Leptophion giganteus Shimizu & Watanabe

Shimizu, So, Watanabe, Kyohei & Maeto, Kaoru, 2016, Revision of the Taiwanese species of the genus Leptophion Cameron, 1901 (Hymenoptera: Ichneumonidae: Ophioninae), with a discussion of their phenology and distribution, Zootaxa 4144 (1), pp. 71-88 : 79-82

Leptophion giganteus Shimizu & Watanabe , sp. nov.

( Figs 6 , 16–24 , 33 )

Spilophion radiatus Uchida, 1956: 18 . In part, misidentification (see Type series).

Type series. HT: female, Taiwan: Lixing Industry Rd, Ren’ai Township , Nantou County (24° 5' 41.7" N 121° 9' 53.7" E; ca. 1630 m alt.), 6. x. 2015, S. Shimizu & M. Ito leg. (LT) ( TARI) . PT: 1 female, Taiwan: Lixing Industry Rd, Ren’ai Township , Nantou County (24° 5' 41.7" N 121° 9' 53.7" E; ca. 1630 m alt.), 6. x. 2015, S. Shimizu & M. Ito leg. (LT) ( TARI) ; 1 female, Taiwan: Wulai , 31. iii. 1984, K. Ohara leg. ( NIAES) ; 1 female, Taiwan: Tungpu , Nantou County (1200m alt.), 10–14. i. 1983, K.C. Chou & S.P. Huang leg. ( TARI) ; 1 female, Taiwan: Shinten , 20. xii. 1927, K. Shibata leg. (PT of L. radiatus ) ( SEHU) .

Description. Female (n=5).

Head ( Figs 16–18 ) with FI=0.6–0.7 (HT: 0.7). Face 0.8 times as wide as high, weakly polished, entirely covered with dense punctures and hairs, with a longitudinal ridge on upper central area ( Fig. 16 ). Clypeus 0.5 (HT: 0.5) times as long as wide, polished with sparse punctures and fine hairs, strongly convex in lateral profile ( Fig. 18 ) and nearly straight in frontal view ( Fig. 16 ). Malar space 0.2–0.3 (HT: 0.3) times as long as basal width of mandible. Mandible weakly tapered, its basal and apical surfaces smooth and its median surface with sparse long hairs, basal margin with a swelling and an oblique groove ( Figs 16, 18 ). Upper and lower teeth of mandible same shape. Frons, vertex and gena polished with hairs. Posterior ocellus adjacent to eye ( Figs 16–18 ). Antennae with 69–75 (HT: 75) flagellomeres. First flagellomere 6.3–7.4 (HT: 7.2) times as long as wide and 1.9–2.3 (HT: 2.3) times as long as second flagellomere.

Mesosoma ( Figs 19, 20 ) moderately or strongly polished, entirely covered with hairs. Pronotum polished and smooth with fine hairs. Mesoscutum 1.4 (HT: 1.4) times as long as wide and evenly covered with fine dense punctures and hairs, without notauli ( Fig. 19 ). Scutellum with lateral longitudinal carinae developed on anterior 0.3 (HT: 0.3) ( Fig. 19 ). Epicnemium polished, entirely covered with punctures and hairs. Epicnemial carina present, its dorsal end not reaching anterior margin of mesopleuron ( Fig. 19 ). Mesopleuron and metapleuron polished with fine punctures and hairs. Submetapleural carina present. Propodeum in lateral profile rounded ( Fig. 19 ), with median longitudinal carinae and irregular rugae and with wide smooth area ( Fig. 20 ). Anterior transverse carina on propodeum sometimes absent laterally, or weak, and its outer end usually not joined to pleural carina ( Figs 19, 20 ).

Wings ( Figs 21 , 33 ). Fore wing 17.0–21.0 (HT: 20.6) mm with AI=1.1–1.4 (HT: 1.3); CI=0.2–0.3 (HT: 0.3); DI=0.5–0.6 (HT: 0.5); ICI=0.9–1.0 (HT: 0.9); SDI=1.1–1.3 (HT: 1.2) ( Fig. 33 ). 1m-cu of fore wing strongly sinuous ( Fig. 33 ). Proximal 0.4 of Rs+2r of fore wing broadened and slightly curved and distal 0.6 simple and straight ( Fig. 33 ). Discosubmarginal cell of fore wing with a glabrous area below pterostigma. Postero-distal corner of second discal cell of fore wing 105–110° (HT: 110°) ( Fig. 33 ). Hind wing with NI=1.5–1.8 (HT: 1.7) ( Fig. 33 ). Rs of hind wing nearly straight ( Fig. 33 ). Marginal cell of hind wing entirely setose except for a glabrous area above Rs. Proximal corner of marginal cell of hind wing about 45° ( Fig. 33 ). R1 of hind wing with 6 (HT: 6) uniform hamuli ( Fig. 21 ).

Legs ( Fig. 22 ). Hind coxa rounded and 1.8–1.9 (HT: 1.8) times as long as wide. Hind femur 0.7–0.8 (HT: 0.8) times as long as tibia. Inner tibial spur with a brush along its mesal side and distinctly longer than outer spur. Hind basitarsus 2.0–2.6 (HT: 2.3) times as long as second tarsomere. Distal pecten of hind tarsal claw developed and significantly longer than true apex of claw ( Fig. 22 ).

Metasoma polished with hairs and PI=2.3–2.6 (HT: 2.3); DMI=1.2–1.3 (HT: 1.3).

Male. Unknown.

