Pristaulacus japonicus Turrisi & Watanabe

Turrisi, Giuseppe Fabrizio & Watanabe, Kyohei, 2011, Description of two new Asian Pristaulacus Kieffer 1900 (Hymenoptera: Aulacidae), Zootaxa 2895, pp. 35-46 : 36-41

Pristaulacus japonicus Turrisi & Watanabe , sp.n.

( Figs 1–13 )

Type material. JAPAN: holotype Ƥ labelled “( Japan) Nagano Pref., Outaki-mura, Mt. Ontake-san, Hakkaisan, 35- 51-47N/137-31-37E, 7.Aug. 2010 (1660–1700 m alt.), Kyohei Watanabe leg./ Pristaulacus japonicus Turrisi & Watanabe sp.n. Ƥ 2010 Holotypus ” ( TUAE); 1 paratype 3, same data as holotype ( UCCT); 1 paratype 3, same data as holotype except date, 8.VIII.2010, and collector, Yoshie Kaga ( TUAE).

Etymology. The name refers to Japan, a noun in apposition.

Description (holotype, Ƥ). Length: 13.1 mm; antenna length: 11.7 mm; fore wing length: 9.7 mm; ovipositor length: 22.7 mm.

Colour mainly black, except: distal margin of clypeus reddish orange; mandible extensively reddish orange with teeth darker; maxillo-labial complex with last three maxillary palpomeres orange; fore and mid femora, tibiae and tarsi (except pretarsi darker) orange; hind femur dark brown; hind tarsus yellow orange (except pretarsus darker); wings hyaline yellowish, with veins and stigma orange, except vein Sc+R+Rs black; metasoma with base of T2 dark reddish orange. Setae white, golden on mandible.

Head, from above, 1.2× wider than long, dull to shiny; occipital margin straight; temple, from above, well developed, weakly convex, about 0.9× as long as eye length; occipital carina narrow, 0.2–0.3× diameter of an ocellus; POL:OOL= 1.3; ocellar area 2.1× wider than long; vertex and upper half of temple punctate-coriarious with fine, deep and dense punctures (distance between punctures 1.0–3.0× puncture diameter); lower temple, behind eye, with coarse, deep and scattered to dense punctures (distance between punctures 2.0–5.0× puncture diameter); upper half of frons transverse-striolate with fine to coarse, deep and dense punctures (distance between punctures about 1.0–2.0× puncture diameter); lower half of frons partly with fine, deep and very dense punctures (distance between punctures 0.2× puncture diameter), less dense on subantennal area; clypeus with coarse, deep and dense punctures; anterior half of malar area obscurely-variolate-punctate, posterior half partly polished and impunctate (basal) and partly rugulose-punctate; occipital area polished-punctate; antenna 1.2× fore wing length; A3 7.5× longer than wide; A4 14.2× longer than wide, and 1.8× longer than A3; A5 13.7× longer than wide, and 1.6× longer than A3. Setae semi erect to erect, moderately long and moderately dense on vertex; semi erect to erect, long and dense on temple (length of setae 1.0–1.1× diameter of an ocellus); erect, long and dense on upper frons; recumbent, long and dense on lower frons, less dense on clypeus; recumbent, moderately long and dense on malar area.

