Xiphydria kanba Shinohara, Hara & Smith, 2020

Shinohara, Akihiko, Hara, Hideho & Smith, David R., 2020, The Xiphydria annulitibia group in northeastern Asia (Hymenoptera, Xiphydriidae), Zootaxa 4755 (2), pp. 375-389 : 382-384

Xiphydria kanba Shinohara, Hara & Smith , n. sp.

( Figs 2 , 3 D–F, 4B, 5B, 6)

Description. Female (holotype, Figs 3 D–F, 4B, 5B). Length without ovipositor about 11.5 mm. Head black, with paired spots on anterior part of vertex (behind lateral ocelli), spot on each lateral posterior part of vertex, elongate mark along lower inner orbit to malar space, and spot on lower part of gena creamy white ( Figs 2 A–F, 3D–F). Mouth parts blackish brown to black; ligula mostly whitish and mandible dark brownish gray medially. Antenna entirely black. Thorax entirely black. Legs black; narrow base of fore tibia, basal half of mid tibia dorsally, most of mid tarsomere 1 dorsally, basal 2/3 of hind tibia dorsally, and most of hind tarsomere 1 dorsally creamy white. Wings hyaline, with apical 1/3 rather obscurely darkened (darkest part under stigma); veins and stigma blackish brown. Abdomen black, with lateral creamy white spots on terga 2–5; ovipositor sheath with very narrow apex pale brown.

Malar space about 0.5× length of distance between toruli, with ventral pit rather shallow, sharply delimited by carina only on anterior margin; occipital carina (crassa) distinct, entire; genal carina developed nearly to vertex but their dorsal ends widely separated from each other; inner orbits subparallel, interocular distance at level of toruli about 1.4× eye height; wide longitudinal depression from median ocellus to median fovea. Labial palpus with 3 palpomeres; maxillary palpus with 5 palpomeres. Both antennae with 15 antennomeres; scape (incl. radicula):pedicel:flagellomere 1:flagellomere 2 as 3.3:1.0:2.3:1.2. Hind tarsomere 1 about 0.9× length of remaining tarsomeres combined; tarsal claws with large inner tooth. Forewing with cell 3R1 closed at apex (vein R1 connecting with vein Rs); cell 2Rs much narrower than cell 1M; crossvein 2r-m apical to crossvein 2m-cu on vein M; hindwing with cell R1 closed and angled at apex ( Fig. 4B ). Abdominal tergum 10 normal, not directed dorsally at apex in lateral view ( Fig. 5B ). Ovipositor sheath with apical sheath subequal in length to basal sheath.

Frons and interantennal area reticulate, with rather conspicuous striae radiating down from ocelli; gena covered with rough longitudinal wrinkles and some large punctures; vertex smooth, shiny, anterior part (anterior subtriangular part of postocellar area and area just behind upper orbit) minutely rugose with sparse punctures, not shiny ( Figs 2 A–F; 3D–F). Pronotum irregularly wrinkled in dorsal half, smooth with several longitudinal ridges at middle, and very smooth and impunctate in ventral half; propleuron roughly wrinkled but without distinct punctures and surface rather smooth; mesoscutal median lobe coarsely reticulate on dorsal surface; lateral lobes reticulate with large elongate even area with coriaceous and mat surface and with some small irregular punctures; mesoscutellum densely rugoso-reticulate; mesepisternum rather shallowly rugoso-reticulate, pilose; mesepimeron nearly impunctate and glabrous, coarsely and obliquely wrinkled; metepisternum and metepimeron coarsely rugoso-reticulate. Abdomen with tergum 1 coarsely finely punctate, each half centrally and with broad inner margin nearly impunctate and shining; all other terga weakly shining with very fine surface microsculpture.

Male (paratype with same data as holotype). Length about 9.0 mm. Similar to female in color and structure ( Fig. 2 ), except as follows: Mandible largely pale brownish; antennal scape and pedicel partly dark brown; pronotum with creamy white marks on lateral dorsal margin, posterior margin and ventral margin; propleuron with large creamy white mark on lateroventral surface; legs black with blackish brown marks, without creamy white area. Both antennae with 14 antennomeres; abdominal sterna 4–8 each with group of long golden setae in posterior part medially (more conspicuous in lateral view, Fig. 2H, J ); tergum 9 without distinct median longitudinal keel, narrowly rounded at apex.

Variation. Female: The length without ovipositor varies from 6.5 to 13.5 mm. The color pattern shows slight variation as follows: The pale spots on the vertex are rarely absent. The pale mark on the lower inner orbit to malar space is often connected with the spot on the lower gena. On the other extreme, the pale spot on the lower gena is entirely missing. The mandibles are sometimes almost entirely black. Abdominal tergum 8 is sometimes marked with creamy white laterally ( Fig. 2B ). The antenna usually has 14 or 15 antennomeres (n=87; 13 or 16 antennomeres in 3 antennae). The apical sheath is about 1.0–1.2 × as long as the basal sheath (n=46). Male: The length ranges from 6.5 to 12.5 mm. The color pattern varies little. The paired pale spots on the vertex are rarely missing ( Fig. 2K ). Abdominal tergum 1 and posterior part of the mesepisternum rarely have small obscure creamy white marks. Abdominal tergum 6 sometimes has a small creamy white spot on each lateral side. The antenna usually has 14–16 antennomeres (n=115; 17 antennomeres in 4 antennae). Numbers of the labial and maxillary palpomeres are constant in both sexes. The venational characters given in the description above vary little, though crossvein 2r-m is sometimes interstitial with (but never basal to) crossvein 2m-cu on vein M.

