Ceratogergithus pictus, Constant & Pham, 2025

Constant, Jérôme & Pham, Hong Thai, 2025, Issid planthoppers from Bach Ma and Phong Dien in Central Vietnam: (II) Tribe Hemisphaeriini (Hemiptera: Fulgoromorpha: Issidae), European Journal of Taxonomy 994 (1), pp. 1-76 : 10-16

Ceratogergithus pictus sp. nov.

urn:lsid:zoobank.org:act:B80F7B58-058C-487C-82B2-687E44357749

Figs 1–3 , 4B , 5–8

Diagnosis

Ceratogergithus pictus sp. nov. can be recognized by:

(1) the robust shape of the laterodorsal spine of the hind margin of the pygofer, wide and moderately elongate (Py – Fig. 7A );

(2) the rather short gonostyli, about 1.4 times as long as high (without capitulum) in lateral view (G – Fig. 7A );

(3) the laterodorsal process of the periandrium very narrow and elongate, twisted and strongly S-shaped in lateral view (ldp – Fig. 7E–L );

(4) the lateroventral process of the aedeagus with posterior portion elongate, pointed apically, sinuate in lateral view, and curved dorsomesad, and with the anterior portion strongly elongate and narrow, moderately curved (following curvature of aedeagus), pointed apically and reaching base of aedeagus (lvp – Fig. 7E–L ).

Differential diagnosis

The closest species is Ceratogergithus pseudotessellatus ( Che, Zhang & Wang, 2007) , described from Hainan Island ( Che et al. 2007). However, the latter species can be differentiated by the characters of the male terminalia (see Che et al. 2007: figs 55–59), with a thinner and more elongate process of the posterior margin of the pygofer, more elongate gonostyli (1.7 times as long as high in lateral view) and the much shorter, less strongly sinuate, laterodorsal processes of the periandrium.

Etymology

The species epithet ‘ pictus ’ is a Latin adjective meaning ‘painted’. It refers to the beautiful colour pattern of the species.

Material examined

Holotype VIETNAM • ♂ (dissected); Thừa Thiên-Huế Province, Bach Ma National Park , pheasant trail; [16°13′38″ N, 107°51′20″ E]; 6 Mar. 2023; by net; V.T. Trung leg.; VNMN.

