Taxonomy of Micronectidae (Heteroptera: Nepomorpha) from Vietnam, with descriptions of 11 new species Author Ha, Tuyet Ngan 568A022B-D36D-4147-8B0D-FB35B2A4D197 Faculty of Biology, VNU University of Science, Vietnam National University, Hanoi, 334 Nguyen Trai, Thanh Xuan, Hanoi, Vietnam. hatuyetngan95@gmail.com Author Tran, Anh Duc 3CB36F17-D917-4600-B888-C33B1C04259F Faculty of Biology, VNU University of Science, Vietnam National University, Hanoi, 334 Nguyen Trai, Thanh Xuan, Hanoi, Vietnam. tran.anhduc@hus.edu.vn text European Journal of Taxonomy 2021 2021-06-24 756 1 82 http://dx.doi.org/10.5852/ejt.2021.756.1407 journal article 5963 10.5852/ejt.2021.756.1407 73c0dde0-1a03-4fe2-8d13-05cd614ff3b1 2118-9773 5033010 4A60FB62-20D7-4DC9-A4EA-BCE633730111 Micronecta ( Micronecta ) pingae sp. nov. urn:lsid:zoobank.org:act: 1B2C7138-D9CD-4B1C-B894-C256CCA5B05A Figs 13I–J , 19 Diagnosis Body length 2.1–2.6. Pronotum longer than median head length. With dark and pale colour forms ( Fig. 13I–J ). Males: fore femur with two spines on proximal third ventrally, one large spine on middle third, one longer spine in distal third dorsally, one pair of spines distally, and one long seta dorsodistally; fore tibia with a pair of long spines on distal third ventrally; palar claw moderately widened distally, apex rounded ( Fig. 19A ). Median lobe of sternite VII with three or four long setae and a narrowly rounded apex ( Fig. 19C ). Free lobe short, strongly widened distally, posterior margin convex medianly and both corners broadly notched, with a row of uniformly short, dark coloured setae restricted to lateral notch ( Fig. 19D ). Left paramere: shaft relatively short and broad, with a pre-apical ridge running to lateral margin, forming a large triangular projection on lateral margin; lateral margin notched on proximal part; mesial margin sinuate distally; apex truncate; basal lobe tongue-shaped, directed towards paramere’s apex ( Fig. 19F ). Right paramere: shaft broad, abruptly constricted and bent at middle part, mesial margin of proximal part convex, apical part strongly wavy and lobate, apex narrowly rounded; pars stridens processus with ca 30 ridges ( Fig. 19E ). Etymology This species is dedicated to Dr Chen Ping-ping, for her significant contributions to the taxonomy and our knowledge of Micronectidae . Material examined Holotype VIETNAM • ♂ ; Nghe An Prov. , Ky Son , Nat’ road 7 , Ta Ca commune, Loi stream; 16 Apr. 2013 ; A.D. Tran et al. leg.; TAD1301 ; ZVNU . Paratypes VIETNAM – Nghe An Prov. • 10 ♂♂ , 14 ♀♀ ; same locality data as for holotype; ZVNU • 2 ♂♂ , 3 ♀♀ ; same locality data as for holotype; NHMW • 5 ♂♂ ; Con Cuong , Lien Huong Village , Khe Thoi stream; 21 Dec. 2012 ; Q.H. Ngo leg.; NQH1209 ; ZVNU • 4 ♂♂ , 3 ♀♀ ; Con Cuong , Tung Huong Village , Khe Thoi stream; 21 Dec. 2012 ; Q.H. Ngo leg.; NQH1210 ; ZRC • 1 ♀ ; Pu Mat N.P. , Khe Kem waterfall and stream , site #2, ca 300 m downstream from waterfall ; A.D. Tran et al. leg.; 18 Apr. 2013 ; TAD1311 ; ZVNU . – Cao Bang Prov. • 1 ♂ , 2 ♀♀ ; Bao Lac , Hung Dao commune, Nhi Ao River , near Nam Xui bridge ; 20 Dec. 2013 ; A.D. Tran et al. leg.; TAD1380 ; ZVNU . Fig. 19. Morphological features of Micronecta pingae sp. nov. , ♂, paratype (ZVNU). A . Fore leg. B . Prestrigilar flap. C . Median lobe of sternite VII. D . Free lobe. E . Right paramere. F . Left paramere. Description COLOUR ( Fig. 13I–J ). With variations in colour of dorsum and pattern of hemelytra (a dark form and a pale form). Dark form (specimens from site TAD1380, Cao Bang Prov. and TAD1301, Nghe An Prov. ) with dorsum generally light brown ( Fig. 13I ): frons and vertex brownish yellow to brown; eyes reddish brown. Pronotum pale yellowish brown. Hemelytron with minute red dots scattered especially on orangish band along anterior margin of clavus, and on boundary between corium and embolium. Corium with three brown marks in middle part, usually fused into one irregular-shaped mark. Right membrane with similar colour and texture to corium, more translucent apically. Left membrane translucent and brown. Venter of thorax and abdomen pale yellow to yellowish brown, and legs very light pale yellow or nearly whitish. Pale form (specimens at site TAD1301, Nghe An Prov. ) ( Fig. 13J ): frons, vertex, and pronotum pale yellowish. Hemelytron with indistinct marks, more like scattered small orangish dots. Membrane with similar colour and texture to corium, more translucent apically. Venter of thorax and abdomen pale yellow, and legs very light pale yellow or nearly whitish. Structural characteristics MACROPTEROUS MALES. Body length 2.19–2.63 ( holotype : 2.38), width 1.0–1.25 ( holotype : 1.23). Head width 0.84–0.87 ( holotype : 0.85). Pronotum 2.75 times as wide as long (0.99: 0.36). Pronotum wider than head. Synthlipsis about 1.6 times as wide as posterior width of an eye (0.41: 0.26). Lengths of leg segments: fore leg: femur 0.30, tibia 0.18, pala 0.20; middle leg: femur 0.77, tibia 0.34, tarsus 0.43, claw 0.25; hind leg: femur 0.49, tibia 0.41, tarsus I 0.41, tarsus II 0.22, claw 0.05. Prestrigilar flap on segment V with prolonged apex ( Fig. 19B ). Strigil present. Median lobe of sternite VII, free lobe, and parameres as in diagnosis. MACROPTEROUS FEMALES. Body length 2.13–2.5, width 1.0–1.28. Head width 0.81–0.85. Pronotum 2.5 times as wide as long (0.90:0.36). Pronotum wider than head. Synthlipsis 1.6 times as wide as posterior width of an eye (0.40: 0.25). Lengths of leg segments: fore leg: femur 0.27, tibiotarsus 0.29; middle leg: femur 0.72, tibia 0.29, tarsus 0.38, claw 0.2; hind leg: femur 0.5, tibia 0.36, tarsus I 0.33, tarsus II 0.16, claw 0.05. Distribution Vietnam : Cao Bang , Nghe An . Remarks Three new species, M. undulata sp. nov. , M. nieseri sp. nov. , and M. pingae sp. nov. , are apparently related to each other and to M. janssoni Nieser, Chen & Yang, 2005 from Yunnan ( China ) by having the left paramere with transverse ridge(s) or grooves on its shaft, a strongly modified apical part of the right paramere, and by the outline of the palar claw. Among these four species, M. undulata sp. nov. is most similar to M. janssoni in the general outline of the prestrigilar flap on segment V, the shape of the median lobe of sternite VII, the broad truncate apex of the left paramere, and the shape of the basal lobe of the left paramere. The characteristics which separate these two species include the structure of the free lobe, the ridges on the left paramere, and the shape of the apical part of the right paramere. In M. undulata sp. nov. , the free lobe is wavy distally, and without long setae, while in M. janssoni , it is only slightly sinuate at the apical margin and with long setae on the lateral angle. The left paramere of M. undulata sp. nov. has two transverse ridges on its shaft, one near the base, and one near the apex, while that of M. janssoni has one transverse ridge near the base of shaft and three less distinct grooves on the distal third of the shaft. The apical part of the right paramere is also differently modified in these two species (compare Fig. 17E with Nieser et al. 2005 : fig. 16). In a parallel manner, M. nieseri sp. nov. is most similar to M. pingae sp. nov. in the general outline of the prestrigilar flap on segment V, the shape of the basal lobe of the left paramere, the notch on the lateral margin near the base of the left paramere shaft, and the sinuate mesial margin of the left paramere. They can easily be separated from each other by the following characteristics. In M. nieseri sp. nov. , the median lobe of sternite VII has an angular apex; the free lobe has a broadly notched lateral corner; and the left paramere has two transverse ridges, one near the basal notch and one near to the tounge-like apex. In M. pingae sp. nov. , the median lobe of sternite VII is narrowly rounded; the free lobe has both lateral and mesial corners broadly notched; and the left paramere has only one transverse ridge pre-apically which runs into a triangular projection and has a truncate apex. The apical part of the right paramere of M. nieseri sp. nov. and M. pingae sp. nov. are both strongly modified, but differently, with that of M. nieseri sp. nov. being more elongate, and that of M. pingae sp. nov. , by contrast, being shorter and broader, with a more acuminate tip. Both M. nieseri sp. nov. and M. pingae sp. nov. have various colour forms, with both having a paler form in which the hemelytra generally are pale yellow and without distinct markings.