Type material examined (49♀ 70♂ from Hokkaido and 1♀ from Honshu). Holotype: ♀, Horobinai , 42°48’01’’N 141°19’20’’E, ca. 280 m alt., near Shikotsu-ko, Chitose, Hokkaido, emerged 25. VII. 2019 from dead branch of Betula ermanii collected 20. VII. 2019, A. Shinohara & H. Hara ( NSMT) . Paratypes: HOKKAIDO: 1♂, Koshu- nai, Bibai, 12–22. VII. 2002, Malaise trap, H. Hara ( NSMT); 2♂, em. from fallen branches of Betula platyphylla var. japonica , July 2014, Hokkaido Univ. Campus [43°4’41.77’’N 141°20’20.14’’E, ca. 12 m alt.], Sapporo, site #20-1 (Kyoshoku-ura, Kogakubu Power Center-ura), M. Shizuki & T, Yoshida ( USNM); 1♂, Hokkaido Univ. Campus, Sapporo, dead branch collection: April, T. Yoshida & M. Shizuki, emergence box: 15-7a-6, Betula platyphylla var. japonica , em. 30. VI.–15. VII. 2015, site #20-1 (Kyoyo-ura), 2–3.5 cm ( USNM); 7♀ 5♂, same data except emergence box: 15-8a-6, 3.5 cm <( USNM); 2♂, same data except emergence box: 15-8a-7, Betula platyphylla var. japonica , em. 15–31. VII. 2015, 3.5 cm <( USNM); 1♂, Nijigaoka, Kitahiroshima, 1. VIII. 2015, M. Shizuki ( USNM); 2♀ 8♂, same locality as holotype, 20. VII. 2019, A. Shinohara ( NSMT); 1♀ 2♂, same locality as holotype, 20. VII. 2019, H. Hara ( NSMT); 5♀ 8♂, same data as holotype except emerged 21. VII. 2019 ( NSMT); 1♀ 3♂, same data except emerged 22. VII. 2019 ( NSMT); 1♀ 4♂, same data except emerged 23. VII. 2019 ( NSMT); 3♀ 1♂, same data except emerged 24. VII. 2019 ( NSMT); 2♀ 2♂, same data as holotype ( NSMT); 3♀ 1♂, same data except emerged 26. VII. 2019 ( NSMT); 1♀, same data except emerged 27. VII. 2019 ( NSMT); 1♂, same data except emerged 28. VII. 2019 ( NSMT); 2♀ 8♂, same data as holotype except H. Hara & A. Shinohara ( NSMT); 1♀ 2♂, same data except emerged 22. VII. 2019 ( NSMT); 1♂, same data except emerged 23. VII. 2019 ( NSMT); 7♂, same data except emerged 24. VII. 2019 ( NSMT); 5♀ 5♂, same data except emerged 25. VII. 2019 ( NSMT); 3♀ 5♂, same data except emerged 26. VII. 2019 ( NSMT); 2♀, same data except emerged 27. VII. 2019 ( NSMT); 5♀, same data except emerged 28. VII. 2019 ( NSMT); 2♀, same data except emerged 29. VII. 2019 ( NSMT); 1♀, same data except emerged 2. VIII. 2019 ( NSMT); 1♀, Naka-toya [42°37’0.33’’N 140°55’6.21’’E, ca. 100m alt.], near Lake Toya , [Sobetsu-cho], 12–13. VIII. 1979, Y. Seiyama ( EU). HONSHU: Tochigi Pref.: 1♀, Chûgûshi, 36°44’46’’N 139°28’23’’E, ca. 1300 m alt., near Chûzenji-ko, Nikko, emerged 10. VIII. 2019 from dead branch of Betula platyphylla var. japonica collected 7. VIII. 2019, A. Shinohara ( NSMT) .

Distribution. Japan (Hokkaido, Honshu).

Host plant. Betulaceae : Betula platyphylla Sukaczev var. japonica (Miq.) H.Hara ; Betula ermanii Cham.

Etymology. The specific epithet “ kanba ” is a Japanese name for birch, the host plant. It is a noun in apposition.