Paratypes VIETNAM • 1 ♀; same collection data as for holotype; 2022; VNMN • 2 ♀♀; Thừa Thiên-Huế Province, Bach Ma National Park, Xue Su ; [16°14′10″ N, 107°52′44″ E]; 2022; near stream; V.T. Trung leg.; VNMN • 1 ♂, 11 ♀♀; Thừa Thiên-Huế Province, Bach Ma National Park, near ranger station ; 16°08′37″ N, 107°49′36″ E; 300–600 m a.s.l.; 18 May 2023; J. Constant and L. Semeraro leg.; I.G.: 34.640; RBINS • 4 ♀♀; same collection data as for preceding; VNMN • 2 ♀♀; Thừa Thiên-Huế Province, Bach Ma National Park, Yes Hue Eco ; 16°13′05″ N, 107°43′27″ E; 200–300 m a.s.l.; 17 May 2023; J. Constant and L. Semeraro leg.; I.G.: 34.640; RBINS • 2 ♀♀; Thừa Thiên-Huế Province, Bach Ma National Park , low altitude; 16°13′14″ N, 107°53′10″ E; 100–200 m a.s.l.; 17 May 2023; J. Constant and L. Semeraro leg.; I.G.: 34.640; RBINS • 2 ♂♂, 5 ♀♀; Thừa Thiên-Huế Province, Bach Ma National Park , summit; 16°11′18″ N, 107°50′56″ E; 1300–1400 m a.s.l.; 11–21 May 2023; J. Constant and L. Semeraro leg.; I.G.: 34.640; RBINS • 1 ♂, 12 ♀♀; Thừa Thiên-Huế Province, Bach Ma National Park , pheasant trail; 16°13′38″ N, 107°51′20″ E; 500–600 m a.s.l.; 10–20 May 2023; J. Constant and L. Semeraro leg.; I.G.: 34.640; RBINS • 2 ♀♀; same collection data as for preceding; VNMN • 1 ♀; Thừa Thiên-Huế Province, Bach Ma National Park , pheasant trail; 16°12′ N, 107°52′ E; daytime collecting; 12–17 Jul. 2011; J. Constant and J. Bresseel leg.; I.G.: 31.933; RBINS • 6 ♀♀; Thừa Thiên-Huế Province, Bach Ma National Park , summit; 16°12′ N, 107°52′ E; 15–16 Jul. 2011; daytime collecting; J. Constant and J. Bresseel leg.; I.G.: 31.933; RBINS • 1 ♀; Thừa Thiên-Huế Province, Bach Ma National Park , pheasant trail; 16°12′ N, 107°52′ E; 10–16 Apr. 2017; J. Constant and J. Bresseel leg.; I.G.: 33.447; RBINS • 1 ♂; Thừa Thiên-Huế Province, Bach Ma National Park , pheasant trail; 16°13′38″ N, 107°51′20″ E; 350-600 m a.s.l.; 18 Oct. 2024; J. Constant, L. Semeraro and Hoai T.T. Nguyen leg.; I.G.: 34.893; RBINS • 1 ♂, 4 ♀♀; Thừa Thiên-Huế Province, Bach Ma National Park, ranger station , Nam Dong District; 16°08′37″ N, 107°49′36″ E; 150–500 m a.s.l.; 19 Oct. 2024; J. Constant, L. Semeraro and Hoai T.T. Nguyen leg.; I.G.: 34.893; RBINS • 6 ♀♀; same collection data as for preceding; VNMN • 1 ♂; Thừa Thiên-Huế Province, Bach Ma National Park, stairs going up to Hai Vong Dai ; 16°11′53.77″ N, 107°51′26.92″ E; 1272 m a.s.l.; May 2023; by net; Hoai T.T. Nguyen leg.; AU 00499; VNMN .

Other material

VIETNAM • 1 ♀; Vietnam, Thừa Thiên-Huế Province, Phong Dien District; 16°30′27″ N, 107°16′05″ E; 350–400 m a.s.l.; 23 May 2023; J. Constant and L. Semeraro leg.; I.G.: 34.640; RBINS .

Description

MEASUREMENTS AND RATIOS. LT: ♂ (n = 4): 5.4 mm (5.2–5.6), ♀ (n = 5): 5.9 mm (5.5–6.2); LT/BB = 1.36; LTg/BTg = 1.61; LW/BW = 2.16; BV/LV = 1.79; LF/BF = 0.78.

HEAD ( Fig. 6A–E ). Vertex distinctly wider than long in midline, brown in anterior portion and whitish yellow to bright yellow in posterior portion with lateral margins weakly carinate; anterior and posterior margins smooth, subparallel and curved; disc shallowly excavate. Side of head yellow with dark brown marking from eye to level of transverse fascia of frons. Frons smooth, convex, about 1.3 times as wide under antennae as long in midline, with lateral margins distinctly curved; upper ⅓ brown, lower ⅔ yellowish white to bright yellow with transverse, complete, curved, dark brown to black fascia in middle. Clypeus black-brown with apical yellowish spot and yellow on sides. Labium brown with last segment longer than broad, and shorter than penultimate one. Antennae yellowish with scape short, ring-shaped and pedicel bulbous.

THORAX ( Figs 6A–E , 8B–E ). Colour varies individually from pale to dark form. Pronotum very short, about 0.4 times length of mesonotum in midline, smooth with 2 impressed points on disc; anterior margin carinate; brown with paranotal lobes with broad black band along ventral margin. Mesonotum triangular, smooth; transverse carina along anterior margin; in pale form: brown with large, transverse marking on disc in anterior half, not reaching lateral angles; in dark forms: black with anterolateral angles brown. Tegulae brown.

