Polistes (Polistella) reliciniclypeus Nguyen, Kojima & Saito

Nguyen, Lien Thi Phuong, Kojima, Jun-Ichi & Saito, Fuki, 2011, Polistes (Polistella) wasps (Hymenoptera: Vespidae: Polistinae) from mountainous areas of northern Vietnam, with description of five new species, Zootaxa 3060, pp. 1-30 : 9-14

Polistes (Polistella) reliciniclypeus Nguyen, Kojima & Saito , sp. nov.

( Figs 27–41 , 87 )

Type material. HOLOTYPE: Ƥ (deposited in the IUNH, on long-term loan from the IEBR), labeled “ VIETNAM, Binh Lu, Phong Tho, Lai Chau, 22°21'N 103°43.5'E, alt. 1600 m, Nest#: VN-P- 2006-13, L.T.P. Nguyen, F. Saito & J. Kojima, 22.viii.2006 ”. PARATYPES ( IUNH and AMNH, on long-term loan from the IEBR): VIETNAM: Lai Chau: Binh Lu, Phong Tho, 22°21'N 103°43.5'E, alt. 1600 m, LN, FS & JK, 22. VIII.2006 [15 3, Nest# VN-P- 2006-10; 3 3, 3 Ƥ, Nest# VN-P- 2006-11; 3 Ƥ, Nest# VN-P- 2006-12]; 15 3, 11 Ƥ, same data as holotype; Lao Cai: 2 3, 3 Ƥ, Sa Pa (City, NP office), 22°20'N 103°50'E, alt. 1600 m, Nest# VN-P- 2006-4, 21.VIII.2006, LN, FS & JK; 5 Ƥ, Xin Chai, Sa Pa, alt. 1350 m, 6.VII.2009, HP; 4 Ƥ, Cat Cat, Sa Pa, alt. 1450 m, 7.VII.2009, HP; 2 3, Ta Pin, Sa Pa, alt. 1600 m, 20.VIII.2006, LN, FS & JK; 1 Ƥ, Ban Khoang, Sa Pa, alt. 1800 m, 20.VIII.2006, LN, FS & JK; 1 3, 3 Ƥ, Sa Pa NP (Silver Waterfall), 22°21.5'N 103°46.5'E, alt. 2000 m, 21.VIII.2006, LN, FS & JK; 3 Ƥ, Xeomity, Sa Pa, alt. 1700 m, 9.VII.2009, HP; 1 3, Sa Pa town, alt. 1600 m, 8.VII.2009, HP, 1 3, Sa Pa, alt. 1500–2000 m, 17-18.V. 2003, ISD-c; 6 Ƥ, Sa Pa, alt. 1600 m, Nest# Sapa-P-01, 5.VII.2009, HP; 4 Ƥ, Ban Pho, Bac Ha, Nest# 2008-LC-P-02, 25.VI.2008, LN & HP; 2 Ƥ, Nam Lung, Bac Ha, Nest# 2008-LC-P-03, 26.VI.2008, LN & HP; Dien Bien: 2 Ƥ, Ban Bua, Muong Fang, alt. 1000 m, 14.VI.2001, ISD-c; 1 3, Tuan Giao, alt. 1168 m, 25.VI.2009, LN, HP & JK; 1 3, Co Ma, Thuan Chau, Son La, alt. 1400 m, 4.V.2009, HP; Hoa Binh: 13 Ƥ, Pa Co, Mai Chau, 20°44.5'N 104°53.5'E, alt. 1450 m, Nest # VN-P- 2006-17, 27.VIII.2006, LN, FS & JK; 2 3, 6 Ƥ, Pa Co, Mai Chau, alt. 1000 m, 23.VIII.2006, LN & JK; Pa Co, Mai Chau [1 Ƥ, alt. 900–1000 m, 27.VI.2001, ISD-c; 1 Ƥ, alt. 1100 m, 20.V.2002, V. T. Hoang; 5 Ƥ, alt. 1400 m, Nest# 2008-HB-P-03, 11.VI.2008, LN & HP; 1 3, 2 Ƥ, Pa Co, Mai Chau, alt. 1000 m, 23.VIII.2005, LN & J K.

