Cerceris venusta oceanica Brèthes 1920

Cerceris venusta oceanica Brèthes

Cerceris oceanica Brèthes, 1920, p. 411.

Cerceris insulicola Tsuneki, 1968a, p. 27. NEW SYNONYMY.

Brèthes’ description of this taxon was brought to my attention by Dr. Arnold Menke after this revision had been set in galleys; for some reason it was never cataloged in the Zoological Record. Thus, I have not had an opportunity to ascertain the type depository nor to obtain any information on the holotype. It was described from a single male from Yule Island along the southeast coast of New Guinea, a short distance west of Port Moresby, Papua. Fortunately, the original description is detailed enough so there can be no question as to the identity of oceanica. The presence of four yellow spots on the vertex is diagnostic of the taxon I treat here as venusta oceanica; it is the only Melanesian Cerceris with these distinctive markings.

Tsuneki’s type series of insulicola from Prince of Wales Island at the tip of Cape York Peninsula, Australia, is before me. It is identical with venusta oceanica which has a wide range in New Guinea east of 146°. In describing insulicola from males only, Tsuneki questioned whether it was possibly the opposite sex of venusta. His conjecture was correct except that insulicola represents a discrete subspecies.

FEMALE.—Length, 9–11.5 mm, forewing 7–9.5 mm. Black, the following yellow: mandible except apex, clypeus, broad quadrate mark somewhat narrowed above along inner eye margin and extending from clypeus upward to a point halfway between antennal insertions and anterior ocellus, narrow streak along interantennal lamella ending just before anterior ocellus, antennal scape beneath, an oblique oval spot on each side of vertex, a narrow stripe occasionally reduced to a spot on temple along outer margin ending on top of head so that viewed from above the back of the head has 4 yellow spots, large quadrate spots on pronotal dorsum narrowly separated in middle, tegula except margins, transverse bands on scutellum and postscutellum, small rounded spot on upper part of mesopleuron, propodeum with a pair of large rounded spots principally on dorsal and posterior aspects (enclosure black), a pair of small lateral spots on 1st tergum, a pair of large rounded posterolateral spots on 2nd tergum, occasionally extending on sides almost to anterior margin, an extremely narrow apical band on 3rd tergum, broader apical bands on 4th and 5th terga which narrow gradually toward middle, a small spot on each side of the 6th tergum adjacent to pygidium, coxae beneath at apices, trochanters beneath, fore and mid femora with stripes beneath, and outer surface of fore and mid tibiae and tarsi. The following are ferruginous: scape except beneath, pedicel and first 3 flagellar segments entirely, rest of antenna beneath, tegula on margins, apex of 1st tergum, posterior half of 2nd tergum between the yellow spots, pygidium, 2nd and 6th sterna, broad transverse bands on intervening sterna, and legs except as noted above and except for some small infuscated streaks on hind femur and tibia. Vestiture short, light brown above, silvery on head and thorax beneath, and on sides of latter. Forewing with anterior margin infumated moderately, stigma yellow, and veins testaceous.

Head (Figure 13) dull, broad, its greatest width 1.5 times its height (apex of clypeus to posterior ocelli), inner eye margins distinctly converging above, the interocular distance at posterior ocelli 0.83 times that at intersection of epistomal suture and inner eye margin; inner margin of mandible with 2 blunt, well-separated teeth on middle third; apical margin of median lobe of clypeus broadly and shallowly emarginate with a small tooth at lateral fourth and another one a short distance laterad of the 1st; surface of clypeus with large subcontiguous punctures and numerous minute ones on the interspaces, the median lobe with a low process, conical when viewed from the side, the apical edge of the process forming a complete arcuate lamina; supraclypeal area slightly convex; rest of head except ventrally with contiguous punctures; 2nd flagellar segment slightly shorter (0.8) than 1st.

