Gergithoides devyveri, 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 : 17-23

Gergithoides devyveri sp. nov.

urn:lsid:zoobank.org:act:E9D5D161-26D3-4AAF-BFF6-94DFBDFA6073

Figs 1 , 2A , 4 , 9–11

Diagnosis

Gergithoides devyveri sp. nov. can be recognized by:

(1) the yellow basal patch of tegmina (“shoulder”), contrasting with the olivaceous brown general colour of the insect ( Figs 9A , 11 );

(2) the lateroventral trispinose processes of aedeagus (lvp), asymmetrical: left process with anterodorsal spine strongly elongate, strongly curved mesodorsad on dorsal lobe, anteroventral spine much shorter, parallel to anterodorsal spine, posterior spine abruptly recurved ventrocephalad with point directed cephalad ( Fig. 10H–K ); right process with anterodorsal spine strongly elongate, regularly curved dorsoposteriorly, anteroventral spine much shorter, parallel to anterodorsal spine, posterior spine abruptly curved ventrad more or less at right angle ( Fig. 10I );

(3) posterior margin of pygofer strongly rounded around ventral ⅓ in lateral view (Py – Fig. 10A );

(4) anal tube slightly longer than wide in midline in dorsal view, dorsoventrally flattened with sides bisinuate, diverging to midlength and with apical margin bisinuate in dorsal view, with apicolateral angles rounded (An – Fig. 10D ).

Differential diagnosis

The closest species, sharing the character of a trispinose lateroventral process of the aedeagus with anterodorsal spine very elongate, is G. gnezdilovi Constant & Pham, 2017 described from Bidoup-Nui Ba National Park in Central Vietnam ( Constant & Pham 2017). However, G. devyveri can be differentiated by a wider vertex, 2.2 times as wide as long in midline, while it is only 1.65 times as wide as long in G. gnezdilovi ( Constant & Pham 2017: fig 1a), the absence of a transverse, wide, dark band on tegmina, well visible in G. gnezdilovi ( Constant & Pham 2017: fig 1a, c), the left trispinose process of aedeagus (lvp) with anterodorsal spine strongly elongate, strongly curved mesodorsad on the dorsal lobe, while it is directed dorsad in G. gnezdilovi ( Constant & Pham 2017: fig. 2d), and the right trispinose posterior spine moderately long and curved ventrad more or less at a right angle, while the corresponding spine is strongly, acutely recurved cephalad in G. gnezdilovi ( Constant & Pham 2017: fig. 2f).

Etymology

The species epithet is a patronym dedicated to Dr Bernard Devyver, surgeon in Namur ( Belgium) in acknowledgement for operating JC in 2015 after a severe indoor rock climbing accident, hence allowing the continuation of the fieldwork in SE Asia and Australia.

Material examined

Holotype VIETNAM • ♂ (dissected); Thừa Thiên-Huế Province, Bach Ma National Park; Rhododendron trail ; 19 Mar. 2023; 1158 m a.s.l.; V.T. Trung leg.; VNMN.

Paratypes VIETNAM • 1 ♀; Thừa Thiên-Huế Province, Bach Ma National Park, surroundings of Hotel Morin ; 16.2° N, 107.85° E; 1350–1400 m a.s.l.; 23–28 May 2014; L. Bartolozzi, G. Chelazzi, A. Bandinelli, S. Bambi and F. Fabiano leg.; n° Magazz. 2978; MZUF • 2 ♂♂, 1 ♀; Thừa Thiên-Huế Province, Bach Ma National Park ; 16°11′44″ N, 107°50′44″ E; 1200–1300 m a.s.l.; 22 May 2023; roadside; J. Constant and L. Semeraro leg.; I.G.: 34.640; RBINS • 1 ♂, 3 ♀♀; 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 ♂, 3 ♀♀; same collection data as for preceding; VNMN • 2 ♂♂, 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.; 16 Sep. 2024; by net; Hoai T.T. Nguyen leg.; AU 00499; VNMN .

Description

MEASUREMENTS AND RATIOS. LT: ♂ (n = 5): 5.9 mm (5.4–6.3), ♀ (n = 5): 6.5 mm (6.3–6.6); LT/BB = 1.47; LTg/BTg = 1.70; LW/BW = 2.06; BV/LV = 2.23; LF/BF = 1.22.

HEAD ( Fig. 9A–E ). Vertex longer in midline than broad, yellow brown with margins carinate; anterior margin convex, posterior one concave, angular in middle, and lateral converging anteriorly; disc excavate with obsolete median line. Side of head yellowish. Frons elongate and rugulose, dark reddish brown; median carina yellowish, narrowly margined with a black line, extending from dorsal margin, fading down to frontoclypeal suture; row of yellowish tubercles on black background along dorsal and lateral margins extending to level of base of eyes; lateral margins yellowish under eyes, the yellowish line often marginated by inner thin black line. Clypeus dark brown with basilateral yellowish spot and black on sides and apex, slightly elevated medially. Labium blackish brown with last segment longer than broad and shorter than penultimate one. Antennae blackish brown with scape short, ring-shaped and pedicel bulbous.