Diagnosis. This species can be distinguished from all other known species of subgenus Polistella by the following combination of characters: female clypeus convex, produced ventrally into blunt angle, in lateral view prominently swollen anteriorly in dorsal one-third; male clypeus bent backward apically; metasomal tergum 1 short and thick, about 0.9 × as long as its apical width, in lateral view abruptly swollen dorsally at base, with corner between anterior and dorsal faces bluntly angled; metasomal sternum 2 in lateral view strongly swollen ventrally in anterior half to two thirds, then ventral margin bluntly angled into straight line parallel to ventral margin of the tergum.

Description. FEMALE. Body length 10.5–11.5 mm (holotype: about 11 mm); fore wing length 11–12 mm (holotype: about 11 mm).

Head in frontal view about 1.2 × as wide as high ( Fig. 27 ); in dorsal view weakly swollen laterally just behind eyes, then narrowed posteriorly, with posterior margin shallowly and broadly emarginate ( Fig. 28 ). Vertex slightly raised in area among ocelli, slightly slope down behind posterior ocelli towards occpital carina; POD:OOD = about 1:1.9; POD about 1.5 × Od. Gena in lateral view about 0.8 × as wide as eye ( Fig. 29 ); occipital carina fine, evanescent in ventral one third of gena. Inner eye margins weakly convergent ventrally, in frontal view about 1.2 × further apart from each other at vertex than at clypeus ( Fig. 27 ). Antennal sockets closer to inner eye margin than to each other; anterior tentorial pit slightly further from antennal socket than from inner eye margin; interantennal space weakly raised. Clypeus in frontal view as wide as high, produced ventrally into blunt angle; in lateral view convex, prominently swollen anteriorly in upper one third ( Fig. 29 ); lateral margin of clypeus lying along inner eye margin about as long as diameter of antennal socket and shorter than length of malar space. Antenna ( Fig. 30 ): scape more than 3 × as long as its maximum width; flagellomere 1 slightly less than 3 × as long as its maximum width, longer than length of flagellomeres 2 and 3 combined; flagellomere 2 as long as wide; terminal flagellomere bulletshaped, as long as its basal width.

Pronotal carina sharply raised, produced dorsally into thin lamella in dorsal part, slightly sinuate backward on lateral sides, reaching ventral corner of pronotum. Mesoscutum weakly convex ( Fig. 31 ), about as long as wide between tegulae; anterior margin broadly rounded. Scutellum strongly convex except nearly flat median part. Metanotum weakly convex, strongly depressed along anterior margin. Propodeum short; posterior face widely (about half the maximum width of propodeum) and shallowly excavated medially, more or less smoothly passing into lateral faces; propodeal orifice elongate, about 1.8 × as long as wide (measured at widest part), somewhat narrowed in dorsal half. Jugal lobe of hind wing rounded ( Fig. 32 ).

Metasomal tergum 1 short and thick, about 0.9 × as long as its apical width, in lateral view abruptly swollen dorsally just behind basal slit for reception of propodeal suspensory ligament; corner between anterior and dorsal faces bluntly angled ( Fig. 33 ). Sternum 2 in lateral view strongly swollen ventrally in anterior half, then ventral margin bluntly angled into nearly straight line parallel to ventral margin of the tergum.

Clypeus with scattered large punctures, each bearing sharply pointed golden bristle. Mandible with several deep punctures. Frons densely covered with coarse punctures. Vertex and gena with sparse punctures less coarse than those on frons; punctures around ocelli sparse strong; ventral one third of gena with coarse punctures. Pronotum with dense coarse flat-bottomed punctures; spaces between punctures very narrow, slightly raised to form reticulation. Mesocutum densely with coarse flat-bottomed punctures; punctures on scutellum and metanotum dense coarse but smaller than those on mesoscutum. Mesepisternum with dense coarse well-defined punctures in posterodorsal part (punctures in dorsal margin similar to those on pronotum), barely punctured in anteroventral part; border between posterodorsal and anteroventral parts distinct. Dorsal metapleuron with striae; ventral metapleuron with sparse strong punctures. Propodeum with strong transverse striae; lateral face with sparse ill-defined punctures. Metasomal segements densely covered with minute punctures in addition to scattered small punctures (ill-defined on terga; more or less well-defined on sterna).

