Lamachus cushmani Khalaim et Ruíz-Cancino, 2019

Khalaim, A. I., Ruíz-Cancino, E., Coronado-Blanco, J. M. & Castañeda-Vildуzola, Á., 2019, First record of the genus Lamachus Förster, 1869 (Hymenoptera: Ctenopelmatinae) from Mexico, with description of two new species, Russian Entomological Journal 28 (2), pp. 169-179 : 173-175

3. Lamachus cushmani Khalaim et Ruíz-Cancino , sp.n.

Figs 6–13 .

MATERIAL EXAMINED. Holotype: ♀ ( UAT), Mexico, Estado de Mexico (EMex), N of Toluca, El Cerrillo, Piedras Blancas, 19°24´40´´ N, 99°42´02´´ W, 2614 m, ex Neodiprion omosus on Pinus patula , 18–23.II.2017, coll. Á. Castañeda-Vildózola.

Paratypes. Mexico, Estado de Mexico (EMex), N of Toluca, El Cerrillo, Piedras Blancas, 19°24´40´´ N, 99°42´02´´ W, 2614 m, ex N. omosus on P. patula , 18–23.II.2017, coll. Á. Castañeda-Vildózola, 2 ♀♀ ( UNAM, ZISP). Same data, but 11.II.2017, 1 male ( UAT). Same data, but reared ex N. omosus on P. patula and P. hartwegii , 1.I–28.II.2018, 35 ♀♀, 35 ♂♂ (5 ♀♀, 5 ♂♂ in BMNH; 5 ♀♀, 5 ♂♂ in TAMU; 15 ♀♀, 15 ♂♂ in UAT; 5 ♀♀, 5 ♂♂ in UNAM; 5 ♀♀, 5 ♂♂ in ZISP).N of Toluca,El Cerrillo,Piedras Blancas, 19°24´32´´ N, 99°41´21´´ W, 2612 m, ex N. omosus on P. patula , 6–13.IX.2017, 10 ♀♀, 3 ♂♂ (8 ♀♀, 2 ♂♂ in UAT; 2 ♀♀, 1 ♂♂ in UNAM). Same data, but 27.IX.2017, 1 ♀, 1 ♂ ( UAT).

COMPARISON. The new species may easily be distinguished from another Mexican species, L. toluca sp.n., by the colour pattern of the body, yellow maxillary and labial palps, darker pterostigma, lacking ventrally epicnemial carina, small- er areolet in the fore wing, intercepted above middle nervellus (cu1&cu-a), and shorter first metasomal segment (in both sexes). Lamachus cushmani sp.n. differs from six other Nearctic species by colour pattern of female, i.e. orange-brown body with scarse yellow and black markings ( Figs 6 , 8–12 ), while in other species head and mesosoma are extensively black, metasoma black or reddish brown with white and/or black markings. The new species is also characterized by its almost entirely brownish yellow antennal flagellum ( Fig. 8 ), propodeum with only lateral longitudinal carina more or less developed, and hind wing with nervellus (cu1&cu- a) intercepted somewhat above its middle.

DESCRIPTION. Female (holotype). Body length 9.3 mm. Fore wing length 8.0 mm.

Head strongly rounded behind eyes in dorsal view. Inner eye orbits slightly concave at level of bases of antennae ( Fig. 9 ). Face and frons granulate, dull, with moderately dense very fine punctures. Vertex and gena shallowly granulate, dull to weakly shining, with very fine punctures. Flagellum distinctly tapered towards apex, with approximately 36 flagellomeres ( Fig. 8 ). Face 2.2 times as broad (minimum distance between eyes) as long (measured from antennal insertions to supraclypeal furrow). Clypeus ( Fig. 9 ) about 2.6 times as broad as long, clearly separated from face, convex in upper 2/ 3 and transverselly impressed in lower 1/3, with lower margin centrally weakly concave; clypeus smooth, with fine sparse setiferous punctures. Malar space 0.3–0.4 times as long as basal mandibular width. Mandible robust, weakly tapered, with fine but sharp punctures on very finely granulate background in basal half, longitudinally striate in apical half; teeth polished, upper tooth somewhat longer than the lower. Occipital carina fine, complete, mediodorsally weakly arcuate. Hypostomal carina complete, joining occipital carina above the base of the mandible at distance equal to approximately half basal mandibular width.

Mesosoma predominantly shallowly granulate, dull to weakly shining, with fine to moderately strong (on mesopleuron) punctures; upper posterior part of mesopleuron (below speculum) with weak oblique wrinkles; propodeum in posterior half virtually impunctate, granulate, partly with very weak irregular wrinkles. Pronotum without epomia. Notaulus rather sharp, not especially deep, with anterior end well above lateral margin of mesoscutum. Scutellum with lateral longitudinal carinae present only at its extreme base. Epicnemial carina present laterally and completely absent ventrally, its upper ends extending somewhat above the level of the lower corner of pronotum, not reaching front margin of mesopleuron. Speculum smooth. Submetapleural carina complete, strong. Propodeum without carinae except for lateral longitudinal carinae which are more or less developed from posterior end of propodeum to level of propodeal spiracle. Pleural carina present, distinct. Propodeal spiracle round, separated from pleural carina by 0.5–1.0 times diameter of spiracle. Tarsal claws simple. Fore wing with areolet oblique, subtriangular, stalked above, receiving vein 2m-cu slightly before its distal corner. Hind wing with nervellus (cu1&cu-a) intercepted somewhat above its middle.

