Ishiharanus dinhanus, 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 : 41-45

Ishiharanus dinhanus sp. nov.

urn:lsid:zoobank.org:act:9F31FA85-8686-4C0E-B235-5395E980DCD9

Figs 1 , 2A , 4B , 23–25

Diagnosis

Ishiharanus dinhanus sp. nov. can be recognized by:

(1) its colour pattern with the dorsum more or less dark brown with bright pale yellow markings: one on scutellum, three elongate ones on tegmina (basal, mediodorsal and anteapical) and some longitudinal lines along veins ( Figs 23 , 25 );

(2) the profemora colour being dark brown, turning more or less paler towards the apex ( Fig. 23B, E );

(3) the anal tube in dorsal view about 1.50 times as long in midline as wide, rather elongate with curved sides, and with apical margin deeply excavate and moderately bisinuate (An – Fig. 24D );

(4) the lateroventral processes of the aedeagus (lvp – Fig. 24G–R ) rather short, apically pointed, strongly sinuate with basal portion curved anterolaterad, then recurved anteromesad.

Differential diagnosis

The closest species, sharing some colouration characters of I. dinhanus sp. nov., is I. pulchellus sp. nov., which also shows pale yellow markings (in the paler forms) on the mesonotum and on tegmina. However, I. dinhanus is larger: LT: ♂: 5.1–5.2 mm, ♀ 5.5–5.9 mm, as compared to LT: ♂: 4.1–4.6 mm, ♀: 4.1–4.9 mm in I. pulchellus ; I. dinhanus shows dark brown profemora, turning slightly paler towards the apex ( Fig. 23B, E ), while the profemora are pale yellow with basal and apical black brown rings in I. pulchellus ( Fig. 29B, D ), and the brown tegmina show three bright, elongate, pale yellow markings but no concentric lines parllel to the posterior margin ( Fig. 23A, D ), while I. pulchellus shows round yellow markings on the disc of the tegmina that are more or less distinct (according to colour form, not visible in dark specimens) and two pale yellow concentric lines parallel to the posterior margin ( Figs 29A, C , 30A, C , 31A, C, G ). The two species also clearly differ in the shape of the lateroventral processes of the aedeagus, rather short, apically pointed, strongly sinuate and generally directed cephalad in I. dinhanus (lvp – Fig. 24G–R ), while in I. pulchellus they show two pointed, moderately curved, elongate portions, one directed cephalad and the other directed posteroventrad (lvp – Figs 32G–L , 33H–I ).

Etymology

The species epithet dinhanus is a Latinised form of the Vietnamese word ‘dinh’, meaning ‘summit’. It refers to the habitat of the species, the forest covering the summit of Bach Ma National Park.

Material examined

Holotype VIETNAM • ♂ (dissected); Bach Ma [National Park], summit ; 16°12′ N, 107°52′ E; 15–16 Jul. 2011; day [collecting]; J. Constant and J. Bresseel leg.; I.G.: 31.933; VNMN.

Paratypes VIETNAM • 1 ♂; Thua Thien-Hue [Province], Bach Ma [National Park]; 1300 m a.s.l.; 5 Jun. 2002; H.T. Ta leg.; VNMN • 1 ♂, 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 • 4 ♂♂, 2 ♀♀; 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 ♂; same collection data as for preceding; VNMN • 1 ♂, 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 00693; VNMN .

Description

MEASUREMENTS AND RATIOS. LT: ♂ (n = 5): 5.2 mm (5.1–5.2), ♀ (n = 3): 5.7 mm (5.5–5.9); LT/BB = 1.41; LTg/BTg = 1.66; LW/BW = 1.83; BV/LV = 1.91; LF/BF = 1.06.

HEAD ( Figs 23A–B, D–F , 25 ). Vertex broader than long in midline, brown with posterior margin weakly carinate; anterior margin convex, posterior one concave and lateral subparallel; disc shallowly excavate. Side of head brown with paler area under antenna. Frons elongate and smooth, brown turning paler towards frontoclypeal suture; clypeus blackish brown. Labium brown with last segment longer than broad, and shorter than penultimate one. Scape short, ring-shaped, brown; pedicel bulbous, brown.

THORAX ( Figs 23A–B, D–F , 25 ). Pronotum very short, about one third length of mesonotum in midline; anterior and posterior margins carinate; disc concave with an impressed point on each side of median line, with extremely narrow lateral fields behind eyes; blackish brown with disc brown. Mesonotum subtriangular, smooth, bright straw yellow with anterolateral angles dark brown. Tegulae brown.

TEGMINA ( Figs 23A–B, D, F , 25 ). Strongly convex; about 1.2 times as long as broad when taken together in dorsal view; slightly concave at basicostal angle; rugulose with dense reticulum of weakly raised veins and veinlets; main veins weakly distinct; dark brown with paler band along costal, postclaval and apical margins; veins in paler band bright straw yellow; in dark portion, 3 large, bright straw yellow markings: one elongate at base, including basal cell, one elongate, quite dorsal, at midlength, one smaller and weakly elongate in distal ⅓; some longitudinal veins marked with straw yellow, departing from basal marking and reaching to ⅔ of length.

HIND WINGS ( Fig. 23C ). 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 margin sinuate, cubital margin broadly rounded, distal margin rounded.

