Megalomya nigrolineatus, Riedel, 2019

Riedel, Matthias, 2019, Four new species of the genus Megalomya UCHIDA (Hymenoptera, Ichneumonidae, Alomyinae) Irom Laos, Linzer biologische Beiträge 51 (1), pp. 179-187 : 185-186

Megalomya nigrolineatus nov.sp. (figs 8, 12, 14, 16, 18)

T y p e m a t e r i a l: Holotype: ♀ ̎ Lao, Hua Phan Prov., Phon-Pan , Umg. Ort Ban Saleui, 20°13́30́́N 103°59́26́́E, 1350-1900 m MSL, 27.06.201 KJa, leg. C. Holzschuh & natives̎

(Linz). D e s c r i p t i o n: ♀. Body length 23 mm. Flagellum with 36 flagellomeres, stout; 1st

flagellomere 1.6x longer than wide, widest ones about 1.2x wider than long. Temples moderately and linearly narrowed behind eyes, not punctate, about 0.75x as long as eyes ( fig. 12 ). Occipital carina narrow medially, ± lamelliform laterally and ventrally. Frons strongly impressed centrally, smooth, with a strong triangular median lamella ( fig. 17 ). Face and clypeus densely punctate. Clypeus 3.3x wider than long, apical margin moderately concave. Labrum exposed, with rounded apical margin. Mandibles strongly swollen, lower teeth larger than upper ones.

Sides of pronotum largely smooth, with few fine punctures at upper margin, pronotal groove with some coarse transversal ridges in dorsal half; epomia present as a short blunt ridge between collare and pronotal groove. Mesoscutum smooth and shining, with fine scattered punctures; notauli impressed in frontal 0.45 of mesoscutum. Subtegular ridges sharp and narrow (fig. 14). Mesopleura with rather dense coarse punctures, specula smooth (fig. 14). Metapleura with dense punctures, partly rugose in ventral 1/4. Scutellum flat, longer than wide, with very scattered fine punctures and without lateral carinae. Propodeum largely smooth, with basomedian tubercle and partly distinct paramedian longitudinal rugae. Lateral longitudinal carinae present; apical transversal carina ± developed. Femora stout; fore femora 2.8x, mid femora 3.2x, and hind femora 3.9x longer than wide.

Areolet pentagonal; 2 nd recurrent vein in its distal 0.65. Nervulus strongly postfurcal (by 0.4x its length). Nervellus of hind wing intercepted at apical 0.6.

Metasoma rather slender, smooth and shining. 1 st tergite 2.2x longer than wide, with few scattered punctures. 2 nd tergite 1.35x longer than wide, 3 rd tergite 1.15x longer than wide; tergites mooth, with few fine punctures.

Color: Mainly reddish. Flagellum reddish, flagellomeres 11-17 yellowish, following distal flagellomeres infuscate. Mandibles brown. Frontal orbits yellowish. Blackish are stemmaticum, collare, two longitudinal sublateral stripes on mesoscutum, mesosternum, dorsal and apical margins of mesopleura, margins of pronotum, ventral margin of metapleura. Wings slightly infuscate, darker at frontal margin of fore wing; pterostigma black, brownish centrally.

♂ unknown.

Remark: This new taxon runs to Megalomya townesi HE, 1991 in the key of known females ( HE 1991) but differs by the completely red metasoma, densely punctate clypeus, and fine and scattered punctation on mesoscutum.

It can be differentiated from Megalomya rufator nov.sp. by slenderer and tricolored flagella, a denser punctuation of mesopleura, sharp subtegular ridges, distinct lateral

longitudinal carinae of propodeum, black coloration of stemmaticum and mesosoma and lack of yellow spots on subtegular ridges and scutellum.

The differences between Megalomya townesi HE, M. rufator nov.sp. and M. nigrolineatus nov.sp. seem to be small. It is not impossible that they represent conspecific variants of a variable species. Due to the limited material, a definite taxonomical separation will be only possible with more material and a description of all males.

Figures

Figs 11-12: Head dorsally: (11) Megalomya rufator nov.sp. ♀; (12) Megalomya nigrolineatus nov.sp. ♀. Figs 13-14: Mesopleuron: (13) Megalomya rufator nov.sp. ♀; (14) Megalomya nigrolineatus nov.sp. ♀. Figs 15-16: Propodeum dorsally: (15) Megalomya rufator nov.sp. ♀; (16) Megalomya nigrolineatus nov.sp. ♀.

Figs 17-18: Head dorsolaterally: (17) Megalomya rufator nov.sp. ♀; (18) Megalomya nigrolineatus nov.sp. ♀.