Tersilochinae (Hymenoptera: Ichneumonidae) of Costa Rica, part 2. Genera Megalochus gen. nov. and Stethantyx Townes Author Khalaim, Andrey I. Author Broad, Gavin R. text Zootaxa 2013 3693 2 221 266 journal article 10.11646/zootaxa.3693.2.8 36ea2224-55a8-4117-aba3-bfd3178f9b58 1175-5326 249392 72B60375-3DF1-4EB1-B15E-587FDB6206BF Key to species of Stethantyx occurring in Costa Rica * *The key works well for females and also can be used for identification of some males, but additional comparison of males with species descriptions and with identified females is strongly recommended. 1 Flagellum of antenna black with pale band ( Fig. 14 ).......................................................... 2 - Flagellum of antenna pale brown to black, without pale band................................................... 5 2 Mesosoma black.......................................................................... cecilia sp. nov. - Mesosoma reddish orange.............................................................................. 3 3 Head black with clypeus, face and malar space yellow ( Fig. 11 ). Notaulus as groove (often with crest or tubercle before groove) somewhat distant from anterolateral margin of mesoscutum ( Figs 24, 25 ). Face with strong central prominence. Scutellum with lateral longitudinal carinae long, reaching its posterior end, but usually not joining posteriorly ( Fig. 25 ). Apical area of propodeum with wrinkles peripherally, anteriorly broad. Tergite 2 of female about 1.5× as long as anteriorly broad.......................................................................................... alajuela sp. nov. - Head orange to brownish orange with clypeus and sometimes also face yellowish. Notaulus absent ( Fig. 48 ) or represented by a small tubercle ( Fig. 32 ). Face with weak central prominence. Scutellum with lateral longitudinal carinae extending from its base to posterior 0.5–0.7 ( Fig. 48 ). Apical area of propodeum evenly granulate, without transverse wrinkles, narrowly pointed or rounded anteriorly ( Figs 33 , 49 ). Tergite 2 of female 1.5–2.3× as long as anteriorly broad.......................... 4 4 Hind femur and tibia blackish. Basal part of propodeum long and narrow, distinctly widened anteriorly (basal longitudinal carinae often distinct only posteriorly) ( Fig. 33 ); apical area more or less pointed anteriorly ( Fig. 33 ). First tergite with petiole orange, postpetiole black; tergites 2+ dark brown to black, posteriorly white marked; apex of metasoma more or less entirely white. Notaulus represented by a small tubercle ( Fig. 32 ). Tergite 2 of female more than twice as long as anteriorly broad. Ovipositor sheath about twice as long as first tergite.......................................... .. guanacasteca sp. nov. - Hind femur orange, tibia orange or sometimes fuscous. Basal area of propodeum short and broad, but often its longitudinal carinae indistinct, and basal area covered by weak longitudinal wrinkles ( Fig. 49 ); apical area anteriorly rounded or truncated ( Fig. 49 ). Metasoma predominantly orange; tergite 1 usually unicoloured but sometimes postpetiole is darker than petiole; tergites 2 and 3 dorsally brown to black but sometimes metasoma largely darkened dorsally. Notaulus usually completely absent ( Fig. 48 ) or rarely represented by a very small tubercle. Tergite 2 of female usually 1.5–1.8× as long as anteriorly broad, but rarely up to 2.2 ×. Ovipositor sheath 1.4–1.8× as long as first tergite........................ .. puntarenasa sp. nov. 5(1) Mesosoma entirely black (anterior margin of pronotum sometimes whitish). Malar space very short, about 0.1× as long as basal width of mandible. Ovipositor at apex with distinct teeth dorsally and fine teeth ventrally ( Fig. 40 )..... niger sp. nov. - Mesosoma entirely or predominantly orange, sometimes mesoscutum, scutellum and propodeum dark reddish brown or black. Malar space usually longer, at least 0.2× as long as basal width of mandible (except S. aprica ). Ovipositor at apex with weak dorsal depression, without distinct teeth................................................................... 6 6 Mesoscutum and scutellum entirely black, conspicuously darker than mesopleuron ( Figs 58 , 64 )..................... 7 - Mesoscutum and scutellum orange, more or less the same colour as mesopleuron; sometimes mesoscutum infuscate centrally.................................................................................................... 8 7 Propodeum black, with clearly delimited basal area ( Fig. 65 ). Head black (except clypeus)............. tenoriosa sp. nov. - Propodeum brownish yellow, without delimited basal area, with some longitudinal wrinkles dorsally ( Fig. 59 ). Upper half of head black, face and lower half of temple brownish yellow ( Fig. 58 )............................ mesoscutator sp. nov. 8(6) Head entirely or predominantly orange ( Fig. 13 ), clypeus and face sometimes yellowish, frons and anterior part of vertex sometimes blackish. Propodeum with long and narrow basal area which is weakly widened anteriorly ( Fig. 53 ); apical area pointed or narrowly rounded anteriorly................................................................... 9 - Head black, face and clypeus sometimes yellowish ( Figs 12 , 16–19 ). Areolation of propodeum usually not as above...... 10 9 Frons and vertex orange, only interocellar area sometimes fuscous. Ovipositor sheath 1.4–1.9× as long as first tergite. Flagellum of antenna with 25–34 flagellomeres..................................................... sanjosea sp. nov. - Frons and anterior part of vertex blackish. Ovipositor sheath about 3.1× as long as first tergite. Flagellum of antenna with 25– 26 segments.......................................................................... cacaoensis sp. nov. 10(8) Face yellowish ( Fig. 12 ). Propodeum with basal keel which is rarely indistinct ( Fig. 36 ); apical area anteriorly usually pointed ( Fig. 36 ). [Notaulus as small anterolateral tubercle ( Fig. 35 ), or in small specimens completely absent. Ovipositor sheath about 1.5× as long as first tergite.]................................................................ heredia sp. nov. - Face black ( Figs 17, 19 ). Propodeum with narrow or broad basal area which is sometimes indistinct, or with basal furrow; apical area anteriorly sometimes widely rounded or truncate ( Figs 44 , 52 ).......................................... 11 11 Flagellum of antenna basally very slender, flagellomere 2 more than twice as long as broad ( Fig. 16 ). Lateral carinae of scutellum very short, developed only at extreme base of scutellum. Ovipositor weakly but distinctly sinuate at apex ( Fig. 31 ), its sheath sheath more than 3.0× as long as first tergite.......................................................... 12 - Flagellum of antenna basally less slender, flagellomere 2 at most 1.7× as long as broad ( Fig. 19 ). Lateral carinae of scutellum usually longer, sometimes extending to hind margin of scutellum and joining posteriorly. Ovipositor more or less evenly upcurved, not sinuate at apex, its sheath usually much shorter.................................................. 13 12 Mesopleuron and dorsolateral area of propodeum evenly granulate, dull and very finely punctate. Propodeum with basal area, without impressed furrow dorsally ( Fig. 30 ). Foveate groove of mesopleuron weak. Ovipositor about as long as body............................................................................................. curvator sp. nov. - Mesopleuron and dorsolateral area of propodeum more or less smooth (mesopleuron also distinctly punctate). Propodeum dorsally with narrow basal longitudinal groove. Foveate groove of mesopleuron strong ( Fig. 29 ). Ovipositor somewhat shorter than body............................................................................... altamira sp. nov. 13(11) Head distinctly punctate, smooth and shining between punctures ( Fig. 26 ). Flagellum with 32–35 flagellomeres. Basal area of propodeum short and broad, weakly to strongly widened anteriorly ( Fig. 28 ). [Tergite 2 of metasoma 2.3× as long as anteriorly broad. Notaulus well developed, as rather long furrow with crest anteriorly ( Fig. 27 ). Hind leg dark brown to black with coxa and both trochanters yellow. Ovipositor sheath 3.8× as long as tergite 1.].............................. aprica sp. nov. - Head punctate or impunctate, finely granulate and dull at least on face, frons and vertex. Flagellum with 21–30 flagellomeres. Basal area of propodeum not as above—long and narrow ( Fig. 56 ) or weakly widened anteriorly and subrectangular ( Figs 44 , 52 )............................................................................................... 14 14 Notaulus with very strong and long longitudinal carina extending from anterolateral margin of mesoscutum ( Fig. 39 ). Scutellum with lateral longitudinal carinae very strong, reaching its posterior end and joining posteriorly ( Fig. 39 ). Ovipositor sheath about 3.0× as long as first tergite.......................................................... notaulator sp. nov. - Notaulus absent or represented as tubercle or weak wrinkle somewhat distant from anterolateral margin of mesoscutum. Scutellum with lateral longitudinal carinae weaker, reaching or not reaching its posterior end. Ovipositor sheath 1.0–2.3× as long as first tergite.................................................................................. 15 15 Propodeum entirely dark reddish brown to black, distinctly darker than rest of orange mesosoma ( Fig. 15 ). [Ovipositor sheath 1.2–1.4× as long as first tergite.]......................................................... propodeator sp. nov. - Propodeum orange or sometimes slightly infuscate dorsally, about same colour as rest of mesosoma................. 