Hughes det./ Cheiloxena blackburni Reid / AN25 001073/ (ANIC); ♀/ Blue Mts N. S. Wales/ Cheiloxena sp. not insignis not westwoodi E. B. Britton det/ Cheiloxena blackburni Reid / AN25 001074/ (ANIC); ♀*/ Blue Mts N. S. Wales/ John Carter/ Cheiloxena ? frenchae Blackb. / Cheiloxena blackburni Reid / AN25 001075/ (ANIC).

Non-types: ♀/ Kosc. 12.i.1935 / student’s collection/ (AMS); 2♂*/ Blue Mts/ Cheiloxena westwoodi Blue Mts NSW/ ex H. W. Brown coll./ (AMS).

Diagnosis. Cheiloxena blackburni is distinguished by: upper and lower surfaces scaled; anterior margin of clypeus truncate; pronotum with posteriorly divergent paired ridges; hypomeral lobe rugose, without scales; apical half of elytra with small inconspicuous tubercles.

Description. Length: male 10.5–11 mm, female 12–15 mm; body moderately convex in profile, length about 3x height; colour dark brown to almost black, except labrum and legs dark reddish-brown; entirely sparsely clothed with short adpressed scale-like setae (length 3– 4x width and about equal to puncture diameters), setae thinner and sparser on appendages and apical ventrites; pronotum and elytra dull, punctate and densely microsculptured, except shining apices of tubercles and ridges.

Head ( Figs 4 , 14 , 23 ): as wide as pronotum (male) or distinctly narrower than pronotum (female); densely and slightly confluently punctured, intervals shining not or feebly microsculptured; narrow impunctate smooth area around antennal cavities; elevated between eyes, but flat between antennae, without grooves on vertex including midline; eyes small, slightly laterally prominent, separated by about 4 eye widths (male) or about 7 eye widths (female); gena at shortest point about 0.4x eye length (male) or about 0.6x eye length (female); genal lobe 0.75x shortest length gena; antennae about 4x socket diameters apart; antennae about 0.75x body length (male), or about 0.6x body length (female); antennomeres 1 and 3–11 elongate, 2 transverse <0.5x length 1, <0.3x length 3, relative lengths of antennomeres with 3 longest and 7 next, in both sexes and most middle segments of similar length: 2 shortest, <1, <4=6=8=9=10, <5, <11, <7, <3; clypeus with 2–3 pairs of long subapical setae; clypeal anterior margin truncate; male apical maxillary palpomere elongate-ovate with truncate apex.

Thorax ( Figs 4 , 14 , 23 , 32 ): pronotal sides almost vertical, no clear distinction between dorsal and ventral (hypomeral) areas of pronotum; pronotal puncturation as head, except interspaces dull; pronotal width 1.03x length (length almost equal width), greatest width at anterior third and sides weakly sinuate; anterior angles prominent, 60°; anterior margin produced but concave at middle; lateral margins without tubercles or lobes; basal margin weakly convex; pronotal disc with pair of narrow elevated oblique ridges from sides of middle to anterior margin, ridges splayed laterally towards posterior, abruptly terminating posteriorly in lateral view, disc with low swelling near base of midline, and laterally uneven; hypomeron and prosternum closely punctured and scaled, as pronotum, except hypomeral lobe rugose and glabrous; scutellum punctured and setose, as pronotum; elytral scale-like setae in irregular patches; elytron tuberculate, the irregularly sized shiny tipped tubercles arranged in 4 longitudinal rows, as follows: first (innermost) with 7–10 small tubercles, largest posterior to humerus; second with 5–8 small tubercles, largest level with apex of hind femur; third starting on inner surface of humerus, with 5–10 small tubercles; fourth starting on outer surface of humerus, with 5–8 small tubercles; elytral disc shallowly transversely depressed in basal half, posterior to humerus; elytral punctures large, about 1.5x pronotal puncture diameters, and sparse, separated by 1–1.5x diameters, interspaces dull, microsculptured; elytral punctures on disc with two small shining tubercles laterally on rim; elytral apex narrowly truncate; epipleuron finely and shallowly punctured with scale-like pubescence; mesoventrite punctured as prosternum; metepisternum and metaventrite shining, not or shallowly microsculptured, sparsely punctured and scaled, except midline impunctate for posterior 2/3; metatibiae with shallow irregular lateral longitudinal grooves, thin and elongated; bases of tarsomeres 1–3 depressed; protarsomeres 1–3 slightly broader at base in male than female.