TEGMINA ( Figs 6A–E , 8B–E ). Strongly convex; about 1.15 times as long as wide when taken together in dorsal view; sides regularly rounded, apex rounded; smooth with weakly distinct reticulum of veins and veinlets; mains veins barely distinct basally; brown with bright yellow markings to black with whitish yellow markings or even entirely black. Bright yellow/whitish markings more or less developed, at maximum as follows: elongate basicostal marking, more or less elongate marking posterior to basal cell, transverse marking dorsally at midlength, at level of clavus, elongate, oblique marking at midlength, originating from “costal cell”, narrow band along costal margin on posterior third, followed cephalad, along postclaval margin, by a regularly spaced series of up to five bands, each getting shorter and more oblique towards the anterior; in palest forms, blackish markings between bright yellow markings on distal portion of tegmina.

HIND WINGS ( Fig. 6F ). Brown, unilobed, with veins darker than cells; elongate, slightly shorter than tegmina. Venation reticulate with main longitudinal veins distinct basally (C, ScP+R, MP, CuA); numerous cross-veinlets. Anal area obsolete. Costal and cubital margins weakly sinuate, distal margin rounded.

LEGS ( Fig. 6A–D, G–H ). Elongate and slender, with pro- and mesofemora slightly flattened and wider than corresponding tibiae. Pro- and mesocoxae black with base and apex yellow; all trochanters yellow; profemora black with 2 yellow rings; mesofemora yellow with irregular black markings; pro- and meso tibiae with external margin lined with dark brown to black; pro- and mesotarsi yellow with black claws; metafemora dark brown to black; metatibiae yellow with base infuscate and lateral and apical spines black; metatarsi yellow with basal segment black ventrally along posterior margin. Metatibiae with 2 lateral spines on apical half and 6 apical spines. Metatibiotarsal formula: (2)6 / 8/ 2.

ABDOMEN ( Fig. 6B ). Sternites yellowish with basilateral brown marking on each side.

MALE TERMINALIA ( Fig. 7 ). Pygofer (Py – Fig. 7A–D ) higher than broad in lateral view, with posterior margin bisinuate, with a massive spinose process at laterodorsal angle; ventral margin rounded in lateral view; circular in caudal view. Gonostyli (G – Fig. 7A–B, D ) rather short, about 1.4 times as long as high (without capitulum) in lateral view, ventral margin broadly rounded, apical margin rounded and dorsal margin sinuate; capitulum (ca) with short, wide neck, twisted, with mesoposterior margin rounded and anterolateral margin with strong tooth and margin concave above tooth. Anal tube (An – Fig. 7A–D ) moderately long, about 1.15 times as long in midline as wide slightly before midlength in dorsal view; dorsoventrally flattened with lateral margins downcurved, suboval with apical margin broadly rounded in dorsal view; in lateral view, curved at basal ⅓ (level of anal opening). Aedeagus moderately curved posterodorsally, complex, with strong median, dorsal, spinose process (dsp) directed caudad ( Fig. 7E– L ). Periandrium with moderately developed, rounded basal lobe (bl) covering base of lateral process (lp) and of laterodorsal process (ldp); lateral process of periandrium (lp) very slender, pointed, not reaching half length of aedeagus; laterodorsal process of periandrium (ldp) very narrow and elongate, twisted and strongly S-shaped in lateral view, with distal portion slightly dilated before ending in acute point, generally directed posterodorsad with apex recurved ventrad; ventral lobe (vl) of periandrium slightly widening towards apex and with apical margin rounded; dorsal lobe of periandrium (dl) slightly shorter than aedeagus; aedeagus (ae) with 2 apical acute points directed posterodorsad; lateroventral process of aedeagus (lvp) with posterior portion elongate, pointed apically, sinuate in lateral view and curved dorsomesad, and with anterior portion strongly elongate and narrow, moderately curved (following curvature of aedeagus), pointed apically and reaching base of aedeagus, and with minute lateral spine at about midlength of process. Connective (co) slightly curved, with strongly developed tectiductus (te), subtriangular in lateral view.

