Mongoliana vietnamica, Constant & Pham, 2024

Constant, Jérôme & Pham, Hong Thai, 2024, Sixteen issid planthopper species in one day in Dong Son-Ky Thuong Nature Reserve in North Vietnam: Eight new species, one new genus and additional new records (Hemiptera: Fulgoromorpha: Issidae), European Journal of Taxonomy 919 (1), pp. 1-87 : 42-46

Mongoliana vietnamica sp. nov.

urn:lsid:zoobank.org:act:E826177B-3BDE-4304-A518-A58F965B48BA

Figs 1 , 22–23

Diagnosis

Mongoliana vietnamica sp. nov. can be recognized by

(1) the frons with a row of tubercles along lateral margins ( Fig. 22D );

(2) the frontoclypeal suture marginated dorsally with a narrow black line and a slightly wider pale yellowish line, and ventrally by a pale yellowish line preceding the black clypeus ( Fig. 22B, D );

(3) the tegmina uniformly olivaceous, without marking ( Fig. 22A, C );

(4) the lateroventral processes of the aedeagus elongate, first directed ventrocephalad, then strongly recurved posterodorsad in basal half, and weakly curved posteromesad and showing a helical groove in distal half (lvp – Fig. 23D–E, H );

(5) the rather short gonostyli with squarish apical margin (G – Fig. 23A );

(6) the posterior margin of the anal tube weakly rounded (An – Fig. 23C ).

Differential diagnosis

The closest species are M. chilocorides ( Walker, 1851) , M. lanceolata Che, Wang & Chou, 2003 , M. qiana Chen, Zhang & Chang, 2014 and M. recurrens ( Butler, 1875) , sharing with M. vietnamica sp. nov. the uniformly coloured tegmina, and, more or less, the pattern of the frons and clypeus ( Chen et al. 2014; Meng et al. 2016; Zhang et al. 2020). However, M. vietnamica can be separated from all the other species by the characters of the male terminalia, especially the shape of the lateroventral processes of the aedeagus, strongly recurved and with helical groove in distal half, the squarish apical margin of the gonostyli in lateral view and the subtriangular, roundly truncate apically, anal tube.

Etymology

The species epithet refers to the country where the new species was found.

Type material

Holotype

VIETNAM • ♂ (dissected – Figs 22–23 ); Quang Ninh Province, Dong Son-Ky Thuong Nature Reserve ; 21°08′29″ N, 107°04′53″ E; 27 Aug. 2022; 550 m a.s.l.; secondary forest; GTI Project; J. Constant, J. Bresseel and L. Semeraro leg.; I.G.: 34.518; RBINS.

Paratypes

VIETNAM • 1 ♂ (dissected); same collection data as for holotype; VNMN.

Description

MEASUREMENTS AND RATIOS. LT: ♂ (n = 2): 4.6–4.8 mm; LT/BB = 1.37; LTg/BTg = 1.75; LW/BW = 1.9; BV/LV = 2.0; LF/BF = 1.1.

HEAD ( Fig. 22A–D ). Vertex twice as broad as long in midline, brown with paler markings along anterior and lateral margins; middle portion of anterior margin straight, lateral portions oblique, posterior margin concave; lateral and posterior margins weakly carinate; disc weakly concave. Side of head yellowish with brown area anterior to antenna. Frons elongate and rugose, brown with more or less developed minute yellowish dots; dark brown narrow band with yellowish tubercles along lateral margins; narrow black line above frontoclypeal suture with wider pale yellowish line above it. Clypeus black with pale yellowish band under frontoclypeal suture and anteclypeus brown, elevated medially. Labium pale yellowish. Scape short, ring-shaped, brown; pedicel slightly elongate, subcylindrical, brown.

THORAX ( Fig. 22A, C–D ). Brown. Pronotum very short with obsolete median carina marked by pale yellowish line, and anterior and posterior margins weakly carinate; posterior margin curved; disc more or less flat with 2 impressed points; row of yellowish tubercles along anterior margin and 2 tubercles along posterior margin; very narrow, laminate, behind eyes; paranotal fields subtriangular, pale yellowish with laterodorsal brown area extending behind antenna. Mesonotum subtriangular with anterior margin concave, rugulose with weakly marked to obsolete median carina and weak impressed point on each side of disc; lateral carinae of disc indistinct, sometimes marked by pale line, like median carina; curved transverse carina along anterior margin; apex of scutellum marked with pale yellowish. Tegulae brown.