LEGS ( Fig. 23A–B, D–F ). Elongate and slender; femora wider and shorter than corresponding tibiae, dark brown turning more or less paler towards apex; pro- and mesotibiae pale yellowish with black line along externoventral carina; metatibiae yellowish brown with black spines. Metatibiae with 2 lateral spines on distal half and 6 apical spines. Metatibiotarsal formula: (2)6 /8 / 2.

ABDOMEN. Yellow brown.

MALE TERMINALIA. Pygofer (Py – Fig. 24A–F ) 2.7 times as high as long in lateral view; in lateral view, dorsal margin nearly horizontal followed posteriorly by rounded angle and strongly oblique slope leading to moderate, rounded angle protruding posterad at half height; ventral half slightly obliquely bisinuate; more or less circular in caudal view.Gonostyli (G – Fig.24A–F ) in lateral view with ventral margin broadly rounded, posterior margin rounded, projecting caudad, dorsal margin oblique, slightly bisinuate basally, then upcurved to neck of capitulum; capitulum (ca) with elongate, twisted neck, directed dorsocephalad in lateral view, subspatulate with upper angle rounded and directed mesodorsad in caudal view, with small, rather blunt tooth at anterodorsal angle followed posterad by carina on external side strongly recurved cephalad and ending in a tooth projecting cephalad in lateral view; in caudal view deep, round emargination under carina. Anal tube (An – Fig. 24A–F ) elongate; in dorsal view about 1.50 times as long in midline as wide, suboval in shape with apical margin strongly bisinuate, dorsoventrally flattened with posterior angles projecting posteroventrad; in lateral view, anal tube curved posteroventrad; apical margin deeply, roundly emarginate in caudal view. Aedeagus curved posterodorsally and twisted, rather simple, asymmetrical ( Fig. 24G–R ); lateroventral processes of aedeagus (lvp – Fig. 24G–R ) rather short, apically pointed, strongly sinuate, with basal portion curved anterolaterad, then recurved anteromesad; ventral lobe of periandrium (vl) well developed, shorter than aedeagus, shifted to the right and regularly tapering towards roundly truncate apex; dorsal lobe of periandrium (dl) shorter than aedeagus; aedeagus largely membranous with pair of elongate, roundly pointed processes. Connective (co) well developed and curved, with tectiductus (te) well developed, with widely open foramen.

Biology

Ishiharanus dinhanus sp. nov. ( Fig. 25 ) was collected in the months of May to July and in September on lower vegetation and bushes, in moist evergreen tropical mountain forest, only at higher altitude between about 1300 and 1400 m a.s.l. in Bach Ma National Park, at the “summit” area ( Figs 2A (5), 4B) collecting site.

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. 23. Ishiharanus dinhanus sp. nov., dissected holotype, ♂ (VNMN). A. Habitus, dorsal view. B. Habitus, ventral view. C. Right hind wing. D. Habitus, lateral view. E. Habitus, perpendicular view of frons. F. Habitus, anterolateral view.

Fig. 24. Ishiharanus dinhanus sp. nov., holotype, ♂ (VNMN), terminalia. A–F. Pygofer, anal tube and gonostyli. A. Left lateral view. B. Posterolateral view. C. Caudal view. D. Dorsal view. E. Ventral view. F. Posterodorsal view. G–R. Aedeagus. G. Left lateral view. H. Right lateral view. I. Caudal view. J. Ventral view. K. Left laterodorsal view. L. Right laterodorsal view. M. Right posterolateral view. N. Left lateroventral view. O. Right lateroventral view. P. Dorsal view. Q. Anterodorsal view. R. Left posterolateral view. Abbreviations: see Material and methods.

Fig. 25. Ishiharanus dinhanus sp. nov., live specimen from Bach Ma National Park summit, 19 May 2023, photographed in cage. A. Dorsal view. B. Laterodorsal view.

Fig. 29. Ishiharanus pulchellus sp. nov., dissected holotype, ♂ (VNMN). 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. 30. Ishiharanus pulchellus sp. nov., dissected paratype, ♂ (RBINS) from Bach Ma National Park, dark morph. 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.

Fig. 31. Ishiharanus pulchellus sp. nov., dissected paratype, ♂ (RBINS) from Kon Chu Rang National Park, pale morph. 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. Caudal view.

Fig. 32. Ishiharanus pulchellus sp. nov., dissected holotype, ♂ (VNMN), terminalia. A–D. Pygofer, anal tube and gonostyli. A. Left lateral view. B. Posterolateral view. C. Caudal view. D. Dorsal view. E–M. Aedeagus. E. Dorsal view. F. Ventral view. G. Left lateral view. H. Right lateral view. I. Left lateroventral view.J. Right lateroventral view. K. Left posterolateral view. L. Right posterolateral view. M. Caudal view. Abbreviations: see Material and methods.

Fig. 33. Ishiharanus pulchellus sp. nov., paratype, ♂ (RBINS) from Kon Chu Rang National Park, pale morph, terminalia. A–F. Pygofer, anal tube and gonostyli. A. Left lateral view. B. Posterolateral view. C. Caudal view. D. Dorsal view. E. Ventral view. F. Posterodorsal view. G–S. Aedeagus. G. Caudal view. H. Left lateral view. I. Right lateral view. J. Posteroventral view. K. Left laterodorsal view. L. Right laterodorsal view. M. Right posterolateral view. N. Left lateroventral view. O. Right lateroventral view. P. Left posterolateral view. Q. Dorsal view. R. Posterodorsal view. S. Ventral view. Abbreviations: see Material and methods.