Biology

Ceratogergithus pictus sp. nov. was collected between March and May and in July and October in montane evergreen tropical forest as well as in lowland evergreen forest in Bach Ma, at altitudes between about 200 m and 1400 m a.s.l. In Bach Ma National Park, it was found at the following collecting site/ habitats ( Fig. 2A ): “Yes Hue Eco” ( Fig. 2A (1), B), “pheasant trail” ( Figs 2A (2), 3A), “low altitude” ( Figs 2A (3), 3B), “summit” ( Figs 2A (5), 4B) and “ranger station” ( Figs 2A (6), 5A), and in Phong Dien District ( Fig. 5B ). The species lives on the low vegetation and the specimens were usually found sitting on the main veins of leaves or on small twigs ( Fig. 8A–F ). A single specimen was observed at night, at the “ranger station” site in Bach Ma National Park, in a trophobiotic interaction with ants collecting the honeydew produced by the planthopper. The ants belong to an unidentified species of the genus Camponotus Mayr, 1861 ( Hymenoptera : Formicidae : Formicinae ) ( Fig. 8G–H ); the behaviour of the ants included antennal, palpal and proleg contact/palpation which are regarded as a way to stimulate honeydew production by the planthopper ( Bourgoin et al. 2023).

Distribution

Vietnam: Thừa Thiên-Huế Province, Bach Ma National Park and Phong Dien District ( Fig. 1 ).

Figures

Fig. 1. Map of the sampled localities in Thừa Thiên-Huế Province, Vietnam.

Fig. 2. Bach Ma National Park, habitats. A. Detailed map of the sampling areas (1 = ‘Yes Hue Eco’; 2 = ‘pheasant trail’; 3 = ‘low altitude’; 4 = ‘roadside’; 5 = ‘summit’; 6 = ‘near ranger station’. B. Typical habitat at ‘Yes Hue Eco’ sampling area, 17 May 2023.

Fig. 3. Bach Ma National Park, habitats. A. Typical habitat at ‘pheasant trail’ sampling area, 20 May 2023. B. Typical habitat at ‘low altitude’ sampling area, 15 May 2023.

Fig. 4. Bach Ma National Park, habitats. A. Typical habitat at ‘roadside’ sampling area, 21 May 2023. B. Typical habitat at ‘summit’ sampling area, 11 May 2023.

Fig. 5. Bach Ma National Park and Phong Dien District, habitats. A. Typical habitat at ‘ranger station’ sampling area, 18 May 2023. B. Typical habitat at Phong Dien sampling area, 23 May 2023.

Fig. 6. Ceratogergithus pictus sp. nov., dissected paratype, ♂ (RBINS). A. Habitus, dorsal view. B. Habitus, ventral view. C. Habitus, lateral view. D. Habitus, perpendicular view of frons. E. Habitus, anterolateral view. F. Right hind wing. G. Metatarsus and apex of metatibia, ventral view. H. Right hind leg, ventral view.

Fig. 7. Ceratogergithus pictus sp. nov., holotype, ♂ (VNMN), terminalia. A–D. Pygofer, anal tube and gonostyli. A. Left lateral view. B. Posterolateral view. C. Dorsal view. D. Caudal view. E–L. Aedeagus. E. Dorsal view. F. Anterodorsal view. G. Left lateral view. H. Posteroventral view. I. Ventral view. J. Left laterodorsal view. K. Left lateroventral view. L. Posterolateral view. Abbreviations: see Material and methods.

Fig. 8. Ceratogergithus pictus sp. nov., live specimens in Bach Ma National Park. A–C. Pheasant trail, 12 May 2023.D. Near ranger station, 18 May 2023.E–F. Summit trail, 20 May 2023.G–H. Trophobiosis with ant, Camponotus sp., near ranger station, 17 May 2023.