Diaphorina pfanderae Aléné and Burckhardt, 2021

Aléné, Désirée Chantal, Latar Vernyuy, Nina, Djiéto-Lordon, Champlain & Burckhardt, Daniel, 2021, Diaphorina pfanderae Aléné and Burckhardt sp. nov. (Hemiptera: Psylloidea: Psyllidae) and its association with ants on Ozoroa pulcherrima (Anacardiaceae), Journal of Natural History 55 (27 - 28), pp. 1649-1662 : 1653-1657

Diaphorina pfanderae Aléné and Burckhardt sp. nov.

urn:lsid:zoobank.org:act:227B3542-998A-49F7-B39B-8D1D1934C616

( Figures 3–5 )

Material

Holotype male, CAMEROON: West Region, Department of Noun , vicinity of Koutaba , near Tchouffa village , 5.6702°N, 10.7884°E, 1230 m, 29 October 2019, Ozoroa pulcherrima (D.C. Aléné) ( NHMB, dry mounted) . – Paratypes. CAMEROON: 1 male, 2 females, same data as holotype but ( NHMB, dry and slide mounted); 3 immatures, 2 mummies, same data as holotype but 24 January 2016 ( NHMB, slide mounted, in 70% ethanol) .

Diagnosis

Adult. Adult body mostly covered with microscopic setae. Genal processes conical, subacute, 0.7–0.8 times as long as vertex along coronal suture. Fore wing 2.2–2.3 times as long as wide; oval, widest slightly distal to the middle; fore margin weakly and relatively evenly curved in distal half; brown to dark brown with whitish pattern as follows: band along fore margin including vein C+ Sc, most of cell c+ sc and pterostigma, irregular band in cell m2 reaching wing margin, each an apical patch of variable size in cells r1, r2, m1 and cu1, and several uneven spots in cell cu2; veins brown to dark brown except for tips which are lighter. Male proctiger with posterior margin, in profile, moderately produced, widest in basal third, irregularly rounded. Paramere, in profile, blade-shaped, weakly curved along hind margin, narrowly rounded apically; outer face with moderately long setae in caudal half; inner face bearing subapical sclerotised tooth, covered with long thick, densely spaced setae in apical quarter, and slightly finer and more spaced setae elsewhere, except for basal quarter which is glabrous. Female proctiger with dorsal margin almost straight, apex narrowly rounded, subacute, with long setae surrounding circumanal ring, a submedian longitudinal row of long setae on either side in apical half and short, densely spaced spines in apical half. Female subgenital plate conspicuously angular ventrally, pointed apically. – Fifth-instar immature: Last-instar immature with antennal segment 3 bearing a lanceolate seta near each of the two basal rhinaria. Caudal plate narrowly rounded, indented posteriorly; margin with a few inconspicuous scattered lanceolate setae and 4–5 long robust setae on either side of medial indentation. Outer circumanal ring small, interrupted medially at fore and hind margins, consisting of a single row of oval pores.

Description

Adult. Colouration. Dark brown to black dorsally, light greyish brown ventrally ( Figure 3 (a, b)). Head brown with darker coronal suture and margins of vertex and sometimes tips of genal processes; ocelli reddish or grey, compound eyes reddish or greyish brown ( Figure 3 (c)). Antenna pale yellow, segment 1 brown, segment 2 ochreous, segments 9 and 10 almost black, and apices of segments 4, 6 and 8 brown ( Figure 3 (d)). Mesopraescutum and mesoscutum with indistinct lighter longitudinal bands.Legs with dark brown coxae and femora, and yellowish tibiae and tarsi. Fore wing ( Figure 3 (e)) brown to dark brown with whitish pattern as follows: band along fore margin including vein C+ Sc, most of cell c+ sc and pterostigma, irregular band in cell m2 reaching wing margin, each an apical patch of variable size in cells r1, r2, m1 and cu1, and several uneven spots in cell cu2; veins brown to dark brown except for tips which are lighter. Hind wing whitish. Abdominal sternites with an indistinct median light brown band and a fine brown longitudinal submedian band on either side. Terminalia dark brown to black.