Abdomen ( Figs 44 , 53 , 63 , 70): ventrite I smooth and shining at middle, closely and strongly punctured and microreticulate at sides; II–V densely punctured, shining at middle but shallowly microreticulate, dull at sides; ventrite pubescence recumbent, scale-like throughout, erect setae only present on apical margin of ventrite V; apex of ventrite V convex in both sexes; apex of penis contracted to blunt mucronate tip in dorsal view, apex thin and elongate in lateral view; tegminal keel shallowly sinuate in lateral view; female sternite VIII apodeme short and broad, apical sclerotised area triangular, longer than wide, apex bilobed with rounded lobes; apex of outer margin of gonocoxite with several long setae; stylus only slightly elongate; median ventral sclerite elongate, only lateral margins distinctly sclerotised; spermatheca falcate, acutely tipped, with simple uncoiled duct.

Notes. Cheiloxena blackburni is only known from the Blue Mountains, NSW ( Fig. 77 , including aditional localities from Reid 1992), Kosciuszko National Park region (a specimen labelled 'Kosc.'), at least 250 km further south, and a single specimen from Balook, Victoria, in MVM ( Reid 1992). We think the Balook specimen was mislabelled by Charles Oke, former curator of the MVM entomology collection. Balook is a lowland site with quite different vegetation from Blackheath in the Blue Mountains, which is the only other definitive locality for this species. There is a similar label problem for a specimen of C. insignis (see below). The 'Kosc' female is lacking its abdomen and is without detailed locality information.

All of the known specimens of Cheiloxena blackburni are old, mostly from the collections of E. W. Ferguson (1884–1927), H. W. Brown (1883–1958) and H. J. Carter (1858–1940) ( Daniels 2004). Only one is dated, anonymously collected in January 1935 (the 'Kosc' specimen). In the unlikely event Brown collected his specimens in the last year of his life, the most recent collection date for this large beetle species is 1958, at least 60 years ago.

Figures

FIGURE 77. Eastern Australia showing distribution of Cheiloxena species.

FIGURES 3–6. Habitus of Cheiloxena species: 3, C. aitori Reid & Beatson, male; 4, C. blackburni Reid; 5, C. conani Reid & Beatson; 6, C. frenchae Blackburn. Not to scale.

FIGURES 13–21. Lateral of Cheiloxena species: 13, C. aitori Reid & Beatson, male (holotype); 14, C. blackburni Reid; 15, C. conani Reid & Beatson; 16, C. frenchae Blackburn, (holotype); 17, C. insignis Blackburn; 18, C. monga Reid & Beatson (holotype); 19, C. tuberosa Reid; 20, C. westwoodii Baly (northern form, Dorrigo); 21, C. westwoodii Baly (southern form, Victoria). Not to scale.

FIGURES 22–30. Anterior view, Cheiloxena species: 22, C. aitori Reid & Beatson, male (holotype); 23, C. blackburni Reid; 24, C. conani Reid & Beatson; 25, C. frenchae Blackburn; 26, C. insignis Baly; 27, C. monga Reid & Beatson; 28, C. tuberosa Reid; 29, C. westwoodii Baly (northern form, Dorrigo); 30, C. westwoodii Baly (southern form, Victoria).

FIGURES 31–34. Dorsal of pronotum, Cheiloxena species: 31, C. aitori Reid & Beatson, male (holotype); 32, C. blackburni Reid; 33, C. frenchae Blackburn; 34, C. monga Reid & Beatson.

FIGURES 43–51. Cheiloxena species, male genitalia lateral and dorsal: 43, C. aitori Reid & Beatson; 44, C. blackburni Reid; 45, C. conani Reid & Beatson; 46, C. frenchae Blackburn; 47, C. insignis Blackburn; 48, C. monga Reid & Beatson; 49, C. tuberosa Reid; 50, C. westwoodii Baly (northern form, Dorrigo); 51, C. westwoodii (southern form, Victoria). All images to scale, scale bar = 2mm.

FIGURES 52–61. Cheiloxena species, apex of penis: 52, C. aitori Reid & Beatson; 53, C. blackburni Reid; 54, C. conani Reid & Beatson; 55, C. frenchae Blackburn; 56, C. insignis Blackburn (Launching Place, Victoria); 57, C. insignis Blackburn (Lake Mountain, Victoria); 58, C. monga Reid & Beatson; 59, C. tuberosa Reid; 60, C. westwoodii Baly (northern form, Dorrigo); 61, C. westwoodii (southern form, Victoria). All images to same scale.

FIGURES 62–68. Cheiloxena species, female genitalia: 62, C. aitori Reid & Beatson; 63, C. blackburni Reid; 64, C. conani Reid & Beatson; 65, C. frenchae Blackburn; 66, C. insignis Blackburn; 67, C. tuberosa Reid; 68, C. westwoodii Baly (northern form, Dorrigo).