Branch trapping and adult behavior. On July 20, 2019, Hara and Shinohara collected two dead and fallen branches of Betula ermanii in Horobinai ( Fig. 6A , branches were found at the edge of the forest on the right side in the picture). These two fallen branches drew our attention, because several individuals of X. kanba were found staying on the branches or nearby. A total of 86 adult xiphydriids emerged from these branches during the period from July 21 to August 2, 2019 (see material examined above for more details). The two branches are as follows:

Branch A. Apically bifurcate. The basal unbranched part was about 186 cm long and 2.1–4.2 cm thick and the two apical branches were 42 cm long and 0.8–1.9 cm thick and 43 cm long and 1.2–2.1 cm thick, respectively. The whole branch was cut into nine pieces for transportation; five pieces were brought to Bibai by Hara and four pieces were brought to Tsukuba by Shinohara. Almost all the xiphydriids emerged from the thicker basal part (basal 110 cm of the branch, 2.7–4.2 cm in diameter), a few emerged from the apical unbranched part (about 76 cm long and 2.0– 2.7 cm thick), and none emerged from the apical two branches (42 or 43 cm long and 2.1 cm or less in diameter).

Branch B. About 106 cm long, with no branching. The basal thickest end was about 5.0 cm in diameter and the apical thinnest end was about 4.5 cm in diameter. We cut the branch into three pieces, two of them taken to Bibai by Hara and the remaining one taken to Tsukuba by Shinohara. Xiphydriids emerged from all parts of the branch. From this branch, four females and 15 males of a siricid, Tremex fuscicornis ( Fabricius, 1787) , also emerged during the period from 5 to 19, August, 2019.

It seems clear that X. kanba feeds mainly in branches of 2.7–5.0 cm thick and not in branches thinner than 2.0 cm. The label data show that the series of specimens from Sapporo emerged from dead and fallen branches of 2.0– 3.5 cm thick.

On July 24 and 25, Shinohara observed emergence of the adults from the branch. On July 24, a xiphydriid was apparently emerging from the branch at about 18:25. When it was found, the head was outside of the hole but the insect soon returned into the hole. About 18:50, the head of the xiphydriid was coming out again ( Fig. 6B ), but it went back into the hole in a few minutes. About 19:15, observation stopped for a few minutes; when observed again, the adult already had emerged and was staying on the branch. On July 25, Shinohara happened to see the face of a xiphydriid in a hole on the branch at about 14:17 ( Fig. 6C ). For more than 15 minutes, the xiphydriid did not come out but kept its head somehow moving near the entrance of the hole, seemingly trying to enlarge the hole by biting with its mandibles ( Fig. 6D, E ). At about 14:36, the xiphydriid suddenly and quickly came out of the hole ( Fig. 6 F–J).

On July 23, Shinohara observed a “drumming” behavior of a male adult in the plastic bag, where three pieces of Branch A were stored. The emerged male, while walking, tapped his abdomen on the wall of the plastic bag rhythmically, making a fairly large crackle sound well noticeable at a distance of 1 m from the bag in the silent room. This large sound was made simply because the wall of the plastic bag worked as a drum, and the sound would not be heard if the male tapped his abdomen on the surface of the branch in the field. This “drumming” may be part of the courtship behavior and may have some connection with the presence of hair tufts on the abdominal sterna of the male.

Remarks. This new species is easily recognized by the features given in the key. The venational characters are always subject of some variations in the Xiphydriidae , but the small size of cell 2Rs and the basal position of the 2m-cu crossvein on the vein M in the forewing of this species ( Fig. 4B ) seem to be fairly stable and serve as good distinguishing characters. The male is known only for this species in the X. annulitibia group. In the males, X. kanba is separated from the three species of the X. camelus group ( Shinohara & Kameda 2019) in having hair tufts on the abdominal sterna. The males of the three species of the X. palaeanarctica group (Shinohara 2019) also have hair tufts on the abdominal sterna, but the males of X. palaeanarctica Semenov-Tian-Shanskij, 1921, and X. nagasei Shinohara, 2019 , have partly whitish antennae and the male of X. ogasawarai Matsumura, 1927 , has largely pale brownish legs and a dorsally keeled and apically pointed subtriangular abdominal tergum 9.

Figures

FIG. 2. Xiphydria kanba, female (A–F) and male (G–M), paratopotypes.—A, G, Dorsal view; B, H, I, lateral view (I, showing lateral pale spots on abdomen); C, J, ventral view; D, K, head, dorsal view; E, L, head, frontal view; F, M, head lateral view.

FIG. 3. Heads, females, Xiphydria annulitibia, holotype (A–C), X. kanba, holotype (D–F), X. konishii, holotype (G–I) and X. melanoptera, holotype (J–L).—A, D, G, J, Dorsal view; B, E, H, K, frontal view; C, F, I, L, frontolateral view.

FIG. 4. Xiphydria annulitibia (A) and X. kanba (B), females, holotypes, wings, with names of cells (A) and veins and crossveins (B). Four large arrows show open or nearly open (A) or closed (B) apices of cell 3R1 in forewing and cell R1 in hindwing.

FIG. 5. Apical parts of abdomens, holotypes, lateral view.—A, Xiphydria annulitibia; B, X. kanba; C, X. konishii; D, X. melanoptera.

FIG. 6. A, View of the type locality of Xiphydria kanba in Horobinai, August 24, 2019; B, a female emerging, July 24, 2019; C–J, another female, emerging, July 25, 2019.