Dixamflata, Stroiński & Malenovský & Świerczewski, 2016

Stroiński, Adam, Malenovský, Igor & Świerczewski, Dariusz, 2016, Two new genera offlatid planthoppers from Socotra island (Hemiptera: Fulgoromorpha: Flatidae), Acta Entomologica Musei Nationalis Pragae 56 (2), pp. 461-489 : 463-466

Dixamflata gen. nov.

( Figs 1–52 )

Type species. Dixamflata petri sp. nov., here designated.

Diagnosis. Frons with large, apically broadly rounded crown in upper part, median carina, and intermediate carinae present as ridges forming horseshoe shaped bulge anteriorly. Tegmina short (“sub-brachypterous”), coriaceous with apical part produced and several groups of sensory sensilla (tubercles) on the surface; clavus with A 1 basally strongly elevated. Male and female anal tube, in lateral view, elongate and curved, tapering apicad; in dorsal view basal part wider than apical part, anus situated near midlength in males, in basal half in females. Genital style with short ventroapical tooth-like process on inner side. Dorsal part of periandrium with a single one-armed process; ventral part with median keel. Female anal tube reaching posterior margin of gonoplac. Gonoplac unilobate, sub-rectangular, posterior margin with two rows of teeth. Bursa copulatrix with single pouch.

Description. Head. Head with compound eyes, in dorsal view, narrower than thorax ( Figs 3 , 10, 11 ). Vertex transverse, shorter than pronotum, trapezoidal, with posterior margin carinate, lateral margins obsolete, anterior margin visible as transverse ridge at mid-length of head in dorsal view; disc without carina ( Figs 4 , 9–13 ). Frons with well-developed crown in dorsal view – semicircular, longer than vertex in midline, dorsal portion depressed medially and with short median ridge in anterior part that is visible in oblique anterior view; lateral margins of frons carinate, regularly arcuate in both lateral and ventral views, without incisions ( Figs 5, 7 , 8, 13–16 ); disc of frons, in ventral view, with intermediate carinae developed as obsolete ridges and forming horseshoe-shaped bulge anteriorly, median carina present; frontoclypeal suture arcuate, ventral margin of frons slightly concave ( Figs 5, 6 , 15, 16 ). Clypeus without carinae ( Figs 15, 16 ). Rostrum with apical segment shorter than subapical one, narrowing to apex, apex reaching hind coxae ( Fig. 17 ). Compound eyes rounded, with small callus at posterior and ventral margins. Lateral ocelli absent ( Figs 1, 2, 7–9, 13 , 14 ). Antenna located ventrally in respect to eye; scapus distinctly shorter than diameter of eye, cylindrical, scarcely covered with short setae; pedicel shorter than diameter of eye but distinctly longer than scapus, barrel-shaped, apical part concave, functional area at the top and on dorsal surface with trichoid sensilla type 1, antennal plate organs present on apical concavity and delimiting laterally dorsal functional surface ( Figs 7 , 18, 19 ).

Thorax. Pronotum disc with median ridge and lateral gibbosities, not reaching posterior and anterior margins; area between median ridge and gibbosities depressed; postocular eminences small and conical; anterior margin of pronotum medially produced till half of eye length, with median incision; posterior margin widely and shallowly concave ( Figs 3, 4 , 10–13 ). Mesonotum triangular; short keel-shaped median carina present only in median portion; lateral carinae in form of ridges, subparallel, reaching both anterior and posterior margins; area between median carina and lateral ridges depressed; scutellum posteriorly sharply angled ( Figs 3, 4 , 10–13 ).

Tegmen coriaceous, irregularly convex with distinct venation; costal margin strongly arcuate, convex, weakly concave in apical one fifth, costal angle widely, bluntly rounded; sutural angle bearing a large, rounded hump produced dorsally, postclaval sutural margin short, ending a bit posterior to second ScRA terminal; apical part of tegmen produced posteriorly and narrowly rounded, relatively longer and slender in males, shorter and more robust in females ( Figs 22–28 ). Costal area narrower than postcostal cell, with ca. 14–20 transverse veinlets, terminating anterior to level of clavus apex; postcostal cell with several (ca. 4) transverse veinlets. Basal cell long and narrow; ScRA+RP leaving basal cell with common stem, ScRA elevated, RP between basal cell and bulla obsolete; ScRA ending with two terminals, not extending to the level of clavus; RP single, terminating at posterior margin posterior to clavus apex; MP forking posterior to the sensory area, ending with 4–5 obsolete terminals; CuA single, terminating at postclaval margin. Clavus with A 1 basally strongly elevated, area between Pcu and A 1 concave; Pcu and A 1 fused anterior to clavus apex; several transverse veinlets between A 1 and A 2. Tubercles present on the whole tegmen with concentration in the following parts: basal part of clavus – between A 1 and A 2 and between Pcu and A 1, basal part of costal membrane, and on bulla between ScRA and RP ( Figs 22 , 24, 28 ). Sensory sensilla long and thin with blunt apex, present on whole tegmen except apical part, where shorter and thicker sensilla with sharp apex are present (mostly broken-off on dry specimens) ( Figs 29, 30 ). Hindwing well developed.

Femora shorter than tibiae; hind tibiae weakly curved, triangular in cross section, with two lateral spines placed in distal half, apically with row of seven well-developed spines (5 short + 2 long); basitarsomere slightly longer than cumulative length of tarsomeres 2 and 3, with row of eight apical spines and setae; second tarsomere with two lateral spines and median pad with thick setae ( Figs 20, 21 ).

