Sphex jucundus, Doerfel, Thorleif H. & Ohl, Michael, 2015

Doerfel, Thorleif H. & Ohl, Michael, 2015, A revision of the Australian digger wasps in the genus Sphex (Hymenoptera, Sphecidae), ZooKeys 521, pp. 1-104 : 60-62

Taxon classification Animalia Hymenoptera Sphecidae

Sphex jucundus sp. n.

Material examined.

Holotype. ♂, AUSTRALIA:WA: 6 km N of Winning HS, 23°06'S, 114°33'E, 30.03.1971, E. F. Riek (ANIC). Paratypes. [COUNTRY UNKNOWN]:[state unknown]: [no specific locality], 1♀ (ZMB). AUSTRALIA:NSW: Bourke, 1♀, 03.01.1954, K. M. Moore (AMS); Broken Hill, 1♂, 09.03.2001, M. Ohl (ZMB); 10 km N of Broken Hill, 2♀, 3♂, 11.03.2001, M. Ohl (ZMB), 4♀, 10♂, 12.03.2001, M. Ohl (ZMB), 1♀, 1♂, 13.03.2001, M. Ohl (ZMB); NT: Alexandria, Nicholson, 2♂, W. Stalker (BMNH); Port Darwin, 1♀, 01.02.1902 (BMNH), 2♂ (BMNH); QLD: Camooweal, 1♂, 18.05.1972, G. B. & S. R. Monteith (ANIC); 45 km S of Collinsville, 1♀, 16.01.1987, M. S. & B. J. Moulds (AMS); Westwood, 1♀, 25.11.1923, A. N. Burns (ANIC); SA: Adelaide, 1♂ (ZMB); Clements Gap Conservation Park, 33°28.7'S, 138°03.9'E, 2♂, 18.12.2010, V. Ahrens & W. J. Pulawski (CAS); Cocata Conservation Park, 33°17.0'S, 135°19.7'E, 1♂, 03.01.2011, V. Ahrens & W. J. Pulawski (CAS); 55 km ESE of Kimba, on Kimba/Iron Knob road, 1♂, 12.12.1995, M. S. & B. J. Moulds & K. A. Kopestonsky (AMS); Lake Gilles Conservation Park, 1♀, 01.02.1995, L. Packer, M. Schwarz, P. Hurst, Y. Pamula (ZMB); WA: Bullsbrook, 1♂, 13.02.1966, O. W. Richards (BMNH); Bunbury, 2♂, 03.01.1957, A. Snell (AMS), 1♂, 01.01.1961, A. Snell (AMS); Deep Dene, Karridale, 1♂, 19.01.1965, L. M. O’Halloran (ANIC); Kalamunda, 1♀, 09.-28.02.1914, R. E. Turner (BMNH), 1♀, 14.03.-14.04.1914, R. E. Turner (BMNH); 40 km SE Kalbarri, 27°50.9'S, 114°28.5'E, 1♀, 05.11.2008, V. Ahrens & W. J. Pulawski (CAS); Marloo Station, 1♀, 01.01.1935, Gebr. Goerling (ZMB), 1♀, 1♂, 01.02.1935, Gebr. Goerling (ZMB), 1♀, 01.01.1936, A. Goerling (ZMB), 1♀, Dec 34, Gebr. Goerling (ZMB); Meekatharra, 1♂, 18.01.1961, A. Snell (AMS); 55 km S of Newman, 1♀, 1♂, 08.04.1971, E. F. Riek (ANIC); Perth, 1♂, 10.-18.02.1936, R. E. Turner (BMNH); S of Perth, 1♀, 12.01.1905, H. M. Giles (BMNH), Serpentine Falls, Darling Ranges, 1♀, 20.01.1971, G. A. Holloway (AMS); Shire of Shark Bay, Francois Peron National Park, 25.906233°, 113.526010°, 1♀, 12.01.2010, L. Breitkreuz (ZMB); Tuckanarra Hill, 2♂, 16.11.1961, A. Snell (AMS); Urawa Nature Reserve ca 5 km N Mullewa, 28°29.6'S, 115°29.5'E, 1♂, 11.11.2008, V. Ahrens & W. J. Pulawski (CAS)

Diagnosis.

The combination of black legs, a black metasoma, wings hyaline at the base, exclusively silvery-white pubescence on the clypeus and a petiole considerably longer than flagellomere II separates Sphex jucundus from all other species in the Sphex subtruncatus group except Sphex bilobatus . In contrast to Sphex bilobatus which possesses a convex scutellum with a medial impression, females of Sphex jucundus have a flat scutellum without any impressions; while the visible part of metasomal sternum VIII in male Sphex bilobatus is modified into two long lobes that are even visible from above, while sternum VIII of Sphex jucundus is entire.

Description.

Body length 18.7-20.0 mm. Body black, mandible ferruginous basally. Wing membrane completely hyaline, only with slightly fuscous band at apex of forewing. Wing veins light to dark brown. Appressed pubescence and erect setae on clypeus and frons silvery-white. Clypeus with medialglabrous stripe. Pubescence on mesosoma silvery-white, on scutum denser laterally and posteriorly. Tomentum moderately dense on metasomal tergum I, sparse on tergum II.

Female: Free clypeal margin simple, clypeus elevated medially above margin, pubescent near margin. Distance between hind- ocelli almost equal to their shortest distance to compound eyes. Forebasitarsal rake with 12 long spines. Scutellum flat, without impressions. Pubescence on propodeal enclosure mostly concealing sculpture. Length of petiole 1.25 × length of flagellomere II.

Male: Free clypeal margin truncate, concave towards center. Clypeus near margin glabrous. Distance between hind- ocelli 1.25 × their shortest distance to compound eyes. Scutellum convex, with medial impression. Pubescence on propodeal enclosure sparse enough to leave sculpture visible. Length of petiole 1.4 × length of flagellomere II. Several erect silvery setae on metasomal terga V–VII. Silvery pubescence on margin of metasomal sternum VII and on metasomal sternum VIII. Metasomal sternum VIII entire, its lateral margin concave.

Discussion.

In this species, males and females closely resemble each other, except for commonly sexually dimorphic characters such as the scutellum. Due to this dimorphism, however, the females are easier to define as a new species than the males. At most, only four other females in the Sphex subtruncatus group are known to have a flat scutellum. Two of those are distinguished in having golden pubescence on the propodeal enclosure, and the petiole of the other two is considerably shorter than flagellomere II.

One character was found in which males and females of Sphex jucundus differ from each other and which is usually not a sexually dimorphic feature among Australian Sphex , the density of the pubescence on the propodeal enclosure. However, this argument alone would not be sufficient to demonstrate that they belong to different species. The identical coloration of the wings in males and females as well as the conspicuously dense tomentum both have on their metasomal tergum I are only a few of their shared features. Finally, a great number of males and females come from the same or from nearby localities, which is another indication that both form one species (Fig. 26).

Etymology.

Jucundus is a Latin adjective, meaning “pleasant” or “merry”. The name was apparently chosen by J. van der Vecht when he so labeled individuals of this species in the 1970s, but without describing it. The name was adopted to credit J. van der Vecht.