THORAX ( Fig. 9A–E ). Variegated olivaceous brown and blackish. Pronotum very short, about half length of mesonotum in midline, with median carina; anterior and posterior margins carinate; disc rugulose, concave with an impressed point on each side of median carina; row of yellowish tubercles along anterior margin extending on paranotal fields to level of base of eyes; another oblique row of 3–4 yellowish tubercles on each side of disc, parallel to anterior margin. Mesonotum short, slightly coriaceous with yellowish median carina; transverse carina along anterior margin yellowish; 2–4 yellowish blunt tubercles grouped at each external angle; yellowish suffused marking on each side of scutellum; apex of scutellum elevated and brown. Tegulae olivaceous brown.

TEGMINA ( Fig. 9A–C, E ). Strongly convex; about 1.2 times as long as broad when taken together in dorsal view; slightly concave at basicostal angle; subcoriaceous with dense reticulum of slightly raised veins and veinlets; main veins barely distinct basally; large yellowish mark at base, remaining portion yellowish brown with brown to black irregular markings, especially along inner margin of cells, making the insect look olivaceous from a distance.

HIND WINGS ( Fig. 9F ). Brown, unilobed, with veins slightly 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 sinuate, distal margin rounded.

LEGS ( Fig. 9A–D ). Elongate and slender, pro- and mesofemora slightly flattened, wider and slightly shorter than corresponding tibiae; brown with trochanters, base of femora and line along externoventral margin of femora black; black-brown line on ventral carinae of tibiae; base and apex of tibiae, claws and apex of metatibial spines black-brown; pro- and mesofemora with pale yellow tubercles. Metatibiae with 2 lateral spines on apical ⅓ and 7 apical spines. Metatibiotarsal formula: (2) 6 /8–9 / 2.

ABDOMEN ( Fig. 9B ). Sternites yellow brown with middle, posterior and lateral areas darker, often with irregular paler markings on sides.

MALE TERMINALIA ( Fig. 10 ). Pygofer (Py – Fig. 10 A–D ) 2.4 times as high as broad in lateral view, with posterior margin strongly rounded around ventral ⅓; nearly circular in caudal view; ventral margin rounded in lateral view. Gonostyli (G – Fig. 10A–C ) rather short in lateral view, with ventral margin broadly rounded, posterior margin more narrowly, dorsal margin strongly oblique basally to neck of capitulum, more posteriorly forming a straight angle with neck of capitulum; capitulum (ca) with elongate neck, narrow and directed dorsad in lateral view, curved mesad in posterior view; apical portion anteroposteriorly laminate, elongate in caudal view, bearing one dorsal tooth, one tooth at inner angle and one tooth pointing anteroventrally at anterobasal angle, followed posterad by a lateral lamina curved ventrad looking like an additional tooth in caudal view.Anal tube (An – Fig. 10A–D ) about 1.1 times as long as wide in midline in dorsal view, dorsoventrally flattened with sides bisinuate, diverging to midlength, apical margin bisinuate in dorsal view, with lateral angles rounded and slightly surpassing median lobe; in lateral view, anal tube curved ventrally; apicolateral angles roundly projecting lateroventrally. Aedeagus strongly curved posterodorsally, rather simple ( Fig. 10E–L ). Lateroventral processes of aedeagus (lvp) at basal half showing 3 spines and asymmetrical; left process with anterodorsal spine strongly elongate, strongly curved mesodorsad on dorsal lobe, anteroventral spine much shorter, curved cephalodorsad, parallel to anterodorsal spine, posterior spine moderately long and abruptly recurved ventrocephalad with point directed cephalad ( Fig. 10 H–K ); right process with anterodorsal spine strongly elongate, regularly curved dorsoposteriorly, anteroventral spine much shorter, curved cephalodorsad, parallel to anterodorsal spine, posterior spine moderately long and abruptly, moderately curved ventrad more or less at a right angle ( Fig. 10I ); periandrium with lateral lobe (ll) foliaceous and reflexed cephalad on each side in distal portion, with right one slightly more developed and projecting slightly further laterally than left one; aedeagus (ae) largely membranous and with 2 median processes side by side pointed apically; ventral lobe of periandrium (vl) broad with apical margin rounded.

Biology

Gergithoides devyveri sp. nov. was collected in March, May and September on lower vegetation and bushes ( Fig. 11 ), in moist evergreen tropical mountain forest, only at higher altitudes between about 1100 and 1400 m a.s.l. in Bach Ma National Park, at the “summit” area ( Figs 2A (5), 4B) as well as at “roadside” ( Figs 2A (4), 4A) collecting sites.

Distribution

Vietnam: Thừa Thiên-Huế Province, Bach Ma National Park ( 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. 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. 9. Gergithoides devyveri 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. Right hind leg, ventral view. H. Metatarsus and apex of metatibia, ventral view.

Fig. 10. Gergithoides devyveri sp. nov., holotype, ♂ (VNMN), terminalia. A–D. Pygofer, anal tube and gonostyli. A. Left lateral view. B. Caudal view. C. Posterolateral view. D. Dorsal view. E–N. Aedeagus. E. Posteroventral view. F. Anterodorsal view. G. Dorsal view. H. Left lateral view. I. Right lateral view. J. Left laterodorsal view. K. Right laterodorsal view. L. Ventral view. M. Left posterolateral view. N. Right posterolateral view. Abbreviations: see Material and methods.

Fig. 11. Gergithoides devyveri sp. nov., Bach Ma National Park. A–D. Summit trail, specimens, 11–13 May 2023. E–H. Rhododendron trail, 14 May 2023. E–G. Specimens. H. Microhabitat.