Micronecta (Micronecta) clavata Tran 2021, sp. nov.
Creators: name: Ha, Tuyet Ngan
name: Tran, Anh Duc
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Corixidae
Micronecta
Micronecta clavata

description: Micronecta (Micronecta) clavata sp. nov.
urn:lsid:zoobank.org:act: B4B1E7DD-177F-498A-9A98-80185920F66D
Figs 13C–D, 15
Diagnosis
Body length 1.4–1.7. Pronotum longer than median head length. Dorsum colour variable. Hemelytron with irregular-shaped light brown marks, sometimes indistinct (Fig. 13C–D).
Males: fore femur with two spines on proximal third ventrally, one spine on distal third dorsally, one pair of spines distally, and one long seta dorsodistally; fore tibia without spine; palar claw moderately widened distally, apex rounded (Fig. 15A). Median lobe of sternite VII with angular apex and three or four long setae (Fig. 15C). Free lobe sub-rectangular, mesial angle rounded, lateral angle nearly square, with ca 10 long setae, posterior margin straight (Fig. 15D). Left paramere: shaft broad, flat, with a triangular projection in the middle of lateral margin, distal part tapering towards rounded apex; basal lobe large, sub-rectangular (Fig. 15F). Right paramere: shaft slender and parallel sided proximally, distal fourth curved, club-shaped with a truncate tip; pars stridens processus with about 20 ridges (Fig. 15E).
Etymology
The species epithet refers to the club-shaped apex of the right paramere.
Material examined
Holotype
VIETNAM • ♂; Cao Bang Prov., Ha Quang, road 203, Truong Ha commune, stream near Kim Dong tomb; 17 Dec. 2013; A.D. Tran et al. leg.; TAD1371; ZVNU.
Paratypes
VIETNAM – Cao Bang Prov. • 4 ♂♂, 2 ♀♀; same locality data as for holotype; ZVNU. – Phu Tho Prov. • 2 ♀♀; Xuan Son N.P., Chieng stream, near ranger station; 21°06.072′ N, 104°59.433′ E; 27 Aug. 2014; T.S. Nguyen leg.; TS1408; ZVNU • 1 ♂; Xuan Son N.P., Ha Bang stream, near its confluence with Xoan stream; 21°5.318′ N, 104°58.87′ E; 6 May 2016; T.S. Nguyen leg.; TS1606ĐT; ZVNU • 3 ♂♂, 1 ♀; Xuan Son N.P., Ha Bang stream, Ha Bang village area; 21°04.343′ N, 104°59.182′ E; 7 May 2016; T.S. Nguyen leg.; TS1610; ZRC • 1 ♂; Xuan Son N.P., Xoan stream, Xoan village area; 21°05.270′ N, 104°57.591′ E; 7 May 2016; T.S. Nguyen leg.; TS1609; ZVNU • 1 ♂; Xuan Son N.P., Kim Thuong, Xoan stream; 28 Aug. 2013; A.D. Tran et al. leg.; TAD1343; ZVNU • 1 ♂; Xuan Son N.P., Ban Coi, Coi stream, site 1, water from underground; 29 Aug. 2013; A.D. Tran et al. leg.; TAD1349; ZVNU • 4 ♂♂, 5 ♀♀; Xuan Son N.P., Coi stream, site 3, in front of cave; 21°01.190′ N, 104°56.624′ E; 24 May 2015; T.S. Nguyen leg.; TS1519; ZVNU • 1 ♀; Xuan Son N.P., Coi stream, site 3, in front of cave; 21°01.190′ N, 104°56.624′ E; 27 Aug. 2015; T.S. Nguyen leg.; TS8519 ZVNU • 1 ♂; Xuan Son N.P., Than stream, site 2; 21°11.257′ N, 104°52.382′ E; 24 May 2015; T.S. Nguyen leg.; TS1515; ZVNU. – Hanoi • 2 ♂♂, 1 ♀; Ba Vi N.P., Khoang Xanh, Tien stream; 95 m a.s.l.; 17 Dec. 2011; Q.H. Ngo and A.D. Tran leg.; TAD1127; NHMW • 7 ♂♂, 12 ♀♀; Ba Vi N.P., Khoang Xanh, Tien stream; 95 m a.s.l.; 27 Apr. 2012; Q.H. Ngo and A.D. Tran leg.; TAD1208; ZVNU. – Ha Tinh Prov. • 1 ♀; Vu Quang N.P., Song Con River; 23 Apr. 2003; A.D. Tran leg.; TAD0302; ZRC.