Colouration ( Figs 6 , 33 ). Entirely pale yellow except for antenna, apex of mandible, vittae of mesoscutum, and metasoma as below. Antenna brown. Apex of mandible brown to black. Mesoscutum with three longitudinal vittae, both lateral vittae brown, middle vitta pale brown. T1 and T2 amber, T3 to T8 yellowish or light brown. Ovipositor brownish amber and its sheath dark brown. Venation of wings dark brown except for white part of pterostigma ( Fig. 33 ). Wings weakly infumate except for proximal part of marginal cell of fore wing often with a more or less strongly infumate area, but occasionally same as remainder of cell, and postero-proximal part of second subdiscal cell of fore wing with a distinct infumate area ( Fig. 33 ).

Variation. Length of fore wing 17.0–21.0 mm.

Distribution. Taiwan (Nantou County and New Taipei City) ( Fig. 35 )

Bionomics. Host is unknown. We collected the specimens in LT in a highly natural forest where coniferous and broadleaf trees were mixed ( Figs 23, 24 ).

Etymology. This is the largest species in this genus, hence the specific name is derived from the Latin “ giganteus ”, which means “giant”.

Remarks. This species belongs to the radiatus species-complex of the maculipennis species-group, characterized by the distal pecten of the hind tarsal claw developed and significantly longer than the true claw apex, and the uniform hamuli ( Gauld 1985).

This species resembles L. radiatus but it can be distinguished from it by the following character states: (1) postero-distal part of second discal cell of fore wing generally obtuse, about 105–110o (it is generally acute, about 85o in L. radiatus ); (2) fore wing with AI=1.1–1.4, ICI=0.9–1.0, SDI=1.1–1.2 (AI=0.9–1.0, ICI=0.6–0.7, SDI= 0.8– 0.9 in L. radiatus ); (3) 1m-cu of fore wing strongly sinuous (1m-cu of fore wing abruptly curved in L. radiatus ); (4) fore wing weakly infumate with an infumate area on second subdiscal cell (fore wing hyaline with a partial infumate area in the marginal cell and second subdiscal cell in L. radiatus ); and (5) fore wing 17.0–21.0 mm (fore wing 13.0–15.0 mm in L. radiatus ).

We propose the additional couplets below (*) for the key to Indo-Papuan species of Leptophion provided by Gauld & Mitchell (1981):

10 (9). Lateral longitudinal carinae of scutellum reaching behind centre; fore wing with 1m-cu strongly sinuous with a trace of ramellus discernible..................................................... L. vechti Gauld & Mitchell, 1981

- Lateral longitudinal carinae of scutellum present only on anterior 0.2; fore wing with 1m-cu unevenly curved without a vestige of a ramellus.............................................................................*11

*11 (10). Flagellum proximally black; second subdiscal cell of fore wing entirely hyaline; postero-distal corner of second discal cell of fore wing about 105o; Papuan.................................. .. L. cheesmanae Gauld & Mitchell, 1981

- Flagellum proximally reddish-brown; postero-proximal corner of second subdiscal cell of fore wing with an infumate area; postero-distal corner of second discal cell of fore wing about 85–110o; Oriental..........................*12

*12 (*11). 1m-cu of fore wing strongly sinuous. Postero-distal corner of second discal cell of fore wing making an obtuse angle, about 105–110°. Fore wing with AI=1.1–1.4; ICI=0.9–1.0; SDI=1.1–1.2. Fore wing weakly infumate except for proximal part of marginal cell often with a more or less distinct infumate area, but occasionally not more infumate than rest of cell, and postero-proximal part of second subdiscal cell with a distinct infumate area. Fore wing 17.0–21.0 mm......................................................................... L. giganteus Shimizu & Watanabe , sp. nov.

- 1m-cu of fore wing abruptly curved. Postero-distal corner of second discal cell of fore wing making an acute angle, about 85°. Fore wing with AI=0.8–0.9; ICI=0.5–0.7; SDI=0.9–1.0. Fore wing hyaline except for proximal part of marginal cell and postero-proximal corner of second subdiscal cell each with infumate areas. Fore wing 13.0–15.0 mm...................................................................................... L. radiatus ( Uchida, 1956)

Figures

FIGURE 35. Distribution of Leptophion in Taiwan.

FIGURES 5 – 7. Lateral habitus of Leptophion occurring in Taiwan. 5, L. maculipennis; 6, L. giganteus Shimizu & Watanabe, sp. nov. (HT); 7, L. radiatus. Scale bar: 5.0 mm.

FIGURES 16 – 22. Partial views of a PT (female) of L. giganteus Shimizu & Watanabe, sp. nov. 16 – 18, head in frontal (16), dorsal (17), and lateral (18) views; 19, mesosoma in lateral view; 20, propodeum in dorsal view (omitted surface sculptures on anterior area and right side); 21, hamuli on R 1; 22, outer tarsal claw of hind leg.

FIGURES 23, 24. The habitat (23) and LT collection (24) of L. giganteus Shimizu & Watanabe, sp. nov. on 6. x. 2015 at Lixing Industry Rd, Ren’ai Township, Nantou County, Taiwan (24 ° 5 ' 41.7 " N 121 ° 9 ' 53.7 " E; ca. 1630 m alt.).

FIGURES 32 – 34. Wings of female Leptophion from Taiwan. 32, L. maculipennis; 33, L. giganteus Shimizu & Watanabe, sp. nov. (PT); 34, L. radiatus. Scale bar: 3.0 mm.