Color. Black; following parts yellow to orange-yellow: clypeus except black margins, narrow band along inner eye margin extending from bottom of frons to middle of eye emargination, narrow short band along eye margin in dorsal part of gena, narrow band along pronotal carina with branches extending along posterodorsal margin of pronotum, anterior transverse band on scutellum (often most of scutellar disc, sometimes reduced to paired anterolateral spots), paired anterolateral spots on metanotum (sometimes united into narrow to wide anterior band), spot on propodeal valvula, narrow subapical band on tergum 1 (often narrowly interrupted medially), wide apical band with irregular anterior margin on tergum 6; following parts reddish brown: mandible except black basal margin and teeth, antennal scape beneath, pedicel, basal part of flagellomere 1, apical flagellomeres beneath, pronotum ventrolaterally, tegulae, ill-defined wide bands on tergum 1 (in front of yellow band), narrow apical bands on terga 2, 3 and 5 and sterna 2–5, entire visible part of metasomal segment 6. Legs black, dorsal surface of femora and ventral surface of tibiae largely reddish brown. Wings yellowish-brown, weakly infuscate, slightly more strongly infuscate along anterior margin of fore wing; veins dark brown.

MALE. Body length 9.0 mm– 9.5 mm; forewing length 9.5–10.5 mm.

Structure as in female, but differing from the latter as follows: head proportionally smaller, transverse, about 1.4 × as wide as high in frontal view ( Fig. 34 ); eye strongly swollen laterally; inner eye margins strongly convergent, about 1.5 × further apart from each other at vertex than at clypeus; gena narrow, in lateral view about 0.4 × as wide as eye ( Fig. 35 ), with weakly raised blunt ridge running along posterior margin of eye; clypeus in frontal view about 1.1 × as wide as high ( Fig. 34 ), only slightly produced ventrally, evenly and very weakly rounded apically, in lateral view weakly convex dorsally, bent backward ventrally ( Fig. 35 ). Antenna slenderer than in female ( Fig. 36 ); scape short, about 2.8 × as long as its maximum width; flagellomere 1 as long as length of flagellomeres 2 and 3 combined; flagellomeres 2 and 3 each longer than wide; terminal flagellomere elongate, slightly curved, about 2 × as long as its basal width. Metasomal sternum 7 depressed medially ( Fig. 37 ), without tubercle ( Fig. 38 ).

Body surface sculpture as in female, but clypeus without large punctures and densely covered with long golden hairs.

Color. Similar to female, but reddish-brown markings on head and mesosoma reduced, while more extensively marked with yellow as follows: clypeus entirely, mandible except for small basal black spot, ventral half of frons except for ill-defined black band connecting anterior tentorial pit and antennal socket and interantennal black spot, narrow long band on gena along posterodorsal margin of eye, antennal scape beneath, disc of scutellum (sometimes reduced into wide anterior band), paired anterolateral spots (sometimes narrow transverse band) on metanotum, spot on propodeal valvula, ventral face of fore coxa and spot on mid-coxa; antennal flagellum reddish-brown to dark yellow beneath.

Genitalia. Generally similar to that of Polistes dawnae . Lamina volsellaris desclerotized and fused with cuspis. Digitus in inner aspect of paramere ( Fig. 39 ) slightly more than 3.5 × as long as wide (measured at widest part), distinctly swollen near base, gradually narrowed apically to mid-length, then slightly swollen towards the rounded apex. Aedeagus ( Figs 40, 41 ): penis valves slightly longer than basal apodeme, in ventral view narrowest near midlength, distally club-shaped, weakly swollen proximally from mid-length, strongly swollen and produced proximolaterally in about proximal one fourth and distinctly produced laterally near proximal margins, in lateral view slightly thickened in proximal one fourth and with dorsal margin weakly and smoothly sinuate, with proximoventral corner produced into abtuse angle ( Fig. 41 ); ventral margins of penis valves finely serrated along entire length.

Nest. The following nine nests were examined: Nest# VN-P-2006-4, Sa Pa, Lao Cai, alt. 1600 m, 21.VIII.2006, LN, FS & JK; Nest# 2009-Sapa-P-01, Sa Pa, Lao Cai, alt. 1600 m, 5.VII.2009, HP; Nest# VN-P- 2006-10 to -13, Phong Tho, Lai Chau, alt. 1600 m, 22.VIII.2006, LN, FS & JK; Nest# 2008-LC-P-02 & 0 3, Bac Ha, Lao Cai, 25 & 26.VI.2008, LN & HP; Nest# 2008-HB-P-03, Mai Chau, Hoa Binh, alt. 1400 m, 11.VI.2008, HP.

