Stigmus rugidensus Li & Ma, 2024

Li, Jinghong, Li, Qiang & Ma, Li, 2024, Five new species of the genus Stigmus Panzer (Hymenoptera, Crabronidae) from China, with a key to all Chinese species, ZooKeys 1204, pp. 313-336 : 313-336

Stigmus rugidensus Li & Ma sp. nov.

Figs 4 A – M , 7 E, F

Type material.

Holotype: China • ♀; Yunnan, Kunming City, Yunnan Agricultural University ; 25 ° 7 ′ N, 102 ° 44 ′ E; 12. VI. 2023; 1910 m elev.; coll. Jinghong Li; sweep net ( YNAU) . Paratypes: China • 1 ♂; Yunnan, Kunming City, Shimudi ecological park ; 25 ° 5 ′ N, 102 ° 50 ′ E; 22. V. 2023; 2210 m elev.; coll. Zhizhi Liu; sweep net ( YNAU) .

Diagnosis.

Differs from S. japonicus by hindwing media diverging before cu-a; lateral surface of propodeum smooth and shiny anteriorly and medially, and with sparse, oblique, longitudinal rugae posteriorly; pronotal lobe black; mesopleuron with sparse, midsize punctures, episcrobal area finely coriaceous. Stigmus japonicus has the following characters: hindwing media diverging beyond cu-a; lateral surface of propodeum with dense, slender or sturdy, oblique longitudinal rugae anteriorly and medially, and irregular reticulation posteriorly; pronotal lobe ivory; mesopleuron impunctate, episcrobal area with contiguous, longitudinal rugae.

Description.

Female. Measurements. ♀, BL: 5 mm; HW: HLD: HLF = 75: 57: 57; HW: EWd: EW: TW: EL = 75: 18: 22: 28: 52; POD: OOD: OCD = 9: 13: 17; length of scape: length of pedicel: length of flagellomere I: width of flagellomere I: length of flagellomere II: width of flagellomere II = 24: 10: 10: 6: 10: 5; PL: PW: LTI: WTI: HFL: HTL = 38: 10: 40: 40: 41: 40. ♂, BL: 3.8 mm; HW: HLD: HLF = 70: 45: 47: 55; HW: EWd: EW: TW: EL = 70: 22: 22: 20: 46; POD: OOD: OCD = 8: 12: 14; length of scape: length of pedicel: length of flagellomere I: width of flagellomere I: length of flagellomere II: width of flagellomere II = 17: 10: 5: 5: 10: 5; PL: PW: LTI: WTI: HFL: HTL = 35: 10: 34: 25: 40: 49.

Color pattern. Body black; mandible brown except dark brown apically; labrum dark brown; palpi yellowish; scape, pedicel, tegula and forewing veins brown; flagellomeres I – VII brown to dark brown; pronotal lobe black; fore leg: coxa apically, base and apex of femur, tibia largely, tarsi fulvous, remainder brown to dark brown; mid leg: fulvous except middle of trochanter and tibia dark brown; hind leg: trochanter and tibia largely dark brown, remainder fulvous; gaster dark brown apically; clypeal margin and mandible with sparse golden setae.

Head. Mandible tridentate apically, median tooth large. Labrum pentagonal, and with two distinct triangular teeth apically (Fig. 4 A ). Clypeus shiny, slightly convex, and with sparse, midsize punctures; free margin of clypeus slightly produced and with two distinct, cornuted teeth medially, slightly reflected, distinctly emarginated in middle (Fig. 4 A ). Scapal hollow coriaceous, somewhat shallow, and clearly defined, provided with one vestigial minute tubercle medially, not spined (Fig. 4 A ). Frontal furrow very fine and weakly impressed, inconspicuously; median and upper frons shiny, with sparse, midsize punctures mixed with several large punctures, gently convex (Fig. 4 A ). Ocellar triangle area flat, shiny, impunctate, area near eyes with dense, short, impressed lines, opaque area smaller than hind ocellus (Fig. 4 B ). Vertex shiny, with sparse, large punctures, and with longitudinal line weakly impressed medially (Fig. 4 B ). Gena shiny, with sparse, midsize to large punctures dorsally; ventral gena shiny, smooth and impunctate. Head from above with temples rarely convergent posteriorly, subquadrate (Fig. 4 B ). Occipital carina incomplete, not ending to midventral line, suddenly ended at posterior ridge of stomal hollow, dorsal area narrowed, coarsely crenulate, ventral area slightly broadened, distinctly crenate. Inner and outer orbital furrows lacking (Fig. 4 A ).