Mesosoma weakly sculptured; pronotum mostly polished-punctate, oblique-carinulate in middle, with lateroventral margins rounded; propleuron polished and shiny with coarse, deep and dense punctures on dorsal surface, coarse, superficial to deep and dense punctures on ventral surface (distance between punctures about 1.0–2.0× puncture diameter); prescutum triangular, wide, long, convex, confused rugulose-punctate, except on base, polished-punctate; mesoscutum polished-punctate to transverse-carinulate; dorsally not prominent, anterior margin not prominent and rounded (lateral view); notauli deep and narrow; scutellum transverse-carinate in middle, areolate-rugose on anterior margin and posterolateral corners; mesopleuron mostly rugulose-foveolate with some sparse carinulae; metanotum confused-carinulate in middle weakly scrobiculate on sides; propodeum with anterior margin longitudinally carinate, dorsal surface irregularly carinate, lateral surfaces mostly confused areolate-rugosefoveolate, posterior part of lateral surfaces and posterior surface irregularly longitudinally carinate with two wide and short lamelliform tooth-like processes along a strong transverse carina on sides of posterior surface, above middle; venter of mesosoma mostly rugulose-foveolate, with a few transverse carinulae, scrobiculate in middle; fore wing with vein 2–rs+m long; coxa I polished-punctate with coarse, superficial and dense punctures on ventral surface; coxa II transverse-carinulate-punctate on dorsal surface, with fine, deep and dense punctures, polishedpunctate to rugulose-punctate on ventral surface, with coarse, deep and dense punctures; coxa III transversestrigate to transverse-carinulate and punctate, with coarse, deep and dense punctures (on base) on dorsal surface, transverse-strigate-punctate to transverse-carinulate-punctate on ventral surface, with coarse, deep and dense punctures (distance between punctures 2.0× puncture diameter); spurs of mid and hind tibiae subequal in length; hind basitarsus 12.7× longer than wide, and 1.3× as tarsomeres 2–5; tarsal claw with three tooth-like processes, basal one very weak, poorly visible. Setae erect, short and scattered on dorsal mesoscutum, semi erect, long and dense on remaining dorsal surface; recumbent to erect (on upper part of pronotum), short to long (on pronotum) and dense on sides and ventral part of mesosoma; erect, long and scattered to dense on hind surface of propodeum; erect, long and dense on propleuron (setae length at most about 0.7× pretarsus length).

Metasoma pyriform (lateral view), very elongate, compressed laterally; petiole elongate, slender, 3.8× longer than wide; segment 1 polished and shiny, with a few sparse punctures; following segments finely microsculptured, with fine, deep and dense punctures on middle of tergites and sternites; S7 finely longitudinally strigate, with fine to coarse and dense punctures; T8 microsculptured with fine, deep and scattered to dense punctures; ovipositor very long, 2.3× longer than fore wing length. Setae: segment 1 glabrous; recumbent, very short and scattered on T2; recumbent, very short and dense on middle of following tergites and sternites; semi erect, short and dense on S7.

3 (paratype). Length: 12.9 mm; forewing length: 8.8 mm. Colour, structure, and setae like Ƥ, except: clypeus entirely and mandible extensively orange yellowish; A1 reddish orange; antenna only slightly longer than fore wing length; A3 4.0× longer than wide; A4 7.6× longer than wide, and 1.9× longer than A3; A5 7.4× as long and 1.8× longer than A3; A13 subcylindrical, with apex slightly acute, 4.8× longer than wide; hind basitarsus 1.2× as tarsomeres 2–5; petiole 5.0× longer than wide.

Intraspecific variation. Length: 12.9–13.0 mm (3); fore wing length: 8.8–9.3 mm (3). One paratype has the hind femur lighter than remaining type specimens.

Remarks. This species is readily separated from other Palaearctic Pristaulacus by the following combination of characters: upper half of frons transverse-striolate ( Fig. 3 ); tarsal claws with three equally spaced tooth-like processes along inner margin, the basal one very weak, poorly visible ( Fig. 10 , detail); mesosoma weakly sculptured, with mesoscutum polished-punctate to transverse-carinulate ( Figs 5–6 ); wings uniformly yellowish hyaline without dark spots and with vein 2–rs+m long ( Fig. 8 ); ovipositor very long, more than 2.0× fore wing length.