Structure. Integument of head, legs and terminalia beset with short moderately dense pilosity; that of thorax and abdomen (except for terminalia) lacking macroscopic setae, with fine granular microsculpture. Head ( Figure 3 (c)) with rectangular vertex, 0.5 times as long as wide; genal processes conical, subacute, 0.7–0.8 times as long as vertex along coronal suture. Antenna ( Figure 3 (d)) 0.7–0.8 times as long as head width; relative lengths of segment 10 and the two terminal setae 1.0:0.9:0.4. Rostrum 0.6 times as long as head width. Metatibia 0.9–1.0 times as long as head width, bearing an open crown of 8 sclerotised apical spurs. Fore wing ( Figure 3 (e)) 3.1–3.3 times as long as head width, 2.2– 2.3 times as long as wide; oval, widest slightly distal to the middle; fore margin straight in proximal half, weakly and relatively evenly curved in distal half; pterostigma moderately long and broad, vein R about twice as long as vein M+ Cu, vein Rs evenly curved towards fore margin, cell m1 larger than cell cu1, cell cu1 about as high as long; surface spinules coarse, present in all cells covering membrane up to veins, densely spaced. Hind wing almost as long as fore wing, vein R + M+ Cu indistinctly splitting into R + M and Cu; costal margin with 4 straight setae proximal to costal break and 8–11 weakly curved, ungrouped setae distal to costal break. Male terminalia as in Figure 4 (a–c). Proctiger 0.5 times as long as head width; beset with moderately long setae in apical two-thirds becoming denser apically; posterior margin, in profile, produced, widest in basal third, irregularly rounded. Subgenital plate subglobular; with an irregular row of moderately long setae along dorsal margin proximally and a group of sparsely spaced, moderately long setae caudally; in profile with sinuous dorsal margin and evenly rounded ventral margin. Paramere, in profile, blade-shaped, weakly curved along hind margin, narrowly rounded apically; outer face with moderately long setae in caudal half; inner face bearing subapical sclerotised tooth, covered with long, thick, densely spaced setae in apical quarter, and slightly finer and more spaced setae elsewhere, except for basal quarter which is glabrous. Basal segment of aedeagus straight in distal half, lacking bulge on anterior face; medial segment straight, weakly expanded basally and tapering to apex; distal segment oval, sclerotised end tube of ductus ejaculatorius short, weakly sinuous. Female terminalia cuneate ( Figure 4 (d, e)). Proctiger 0.9 times as long as head width, dorsal margin almost straight, apex narrowly rounded, subacute, with long setae surrounding circumanal ring, a submedian longitudinal row of long setae on either side in apical half and short, densely spaced spines in apical half; circumanal ring 0.3 times as long as proctiger, oval, consisting of two rows of unequal pores, the outer ones almost circular, the inner one oval. Subgenital plate 0.9 times as long as proctiger, ventral margin with conspicuous angle in the middle, pointed apically, covered by sparse short setae in apical two-thirds.

Measurements (in mm; 1 ♂, 1 ♀). Body length 2.3–2.8; head width 0.64–0.66; antenna length 0.48–0.50; fore wing length 2.00–2.20; male proctiger length 0.32; paramere length 0.30; length of distal two segments of aedeagus 0.20; female proctiger length 0.60.

Fifth-instar immature. Colouration ( Figure 5 (d)). Dorsal sclerites dark brown or almost black, membranes whitish. Eyes greyish red. Antennal segments 1 and 2 brown, segment 3 yellowish with dark apex. Tip of rostrum dark brown. Wing pads dark brown medially and slightly lighter distally. Ventral sclerites pale brown, caudal plate becoming darker caudad.

Structure. Body ( Figure 5 (a)) oval, 1.1–1.2 times as long as wide; integument sparsely covered in microscopic setae. Antenna 3-segmented, 0.4–0.5 times as long as fore wing pad; segment 3 bearing 4 postero-ventral rhinaria; 1 lanceolate seta present near each of the basal 2 rhinaria and 1 (rarely none) in the middle between base of segment and most proximal rhinarium. Thoracic tergites large. Fore wing pad with large humeral lobe, anteriorly reaching posterior third of eye, irregularly, narrowly rounded; lateral margin weakly curved anteriorly and posteriorly, almost straight medially, beset with sparsely spaced microscopic lanceolate setae. Caudal plate ( Figure 5 (c)) 0.6 times as long as wide, narrowly rounded, indented posteriorly; margin with a few inconspicuous scattered lanceolate setae and 4–5 long robust setae on either side of medial indentation. Anus ventrally near caudal margin; outer circumanal ring ( Figure 5 (e)) small, kidney-shaped, interrupted medially at fore and hind margins, consisting of a single row of oval pores.