Male terminalia. Anal tube, in lateral view, elongate and curved, tapering apicad; anus placed at midlength ( Figs 31, 32 , 35 ); in dorsal view elongate, tapering apicad, apically concave in median portion, widest slightly anterior to anus ( Figs 33, 34 ). Pygofer, in lateral view higher than long, dorsal part narrower than ventral part, anterior and posterior margins arcuate ( Figs 31, 32 , 35 ). Genital styles longer than wide and bearing long, dorsocaudal, arcuate capitulum; dorsal margin straight without concavity and extra fold, posterior and ventral margins weakly convex, posteroventral angle with short, blunt process on inner side ( Figs 31, 32 , 35 ).

Phallic complex. Periandrium elongate, upcurved, slightly longer than aedeagus, apical part wider than basal part; lateral split not reaching midlength ( Figs 36, 37 ). Dorsal part of periandrium almost as long as ventral part, apically with distinct appendage divided into short base and one-armed process. Ventral part of periandrium, in cross-section, V-shaped, with additional distinct, median keel in apical two thirds; in ventral view, unilobate, tapering apicad, with lateral margins serrate. Basal part of periandrium with long and narrow lateral lobe.Aedeagus long, with apical, bulb-like, sclerotized appendages; deep median split reaching basal part; shaft of aedeagus curved ( Figs 38, 39 ).

Female terminalia. Pregenital sternite with X-shaped, strong sclerotization in median portion; posterior margin with long and narrow, arcuate fold ( Figs 42, 43 , 46 ). Anal tube, in lateral view ( Figs 41–43 ), curved ventrad, tapering apicad, with bluntly rounded apex; anal tube covering gonoplac and reaching its posterior margin; anus placed in basal half; in dorsal view, elongately oval; posterior margin in median portion with shallow incision ( Figs 40, 44, 45 ). Gonoplac unilobate, sub-rectangular; posterior margin with two rows of teeth; dorsal part of posterior margin to the level of teeth limit well sclerotised, ventral part membranous without setae ( Figs 41–43, 45 , 47 ). Gonapophysis VIII ( Fig. 48 ) triangular, laterally flattened; dorsal margin sinuate, ventral margin arcuate and slightly up-folded; both margins with subapical teeth; endogonocoxal process about as long as gonapophysis, distinctly tapering apicad, membranous with distinct spiniferous microsculpture. Gonospiculum as in Figs 49–50 . Bursa copulatrix with single pouch, kidney-shaped, cells with weakly sclerotized central areas with microsculpture on the surface ( Fig. 51 ). Spermatheca well developed, ductus receptaculi slightly longer than diverticulum ductus ( Fig. 52 ).

Remarks. Dixamflata differs from the two flatid genera so far recorded from Socotra, i.e. Mosiona and Kirkamflata , in a much smaller size, short coriaceous tegmina and coloration (both Mosiona and Kirkamflata are large, macropterous, with membranous tegmina, and uniformly dark brown or yellowish-green, respectively: MELICHAR 1923, ŚWIERCZEWSKI et al. 2014). Dixamflata is similar in habitus to Kesaflata gen. nov. described here below – see the Remarks section under the latter for diagnostic characters as well as the Discussion for a comparison with other similar genera in a wider region.

Etymology. The generic name is a combination derived from “ Dixam ”, a local name of the highland plateau on southern slopes of the Hagher mountains where the type species was collected, and “ Flata ” which is used here for a representative of the Flatidae family. Gender feminine.

Distribution. Yemen: Socotra island.

Figures

Figs 1–7. Dixamflata petri gen. & sp. nov. 1 – habitus, lateral view; 2 – habitus of another specimen, lateral view; 3 – habitus, dorsal view; 4 – anterior part of body, dorsal view; 5–6 – same, frontal view; 7 – same, lateral view.

Figs 8–13. Dixamflata petri gen. & sp. nov., SEM micrographs. 8 – habitus, lateral view; 9 – same, dorso-lateral view; 10 – same, dorsal view; 11 – same, dorso-caudal view; 12 – anterior part of body, dorsal view; 13 – same, dorso-lateral view.

Figs 14–19. Dixamflata petri gen. & sp. nov., SEM micrographs. 14 – anterior part of body, lateral view; 15–16 – frons, frontal view; 17 – rostrum, ventral view; 18 – antenna, dorso-lateral view; 19 – antennal plate organs.

Figs 20–22. Dixamflata petri gen. & sp. nov., SEM micrographs. 20 – hind leg, general view; 21 – hind leg, apical part; 22 – tegmen, lateral view.

Figs 23–28.Dixamflata petri gen.& sp. nov., tegmen, SEM micrographs.23 – apical part; 24 – basal part; 25 – caudal part, lateral view; 26 – ventral part; 27 – caudal part, dorsal view; 28 – clavus, dorsal view.

Figs 29–34. Dixamflata petri gen. & sp. nov., SEM micrographs. 29–30 – tegmen, sensory area; 31–32 – male abdomen, lateral view; 33 – same, dorsal view; 34 – anal tube, dorsal view.

Figs 35–39. Dixamflata petri gen. & sp. nov., male. 35 – male terminalia, left lateral view; 36 – periandrium, lateral view; 37 – same, ventral view; 38 – aedeagus, ventral view; 39 – aedeagus, lateral view.

Figs 40–45. Dixamflata petri gen. & sp. nov., female, SEM micrographs. 40 – abdomen, dorsal view; 41 – abdomen, lateral view; 42 – terminalia, ventral view; 43 – terminalia, lateral view; 44 – anal tube, dorso-lateral view; 45 – terminalia, caudal view.

Figs 46–52. Dixamflata petri gen. & sp. nov., female. 46 – pregenital sternite, flattened, ventral view; 47 – right gonoplac, external view; 48 – gonapophysis VIII, lateral view; 49 – gonapophyses IX and gonospiculum bridge, lateral view; 50 – same, dorsal view; 51 – bursa copulatrix with cells, lateral view; 52 – spermatheca.