TEGMINA ( Fig. 22A, C ). Strongly convex, olivaceous; distinctly longer than broad when taken together in dorsal view; weakly impressed at basocostal angle and with margin of basicostal angle produced anteriorly in a round lobe; smooth with indistinct veins; costal margin broadly rounded in dorsal view and in lateral view; apex narrowly rounded.

HIND WINGS ( Fig. 22E ). Brown, unilobed, with veins darker, slightly shorter than tegmina. Venation reticulate with main longitudinal veins distinct basally (C, ScP+R, MP, CuA); numerous cross-veinlets. Anal area absent. Costal margin strongly sinuate, cubital and distal margins rounded.

LEGS ( Fig. 22A–D ) Moderately elongate and slender, greenish yellow-brown with coxae, large middle portion of pro- and mesofemora, longitudinal markings on mesofemora and spines of metatibiae, black. Posterior tibiae with 2 lateral spines in apical ½ and 6 apical spines. Metatibiotarsal formula: (2) 6 / 8 / 2.

MALE TERMINALIA. Pygofer (Py – Fig. 23A–C ) in lateral view 2.4 times as high as broad and with posterior margin rounded in dorsal ½ and weakly sinuate in ventral ½; ventral margin rounded in lateral view; anterior margin weakly curved in dorsal portion. Gonostyli (G – Fig. 23A–C ) in lateral view rather short and subquadrate with ventral margin weakly rounded and posterior margin at more or less straight angle to ventral one, truncate with upper and lower angles rounded; capitulum well developed, elongate, projecting dorsomesad, with neck rather short and broad, and basal hump; with small tooth on dorsal margin pointing ventromesad, and basolateral laminate process curved lateroventrad, appearing as hook in caudal view. Anal tube (An – Fig. 23A–C ) slightly (1.15 times) longer in midline than wide, moderately curved ventrally in lateral view, dorsoventrally flattened with sides evenly diverging along basal ⅔, then rounded to apicolateral angles; apical margin weakly rounded, with small protruding portion in middle; apicolateral angles slightly curved ventrad. Aedeagus ( Fig. 23D–I ) strongly curved posterodorsally, rather simple, with elongate lateroventral processes (lvp) at about basal 2/5, first directed ventrocephalad, then strongly recurved posterodorsad in basal half, and weakly curved posteromesad and showing a helical groove in distal half; ventral lobe of periandrium (vl) truncate apically with lateral angles rounded, slightly produced; lateral lobes of periandrium (ll) surpassing ventral lobe, rounded and with minute teeth on margin in distal portion; phallus membranous, dilated and curved apically.

Biology

Mongoliana vietnamica sp. nov. was collected in August on lower vegetation and bushes, in moist evergreen tropical forest at about 550 m in altitude ( Fig. 1B ).

Distribution

Vietnam: Quang Ninh Province, Dong Son-Ky Thuong Nature Reserve ( Fig. 1A ).

Figures

Fig. 1. Dong Son-Ky Thuong Nature Reserve. A. Topographic map. B. Sampled habitat.

Fig. 22. Mongoliana vietnamica sp. nov., dissected holotype, ♂ (RBINS). A. Habitus, dorsal view. B. Habitus, ventral view. C. Habitus, lateral view. D. Habitus, perpendicular view of frons. E. Right hind wing.

Fig. 23. Mongoliana vietnamica sp. nov., holotype, ♂ (RBINS), terminalia. A–C. Pygofer, anal tube and gonostyli. A. Lateral view. B. Caudal view. C. Dorsal view. D–I. Aedeagus and connective. D. Left lateral view. E. Right lateral view. F. Caudal view. G. Ventral view. H. Dorsal view. I. Anterodorsal view. Abbreviations: see Material and methods.