Metasomal tergites shallowly granulate, weakly polished, with very fine punctures. First tergite in dorsal view 1.6 times as long as posteriorly broad, with spiracles near its centre; lateromedian longitudinal carinae present only at extreme base of tergite; lateral longitudinal carinae present as sharp ridges at posterior end of tergite; glymmae superficial. Ovipositor short, projecting beyond subgenital plate, shorter than apical depth of metasoma ( Fig. 10 ).

Colour pattern. Head predominantly orange-brown; clypeus, face, frontal orbits and lower part of gena yellow; face with median longitudinal brown stripe in upper part ( Fig. 9 ). Mandible yellow with blackish teeth. Maxillary and labial palps yellow. Antenna with scape yellow-brown, yellowish ventrally; pedicel yellow-brown with fuscous markings; flagellum brownish yellow with two basal flagellomeres black or extensively marked with dark brown or black (sometimes flagellomere 3 also darkened dorsally), and 2 to 7 distal flagellomeres darkened with brown.

Mesosoma orange-brown with black and yellow markings. Prosternum (in ventral view, clearly discernible between propleuron and fore coxae) black; propleuron yellow in lower 0.8 and black in upper 0.2; pronotum with broad yellow band on front margin, broad black band centrally (parallel to front margin), and orange-brown in upper posterior part; with faint yellow mark on dorsolateral margin and posterior corner yellow. Mesoscutum orange-brown, with a pair of large yellow marks anterolaterally; prescutellar concavity blackish. Scutellum and postscutellum yellow on median concavities, laterally orange-brown. Mesopleuron orange-brown with subtegular ridge and ventro-lateral mark (on path of epicnemial carina) yellow, and with slight yellowish marks in front upper part and near posterior lower end; mesepimeron pale yellow; impression in upper part of mesopleuron between subtegular ridge and upper end of mesepimeron (and also narrowly above subtegular ridge) black ( Fig. 11 ). Metapleuron orange-brown, black-marked in lower part. Propodeum almost entirely orange-brown, with extreme hind margin black.

Wings almost hyaline, very weakly infumate. Pterostigma brownish black to black. Fore and mid legs with coxae and trochanters yellow, sometimes reddish basally and/or dorsally; femora, tibiae and tarsi reddish yellow, femora and tibiae more or less yellowish on front and/or dorsal sides, tibiae sometimes also yellowish basally. Hind leg with coxa, trochanters and femur reddish brown, femur darkened at extreme apical end; tibia yellow in basal 0.5–0.6 and black in apical 0.4–0.5, sometimes also darkened at extreme base; tarsus black basally to dark reddish brown apically.

Metasoma orange-brown, ventrally paler; first tergite black at base; tergites 3 and 4 (and less distinctly tergites 2, 5 and 6) mediodorsally narrowly yellow-marked on hind margin. Ovipositor sheath black, brownish at extreme apex.

Male. Morphologically similar to female; flagellum without tyloids; first tergite in dorsal view about 1.9 times as long as posteriorly broad. Colour pattern generally resembles that of female but with orange-brown colour of body and legs replaced by black ( Fig. 13 ); hind tibia with narrow black band at base; metasoma with first tergite dark reddish brown to black, following tergites predominantly reddish brown, and distal end of metasoma blackish. Antenna black, sometimes scape and pedicel yellow ventrally.

REMARKS. Colouration of alive females in nature ( Fig. 6 ) differs from those of dry specimens, mounted after their preservation in alcohol ( Fig. 10 ), i.e. dry females have body darker and more orange-brown rather than red.

The species is characterized by the considerable sexual dimorphism (see Figs 6–7 ). Females are with body almost entirely orange-brown, while in males head and mesosoma are predominantly black with yellow markings, and colouration of the metasoma varying from reddish brown to almost black, with ventral part yellowish or pale brown.

ETYMOLOGY. The species name is dedicated to Robert Asa Cushman (1880–1957), an American entomologist, expert in Hymenoptera , in recognition of his contribution to the study of North American Ichneumonidae .

DISTRIBUTION. Central Mexico (EMex).

BIOLOGY. The adult parasitoids ( Figs 6–7 ) were reared from cocoons of Neodiprion omosus Smith ( Fig. 3 ) whose larvae develop on Pinus patula Schiede and P. hartwegii Lindley ( Pinaceae ) ( Figs 1–2 ) in Central Mexico.

Figures

Figs 6–7. Lamachus cushmani sp.n. in nature: 6 — female; 7 — male. Рис. 6–7. Lamachus cushmani sp.n. в природе: 6 — самка; 7 — самец.

Figs 8–12. Lamachus cushmani sp.n., female: 8 — head with antennae, lateral view; 9 — head, front view; 10 — body, lateral view; 11 — head, mesosoma and base of metasoma, lateral view; 12 — propodeum and base of metasoma, dorsolateral view. Рис. 8–12. Lamachus cushmani sp.n., самка: 8 — голова с антеннами, сбоку; 9 — голова, спереди; 10 — тело, сбоку; 11 — голова, меЗосома и основание метасомы, сбоку; 12 — проподеум и основание метасомы, сверху и сбоку.

Fig. 13. Lamachus cushmani sp.n., male, habitus, lateral view. Рис. 13. Lamachus cushmani sp.n., самец, габитус, сбоку.

Figs 1–5. Neodiprion omosus in nature: 1–2 — feeding larvae; 3 — cocoons; 4–5 — adult sawfly. Рис. 1–5. Neodiprion omosus в природе: 1–2 — питаюЩиесЯ личинки; 3 — коконы; 4–5 — вЗрослые пилильЩики.