Measurements (in mm; 3 specimens). BL 1.38–1.48; AL 0.30–0.32.

Egg. Colouration. Whitish when laid, gradually turning yellow when matured.

Structure ( Figure 4 (f)). Oval, narrowly rounded at base, tapering and blunt apically; pedicel short.

Host plant

Ozoroa pulcherrima (Schweinf.) R.Fern. and A.Fern. (Anacardiaceae) .

Distribution

Cameroon (West Region).

Etymology

Dedicated to our friend Isabelle Zürcher-Pfander, Collection Manager at the NHMB, in recognition of her continuous support of our psyllid studies.

Comments

Diaphorina comprises 77 described species worldwide, of which 56 occur in the Afrotropical region (including the Arabian Peninsula) and 30 in South Africa ( Malenovský and Burckhardt 2014; Ouvrard 2020). Diaphorina pfanderae shares with the Afrotropical D. albomaculata Capener, 1970 , D. enderleini , D. natalensis (Pettey, 1924) , D. solani Capener, 1970 and D. tenebrosa Capener, 1970 the following morphological characters: adults: the short, evenly conical, pointed genal processes and the oval fore wings that are widest near the middle and have a weakly, relatively evenly curved fore margin in apical half; immatures: a postero-medially indented caudal plate and a very small, partly open circumanal ring consisting of a single row of pores, sometimes the circumanal ring is completely reduced. This set of characters may indicate close phylogenetic relationships and is used here to define the putatively monophyletic Diaphorina albomaculata species group.

Diaphorina citri differs from the members of the D. albomaculata group in the longer, apically subacute genal processes and the fore wings that are widest in the apical fifth, with the fore margin almost straight in basal four-fifths and strongly bent at apical fifth (rather than widest near the middle with curved fore margin).

Diaphorina pfanderae differs from the other members of the D. albomaculata group in details of the fore wing pattern, of the shape of the male and female terminalia and of the chaetotaxy of the last-instar immatures (see identification key below). The fore wing pattern of D. pfanderae is characterised by the mostly homogeneous dark brown colour covering most of the wing with a conspicuous light band in cell m2 stretching from the middle to the distal margin of the cell; in the other species either the dark colour is patchier ( D. enderleini , D. natalensis and D. solani ) or cell m2 has no light band ( D. tenebrosa ) or only a light patch which does not reach the distal wing margin ( D. albomaculata ). Diaphorina pfanderae and D. albomaculata share morphologically similar parameres and female terminalia but the former species has slightly longer genal processes, more elongate fore wings and a posteriorly more produced male proctiger. The immatures of D. pfanderae and D. albomaculata have only microscopic lanceolate setae on the margins of the wing pads, whereas the other three species possess macroscopic lanceolate setae, well visible at 50 times magnification. Immatures of D. pfanderae have 4–5 long robust setae on either side of medial indentation along the margin of the caudal plate, while in D. albomaculata there are 7–12 lanceolate setae on either side.

Figures

Figure 3. Diaphorina pfanderae Aléné and Burckhardt sp. nov., adults. (a) Habitus, in profile, of male; (b) habitus, in profile, of female; (c) head, dorsal view; (d) antenna; (e) fore wing.

Figure 4. Diaphorina pfanderae Aléné and Burckhardt sp. nov., terminalia and egg. (a) Male terminalia, in profile; (b) inner face of paramere; (c) distal two segments of aedeagus; (d) female terminalia, in profile; (e) section of circumanal ring; (f) egg, in profile.

Figure 5. Diaphorina pfanderae Aléné and Burckhardt sp. nov., egg and immatures. (a) Habitus of fifth instar, left side; (b) egg clusters and immatures; (c) caudal plate; (d) colony covered in honeydew; (e) circumanal ring.