Thorax dull; pronotal dorsum, scutum, and scutellum with subcontiguous coarse punctures; tegula not inflated, with numerous small punctures; postscutellum with smaller, sparser punctures; anterior carina on lateral surface of pronotum not lamellate, attaining the dorsal surface but not extending onto it; mesopleuron with coarse contiguous punctures, not dentate or tuberculate; metapleuron with close oblique rugae except for a small punctate area above hind coxa; propodeal enclosure with some very short longitudinal rugae at base, a moderately deep, crenulate median groove, several large punctures along lateral impressed lines, the remainder of surface finely roughened; propodeum elsewhere coarsely and subcontiguously punctate, the concave area above attachment shallow, with 2 carinae gently arched outwardly on each side of midline.

Comb of fore basitarsus with 7 to 8 spines; hind tibia with 6 serrations.

Abdomen shining; 1st tergum subquadrate, sides rounded, the base slightly wider than apex, the surface with subcontiguous punctures; 2nd to 5th terga with similar punctures, the 4th slightly more sparsely so; pygidium barrel-shaped, the length half again as great as width, the surface strongly and irregularly wrinkled, with suberect sparse setae on basal half; 1st sternum with a rounded median keel on basal half; 2nd sternum not raised into a semicircular area at base, anterolaterally with a large, very shallow concavity; 5th sternum not gready swollen posterolaterally; hypopygium with apical teeth separated by a narrow U-shaped emargination, the lateral margin with a small acute tooth at middle.

MALE.—Length 7.5–11 mm, forewing 5.5–9 mm. Coloration similar to female except as follows: supraclypeal area occasionally yellow, vertexal spots tiny, temple with a spot above instead of a stripe, scutellar band occasionally interrupted, 3rd tergum occasionally immaculate, 6th tergum with an apical band, and 7th tergum with a lateral spot on each side adjacent to pygidium. Vestiture, wing color, and punctation also are essentially the same as described for the female.

Characters peculiar to the male are: head height 0.8 times the greatest width; eyes not convergent above or below, the interocular distances (as cited for female) subequal; clypeus gendy convex, the apical margin of median lobe feebly tridentate, the apical margin with a fimbria of curled, waxy-appearing hairs on lateral third; pygidium with sides parallel except at extreme base where they turn inward, the length 1.2 times the greatest width, the surface coarsely punctate, closely on basal two-thirds, more sparsely on apical third, the interspaces shagreened; sterna 5 and 6 without subbasal fimbriae; and hypopygium semicircularly emarginate at apex, the lateral teeth acute and slender.

Australia: 7♂, Prince of Wales Island, 14 February 1939, R. G. and C. Wind (USNM, the type series of insulicola Tsuneki).

Papua: 1♂, Kulumadau Hill, Woodlark Island, 25 February 1957, W. W. Brandt (BPBM). 2♀, K. B. Mission, Milne Bay, 6–17 and 19 March 1944, K. V. Krombein (KVK). 1♀, Waigani, Port Moresby, December 1942, W. G. Bodenstein (KVK). 1♂, Port Moresby, 13 May 1959, C. D. Michener (BPBM). 1♀, Otomata Plantation, east of Port Moresby, 1 m, 2 November 1960, J. L. Gressitt, in Malaise trap (BPBM). 1♀, Brown River, 5 November 1960, J. L. Gressitt, in rain forest (BPBM). 3♀, 15♂, Kokoda, 1200 ft, April (♀, 9♂), May (♂), August (2♀, 3♂), and September (2♂), 1933, L. E. Cheesman (BMNH). 1♂, Oquali, 4500 ft, July 1933, L. E. Cheesman (BMNH). 1♂, Kapagere, near Rigo, 14–19 May 1959, C. D. Michener (BPBM). 1♀, Mt. Lamington, May 1927, C. T. McNamara (AM), 1♀, Inonda, Horanda District, 8 December 1943, W. G. Bodenstein, (KVK).

Territory of New Guinea: 1♀, 4♂, Nadzab, Markham River Valley, 24 (♀, 3♂) and 27 (♂) August 1944, U. N. Lanham (KVK). 1♀, same locality but 9 December 1944, D. G. Hall (USNM).

The two specimens which I caught were taken in partial-to-open cleared areas, indicating that this is possibly a grassland or savannah form.