Mesosoma. Anterior area of pronotal collar with strong, transverse carina, and with incomplete lateral rugae, only distinct in posterior area, without antero-lateral corner (Fig. 4 C ). Scutum shiny, with sparse, large punctures; admedian line distinctly impressed, extending to 2 / 5 of scutum length; notaulus deeply grooved and crenulate, also reaching 2 / 5 of scutum length; parapsidal line distinctly impressed (Fig. 4 C ). Scutellum shiny, with sparse, midsize to large punctures, and without longitudinal line (Fig. 4 C ). Metanotum slightly matt, finely rugulose (Fig. 4 C ). Mesopleuron shiny, with sparse, midsize punctures, posterior area smooth, without rugae, episcrobal area finely coriaceous; scrobal suture, omaulus and hypersternaulus broadened, distinctly crenate, scrobal suture complete (Fig. 4 D ). Propodeal enclosure U-shaped medially, and with a longitudinal median rugae and sparse, irregular, transverse rugae, with dense, disorganized, slender rugae laterally; posterior surface of propodeum with sparse, irregular rugae, median groove inconspicuous (Fig. 4 E ); lateral surface of propodeum moderately matt, smooth anteriorly and medially, with sparse, oblique longitudinal rugae posteriorly (Fig. 4 D ).

Legs. Outer surface of hind tibia with three long, slender, fulvous to dark brown spines.

Wings. Forewing venation typical for genus Stigmus , hindwing media diverging before cu-a.

Metasoma. Dorsal surface of petiole subquadrate, moderately convex and widened toward apex slightly, and with two sturdy oblique, longitudinal carinae forming V-shaped medially, area between carina with dense, irregular, transverse rugae, median and posterior areas with several sturdy, lateral rugae on each side (Fig. 4 F ); lateral surface of petiole with two sturdy, longitudinal rugae (Fig. 7 E ); ventral surface of petiole with a few sturdy, longitudinal rugae posteriorly. Gastral terga shiny, with sparse, midsize punctures, gastral sterna shiny, sterna II – VII with sparse, fine punctures; pygidial area moderately matt, broadly triangular, and with several, midsize punctures basally (Fig. 4 G ).

Male. Same as female, except: mandible fulvous except reddish brown apically; scape and pedicel fulvous; flagellomeres I – III dark brown; fore leg: inner margin of tibia fulvous, middle of femur dark brown; mid leg: trochanter brown, apex of femur and outer margin of tibia dark brown; hind leg: femur, tibia largely black; setae on clypeus dense, silvery, long (Fig. 4 H ); mandible bidentate apically; clypeus with dense, tiny punctures; free margin of clypeus slightly produced and nearly truncate medially, with shallow emargination, slightly reflected apically (Fig. 4 H ); vertex shiny, impunctate, without longitudinal line medially (Fig. 4 I ); head from above with temples somewhat roundly convergent posteriorly (Fig. 4 I ); flagellomeres without tyloids, setae normal (Fig. 4 I ); lateral surface of propodeum with irregular reticulation posteriorly (Fig. 7 F ); gastral sterna moderately matt, impunctate.

Distribution.

China (Yunnan).

Etymology.

The name, rugidensus, is derived from the Latin rug - (= rugae) and the Latin word densus (= dense), referring to the propodeal enclosure with dense, disorganized, slender rugae on each side.

Figures

Figure 4. Stigmus rugidensus Li & Ma, sp. nov. (A – G female H – M male) A, H head, frontal view B, I head, dorsal view C collar, scutum, scutellum and metanotum, dorsal view D thorax, lateral view E propodeum, dorsal view F petiole, dorsal view G pygidial plate, dorsal view J gastral tergum VIII, ventral view K male genitalia, dorsal view L male genitalia, ventral view M male genitalia, lateral view. Scale bars: 1 mm (A – I); 0.1 mm (J – M).

Figure 7. A, B Stigmus carinannulatus Li & Ma, sp. nov. (A female B male) C, D Stigmus clypeglabratus Li & Ma, sp. nov. (C female, D male) E, F Stigmus rugidensus Li & Ma, sp. nov. (E female F male) A – F lateral view. Scale bars: 1 mm.