Description
COLOUR (Fig. 13C–D). With two colour forms, especially colour pattern of hemelytra. Darker form, with distinct dark marks on dorsum (specimens from Phu Tho Prov.): frons and vertex pale yellowish, eyes dark reddish brown. Pronotum light brown. Clavus with a discrete dark brown stripe parallel to suture margin, and a transverse brown mark at anterior margin. Corium with three distinct longitudinal stripes, confluent posteriorly. Membrane translucent and brown. Venter of thorax and abdomen dark brown and legs brownish yellow. Paler form with dorsum generally light yellowish brown (specimens from Cao Bang Prov.): frons and vertex pale, eyes dark reddish brown. Pronotum pale yellowish brown. Hemelytron hyaline light yellowish. Clavus with brown suture margin. Corium with light brown longitudinal stripes indistinct. Membrane transculent, light yellowish. Venter of thorax and abdomen light yellowish orange, legs pale yellow.
Structural characteristics
MACROPTEROUS MALES. Body length 1.53–1.75 (holotype: 1.69), width 0.84–1.02 (holotype: 0.95). Head width 0.59–0.72 (holotype: 0.67). Head slightly wider than pronotum. Pronotum short, about four times as wide as long (0.61: 0.14). Synthlipsis about 1.4 times as wide as posterior width of an eye (0.27: 0.19). Lengths of leg segments: fore leg: femur 0.22, tibia 0.10, pala 0.13; middle leg: femur 0.52, tibia 0.18, tarsus 0.25, claw 0.16; hind leg: femur 0.43, tibia 0.27, tarsus I 0.30, tarsus II 0.12, claw 0.05. Prestrigilar flap on segment V tongue-shaped (Fig. 15B). Strigil present. Median lobe of sternite VII, free lobe, and parameres as in diagnosis.
MACROPTEROUS FEMALES. Body length 1.37–1.81, width 0.72–1.02. Head width 0.59–0.68. Head slightly wider than pronotum. Pronotum about four times as wide as long (0.61: 0.14). Synthlipsis 1.6 times as wide as posterior width of an eye (0.27: 0.17). Lengths of leg segments: fore leg: femur 0.18, tibiotarsus 0.18; middle leg: femur 0.5, tibia 0.18, tarsus 0.25, claw 0.14; hind leg: femur 0.42, tibia 0.27, tarsus I 0.27, tarsus II 0.12, claw 0.04.
Distribution
Northern Vietnam (Cao Bang, Phu Tho).
Remarks
Among species of Micronecta occurring in Vietnam, four species, namely M. ornitheia, M. pocsi, M. tuwanoni, and M. clavata sp. nov., are most similar to each other, in having a triangular projection on the margin of the shaft of the left paramere. This structure is also present in the left paramere of M. erythra. However, the right paramere of M. erythra is evenly curved throughout the length of its shaft, while that of four species above is nearly straight or only curved near the base of the shaft.
The key structure which can help to reliably separate M. ornitheia, M. pocsi, M. tuwanoni, and M. clavata sp. nov. from each other is the apical part of the right paramere. In M. ornitheia, it is widened, with a small tip making it resemble a bird head. In M. pocsi, it is flap-like, with a small notch on the upper margin before apical part. In M. tuwanoni, the shaft of the right paramere is bent at the distal fourth and the apical part is not widened but tapering towards its tip. In M. clavata sp. nov., it is club-shaped and its tip is more truncate, not modified.
The left paramere of these four species also has diagnostic features. In M. ornitheia, the triangular projection is situated near to the base of the shaft, and there is a distinct notch basally to the projection; and the basal lobe is longer than wide, and sub-trapezoid. In M. pocsi, the triangular projection is also nearer to the base of shaft, but there is no notch on the lateral margin; and the basal lobe is sub-triangular. In M. tuwanoni, the triangular projection arises on the proximal third (thus nearer to the base) of the shaft, and the basal lobe is trapezoid. In M. clavata sp. nov., the triangular projection is near to the middle part of the lateral margin of the shaft, and the basal lobe is sub-rectangular.
description: Published as part of Ha, Tuyet Ngan & Tran, Anh Duc, 2021, Taxonomy of Micronectidae (Heteroptera: Nepomorpha) from Vietnam, with descriptions of 11 new species, pp. 1-82 in European Journal of Taxonomy 756 on pages 49-51, DOI: 10.5852/ejt.2021.756.1407, http://zenodo.org/record/5033010