Nest VN-P-2006-4 was found under the leaf of a palm about 0.5 m above the ground. Five nests (VN-P- 2006- 10 to 13 and 2009-Sapa-P-01) were found on the cliffs along the Hoang Lien Pass road, and they all were directly attached to rocks 1 to 2 m above the road. The two nests collected in Bac Ha and one in Mai Chau were at the early nest-founding stage and had a comb comprised of only empty shallow cells ( Table 1 ).

Nest structural characters are as follows (for measurements see Table 3 ). Petiole single, terminal, with thin central core of plant fibers, enlarged strictly with adult salivary secretion, black and lustrous; salivary coating extended onto substrate and largely onto back of comb. Comb tough, pliable in texture, dark brownish gray, expanded from Nest coder Petiolate Petiole Cell width at open end Cell width at bottom Cell depth (mm) (N=10)

length thickness (mm) (n=10) (mm) (n=10)

(mm) (mm)

Mean Range Mean Range Mean Range the petiole to become fan-shaped in ventral view; ventral surface convex; dorsal surface deeply concave. Nest cells generally arranged regularly and hexagonal at open end, but partly irregularly arranged, where some cells are pentagonal; outer free margins of peripheral cells rounded; cell expanded towards open end, with width at open end about 1.5 × larger than that at bottom ( Table 3 ); cell wall about 0.03 mm thick. Cocoon caps pale gray, domed, projecting 1 to 2 mm beyond rim of cell.

Remark. Along the Hoang Lien Pass road this species and P. l e p c h a nested on the cliffs. While the nests of P. lepcha , having pale-green cocoon caps, were rather conspicuous to us, it seemed to us that the nests of this new species are well camouflaged. Two nests collected in Bac Ha and one in Mai Chau suggested that this species commonly founds a nest by multiple females.

Etymology. The specific name refers to the male clypeus bent back (relicinus in Latin) ventrally and is treated as a noun in aposition.

Distribution. Known only from northern Vietnam.

Figures

FIGURES 27 – 33. Polistes (Polistella) reliciniclypeus sp. nov., Ƥ. 27 – 29. Head. 27. Frontal view. 28. Dorsal view. 29. Lateral view. 30. Left antenna. 31. Jugal lobe of left hind wing. 32. Mesosoma, lateral view. 33. Metasomal segments 1 and 2, lateral view. Scale 1 mm.

FIGURES 34 – 41. Polistes (Polistella) reliciniclypeus sp. nov., 3. 34 – 35. Head. 34. Frontal view. 35. Lateral view. 36. Left antenna. 37 – 38. Terminal sterna. 37. Ventral view. 38. Apical part, lateral view. 39. Inner aspect of paramere with digitus and volsella. 40 – 41. Aedeagus. 40. Ventral view. 41. Lateral view. Scale 1 mm.

FIGURES 85 – 88. Nests of Polistes species of subgenus Polistella occurring in northern Vietnam. 85. P. dawnae (Nest # 2009 - DB-P- 01). The thick and thin arrows indicate the position of the primary petiole and the subsidiary petioles, respectively. 86. P. l e p c h a (Nest # VN-P- 2006 - 3). 87. P. reliciniclypeus sp. nov. (Nest # VN-P- 2006 - 13). 88. P. gilvus sp. nov. (Nest # 2008 - SL-P- 1).

Tables

TABLE 3. Measuments of nests of Polistes reliciniclypeus sp. nov.

VN-P-2006-4	5.1	1.1 x 1.4	4.0	3.5–4.5	2.8	2.5–3.2	16.3	15.1–17.2
VN-P-2006-10	3.8	1.4 x 1.5	4.1	3.9–4.3	3.1	2.7–3.9	16.7	15.6–17.9
VN-P-2006-11	1.9	1.6 x 2.0	4.7	4.3–5.2	3.0	2.5–3.7	16.4	15.3–17.7
VN-P-2006-12	-	-	3.9	3.7–4.2	2.7	2.2–3.4	17.5	15.9–19.6
VN-P-2006-13	4.4	1.6 x 1.9	4.4	4.0–5.0	2.8	2.4–3.4	17.6	16.2–19.2
2009-Sapa-P-01	5.7	1.2 x 1.8	4.0	3.6–4.4	2.8	2.4–3.3	16.6	16.3–17.0