It is similar to P. gibbator , which is widespread throughout Eurasia, the eastern-most record being Siberia ( Russia), and fits in couplet 15 in the key to Palaearctic Pristaulacus ( Turrisi 2007) . These two species are indeed very similar, sharing the colour pattern; upper frons weakly sculptured; antenna longer than fore wing; mesosoma weakly sculptured; hind coxa elongate, slender; presence of three tooth-like processes along inner margin of tarsal claws; and ovipositor very long (quite more than 1.5× fore wing length). The two species also share another interesting character, the presence of a tooth-like process on each side of the hind surface of the propodeum ( Fig. 7 ). These two processes originate from the lateral most part of the medial transverse carinae of the propodeum and are variable in size, from weak and hardly recognizable to well developed. Among the Palaearctic Pristaulacus , only P. superbus Turrisi & Konishi 2011 , described from Japan ( Turrisi & Konishi 2011), shares this character; however, in this species the two tooth-like processes are more conspicuous. The differences between P. Japonicus and P. Gibbator are mostly subtle and seem to indicate that they are sibling species. After comparing female and male specimens of the two species (material of P. gibbator from BMNH, NHRS, UCCT), the following main differences are recognized: sculpturing of upper mesopleuron, polished-punctate to weakly carinulate-punctate, punctures fine to coarse, superficial and scattered (both Ƥ and 3) vs. extensively rugulose with coarse, deep and dense punctures in P. gibbator ; sculpture of upper metapleuron weakly rugulose-punctate (both Ƥ and 3) vs. strongly oblique-carinate-punctate in P. gibbator ; petiole slightly longer, Ƥ: 3.8×; 3: 5.0× longer than wide vs. Ƥ: 3.2×; 3: 4.5× longer than wide in P. gibbator ; ovipositor longer, 2.3× fore wing length vs. 1.8–2.0× in P. gibbator ; and features of male genital capsule ( Figs 12–13 ): shape of the apex of the paramere, obliquely truncated, not emarginated in middle vs. obliquely truncated, slightly emarginated in middle in P. gibbator ( Figs 14–15 ), shape of lamina volsellaris and of penis valve ( Figs 13, 15 ).

Distribution. Japan (Honshu), known only from type locality.

Biology. Specimens of P. japonicus were collected around trees of Larix kaempferi Sargent (Pinaceae) ( Figs 16–17 , K. Watanabe field observation). There are no data on hosts, although several Cerambycidae (Coleoptera) are known as xylophagous feeders on that tree species, namely: Callidium (Palaeocallidium) kuratai Yokoyama , Necydalis sachalinensis Matsushita & Tamanuki , Leptura vicaria (Bates) , and Corymbia variicornis (Dalman) . It is interesting that the closely related Pristaulacus gibbator oviposits in wood of Pinaceae , but Picea abies L. (Karst) and, so far as is known, parasitizes the longhorn beetle Callidium (Palaeocallidium) coriaceum (Paykull) ( Turrisi 2007) .

Figures

FIGURES 1 – 4. Pristaulacus japonicus Turrisi & Watanabe, sp. n. (holotype Ƥ, Japan): 1, habitus; 2, head dorsal view; 3, head frontal view; 4, head lateral view.

FIGURES 5 – 7. Pristaulacus japonicus Turrisi & Watanabe, sp. n. (holotype Ƥ, Japan), mesosoma: 5, dorsal view; 6, lateral view; 7, propodeum, latero-posterior view.

FIGURES 8 – 11. Pristaulacus japonicus Turrisi & Watanabe, sp. n. (holotype Ƥ, Japan): 8, wings; 9, mid and hind coxae, ventral view; 10, hind tarsus, lateral view and detail of tarsal claws; 11, metasoma, lateral view.

FIGURES 12 – 15. Genital capsule of Pristaulacus japonicus Turrisi & Watanabe, sp. n. (paratype ♂, Japan) (12 – 13) and, P. gibbator (Thunberg 1822), specimen from Sweden (NHRS) (14 – 15). 12 – 14, paramere, inner view; 13 – 15, detail of lamina volsellaris, inner view, and penis valve, outer view. Scale bars = 0.2 mm.

FIGURES 16 – 17. Habitat of findings of Pristaulacus japonicus Turrisi & Watanabe, sp. n. (Japan: Mt. Ontake-san, Hakkaisan): 16, general view; 17, bark-less tree of Larix kaempferi Sargent, place of findings of aulacids.