16 16 Clypeus entirely yellow, strongly contrasting with black face ( Figs 18 , 60 )...................................... 17 - Clypeus pale only in its lower 0.3–0.4 and black in upper part ( Figs 17, 19 ), or sometimes clypeus is entirely black....... 20 17 Propodeum with basal area very narrow, about 0.1× as broad as propodeum (measured between propodeal spiracles in dorsal view) ( Fig. 55 ). Flagellum with 28–30 flagellomeres. Ovipositor sheath twice as long as first tergite. [Scutellum with lateral longitudinal carinae short, reaching at most its midlength. Foveate groove narrow, not reaching anterior margin of mesopleuron. Distance between propodeal spiracle and pleural carina equal to 0.5–1.0× diameter of spiracle.]........ limona sp. nov. - Propodeum with basal area wider, at least 0.15 as broad as propodeum (measured between propodeal spiracles in dorsal view) (as in Fig. 44 ). Flagellum with 23–26 flagellomeres. Ovipositor sheath 1.2–1.6× as long as first tergite................ 18 18 Hind leg with coxa and both trochanters yellow, femur, tibia and tarsus black ( Fig. 63 ). Basal area of propodeum very weakly elongate, only 1.15× as long as broad ( Fig. 62 ). [Foveate groove of mesopleuron deep and broad. Distance between propodeal spiracle and pleural carina equal to 1.5× diameter of spiracle. Ovipositor sheath 1.6× as long as first tergite.]................................................................................................ nigrofemorata sp. nov. - Hind leg more or less entirely yellow, at most femur centrally brownish, tibia and tarsus slightly infuscate. Basal area of propodeum distinctly elongate, 1.6–2.2× as long as broad (as in Fig. 44 ).............................................. 19 19 Flagellum of antenna more or less filiform, with subbasal flagellomeres 1.5–1.7× as long as broad. Notaulus represented as weak tubercle. Scutellum with lateral longitudinal carinae short, reaching about its midlength. Foveate groove of mesopleuron sharp and narrow, not reaching anterior margin of mesopleuron. Propodeum with basal area moderately broad, about 0.15× as broad as propodeum (measured between propodeal spiracles in dorsal view). Distance between propodeal spiracle and pleural carina equal to 0.5–1.5× diameter of spiracle. Ovipositor sheath 1.4–1.6× as long as first tergite........ pseudoosa sp. nov. - Flagellum of antenna distinctly tapered towards apex, with subbasal flagellomeres 1.2–1.4× as long as broad. Notaulus usually represented as wrinkle. Scutellum with lateral longitudinal carinae usually longer, sometimes reaching posterior end of scutellum and joining posteriorly (although sometimes only reaching about midlength). Foveate groove of mesopleuron broad, with strong transverse wrinkles usually reaching anterior margin of mesopleuron (as in Fig. 43 ). Propodeum with basal area wider, 0.2–0.25× as broad as propodeum (measured between propodeal spiracles in dorsal view) (as in Fig. 44 ). Distance between propodeal spiracle and pleural carina equal to 1.5–2.0× diameter of spiracle. Ovipositor sheath shorter, 1.2–1.4× as long as first tergite..................................................................................... osa sp. nov. 20(16) Distance between propodeal spiracle and pleural carina equal to 1.5–2.5× diameter of spiracle. Antenna with 26–33 flagellomeres; mid and subapical flagellomeres square to slightly transverse ( Fig. 57 ). Foveate groove of mesopleuron broad and transversely wrinkled, but usually not reaching anterior margin of mesopleuron. Ovipositor sheath 1.65–2.2× as long as first tergite. Hind leg often extensively black............................................................ cartagoa sp. nov. - Distance between propodeal spiracle and pleural carina less than 1.5× diameter of spiracle. Antenna with 22–27 flagellomeres; mid and subapical flagellomeres usually elongate or square. Foveate groove of mesopleuron broad, with transverse wrinkles reaching anterior margin of mesopleuron. Ovipositor sheath 0.9–1.9× as long as first tergite. Hind leg yellowish brown with femur sometimes brown and tibia and tarsus infuscate....................................................... 21 21 Clypeus moderately broad, about 2.5× as broad as long ( Fig. 46 ). Mandible robust, rather strongly tapered basally. Second tergite 1.7–2.2× as long as broad anteriorly. Ovipositor sheath 1.4–1.9× as long as first tergite. Distance between propodeal spiracle and pleural carina equal to 1.0–1.5× diameter of spiracle............................... pseudoorosia sp. nov. - Clypeus wider, about 3.0× as broad as long ( Figs 41, 45 ). Mandible slender, weakly and evenly tapered. Second tergite 2.8– 2.9× as long as broad anteriorly. Ovipositor sheath 0.9–1.2× as long as first tergite. Distance between propodeal spiracle and pleural carina shorter than diameter of spiracle.................................................. orosia sp. nov.