Diclidophlebia venosa BURCKHARDT & DROHOJOWSKA, 2024

Diclidophlebia venosa BURCKHARDT & DROHOJOWSKA sp. nov.

Fig. 1A, B View Fig , 2 View Fig

LSID: urn:lsid:zoobank.org:act:5BB9A3FC-3E02- 4746-A423-9272D3A3DEA6

Etymology: From the Latin adjective venosus (1 st /2 nd declension) = full of veins, referring to the forked vein R 1.

Holotype: Male specimen, sample #24 ( GPAC) .

Paratypes: Two female specimens, samples #17(2), #17(3) ; one adult specimen without abdomen, sample #22 ( GPAC) .

Type locality: Dominican Republic, Cordillera Septentrional .

Description: Adult: Colouration. Head and thorax light brown. Antenna brown, segments 6–9 each with dark brown apex, segment 10 entirely brown. Mesoscutum with a median and each a submedian and sublateral longitudinal stripe on either side dark brown. Legs brown, apical metatibial spurs almost black. Forewing with light brown membrane and brown veins; apices of veins along wing margin each with conspicuous black spot; pterostigma greyish brown basally, light brown apically. Abdominal sclerites and terminalia brown, membrane greyish.

Structure. Head, in lateral view, weakly inclined (<45°) from longitudinal body axis ( Fig. 1 A View Fig ). Vertex trapezoidal, 1.8–2.5 times as wide as long along coronal suture; covered in granular microsculpture; curved down to genae without separation ( Fig. 2 A View Fig ). Genae evenly rounded, lacking processes; in the male the head is strongly compressed dorso-ventrally so that the genae stick out anteriorly looking like short genal processes ( Fig. 1 A View Fig , 2 A View Fig ). Compound eyes hemispherical. Antenna 10-segmented, 1.5 times as long as head width; relative length of flagellar segments as 1.0: 0.3: 0.3: 0.3: 0.3: 0.3: 0.2: 0.2; relative lengths of antennal segment 10 and terminal setae as 1.0: 1.2: 1.1. Pronotum transversely ribbon-shaped, 0.8 times as long as vertex along medial longitudinal body axis. Metapostnotum with low, laterally compressed tooth. Pro- and mesotibiae slender, not widening to apex ( Fig. 1 A, B View Fig , 2 B View Fig ). Metacoxa with long tubular, apically blunt meracanthus ( Fig. 1 B View Fig , 2 B View Fig ). Metatibia longer than metafemur, slightly widened apically; bearing (2–3)+(4–5) indistinctly grouped apical sclerotised spurs that are not on raised processes, without weakly sclerotised bristles ( Fig. 1 B View Fig , 2 B View Fig ). Both metatarsal segments relatively short, subequal in length. Forewing ( Fig. 1 A View Fig , 2 C – E View Fig ) oblong-oval; widest in the middle, 2.3–2.4 times as long as wide, membranous; apex narrowly rounded; vein C+Sc weakly curved, appearing to be slender and well delimited to cell but not clearly visible; costal break developed, close to apex of vein R 1; pterostigma wide, coriaceous basally, membranous apically; nodal line not developed; vein R slightly shorter than M+Cu; vein R 1 with one subapical branch, in one female the left forewing has two branches and in a specimen without abdomen both forewings have two branches but arranged asymmetrically; vein Rs relatively straight in basal four fifths, weakly curved towards costal margin in apical fifth; vein M distinctly longer than M 1+2; vein M 1+2 weakly curved; vein M 3+4 almost straight; vein Cu 1a straight in basal quarter, strongly curved in apical third; vein Cu 1b short, straight; cell cu 2 long; anal break adjacent to apex of vein Cu 1b; surface spinules fine, arranged in transverse rows, visible in cell cu 2 and in apical quarter of wing. Hindwing three quarter of forewing length; with 6–8 relatively evenly spaced costal setae distal to costal break. Male terminalia as in Fig. 1A View Fig , 2F View Fig ; proctiger tubular, weakly convex posteriorly; subgenital plate elongate, beset with a few moderately long setae in apical two thirds, ventrally; paramere slightly shorter than proctiger, lamellar, strongly narrowed in apical quarter into digitiform process. Female terminalia, in lateral view, cuneate ( Fig. 2 G View Fig ); proctiger almost straight dorsally except for a shallow indentation in the middle, pointed apically, with several moderately long hairs in the middle ( Fig. 2 G View Fig ); subgenital plate slightly shorter than proctiger bearing moderately long setae in the middle; ventral margin hardly curved; irregularly narrowing to pointed apex ( Fig. 2 G, H View Fig ).

Measurements (in mm): Head width 0.66; antenna length 0.8; forewing length 1.7–1.9; metatibia length 0.5; male proctiger length 0.29; paramere length 0.18; female proctiger length 0.43.

Comments: Diclidophlebia venosa fits the concept of Diclidophlebia redefined by BURCKHARDT et al. (2023) by the pterostigma of the forewing, which is leathery in the proximal half and membranous in the distal half (a synapomorphy of the genus), and the presence of well-sclerotised apical spurs on the metatibia arranged in two groups. Another diagnostic character of Diclidophlebia sensu BURCKHARDT et al. (2023) , the broadened C+Sc vein of the forewing that is not clearly demarcated from the neighbouring cell, is not clearly visible in the specimens examined. Diclidophlebia venosa differs from all seven extant Diclidophlebia species recognised by BURCKHARDT et al. (2023) in the presence of the subapically forked vein R 1, which is unusual in psyllids and, as far as known, unique in Liviinae . In two of the four specimens at hand a second fork on R 1 is developed on one or on both wings, but then asymmetically. The asymmetrical nature of this extra-vein suggests that this constitutes an abnormal feature. Specimens with abnormal venation are sometimes also found in extant psyllids. Diclidophlebia venosa resembles D. fremontiae ( KLYVER, 1930) in the unpigmented, elongate oval forewings with the vein M longer than M 1+2, and with the long cell cu 1, the apically barely expanded metatibia with apical spurs not located on processes, and its occurrence in the New World. These characters indicate a close phylogenetic relationship between the two species. Diclidophlebia venosa sp. nov. differs from D. fremontiae in the presence of black spots at the apices of the veins along the forewing margin, the greater number of metatibial spurs (1+(2–3) in the latter), the longer male subgenital plate, the apically stronger and more abruptly narrowed paramere and the longer female terminalia without the upturned apex of the proctiger. The six Old World species have either pigmented forewings ( D. eastopi VONDRÁČEK, 1964 , D. excetrodendri ( LI & YANG, 1991) , D. harrisoni OSISANYA, 1969 and D. oceanica ( CRAWFORD, 1919)) , the vein M 1+2 distinctly longer than M ( D. eastopi , D. leptonychiae BURCKHARDT et al., 2006 and D. oceanica ) or have an apically clearly widened metatibia with apical spurs on processes ( D. eastopi , D. harrisoni , D. leptonychiae , D. oceanica , and Diclidophlebia xuani MESSI in MESSI et al. 1998).