♀:
1. Body black, at most metasoma with light colored pattern.
2. Antennae 16-segmented. Abdominal apex without aperture—females.
4. Head usually not broadened behind eyes; if, occasionally, somewhat broadened, then antennae less thin, with shorter apical segments and metasoma rounded toward apex (as much as or almost as much as toward its base) with posterior margin somewhat curved forward.
8. Head of usual shape, not projecting laterally and angularly beyond genae; temples usually not, or only slightly, rarely 2 times as long as eye. Occiput very slightly excavate. metasoma at apex without tubercle.
34. metasoma uniformly rounded in posterior part, apically somewhat curved on lower side.
38. Palpi much shorter [not longer than height of head]; proboscis slightly developed, not projecting or slightly projected.
40. Radial cell significantly longer [not extremely short].
42. Posterior margin of abdominal shield much less curved [than 1/3rd of metasoma].

44. metasoma with longitudinal rugae, usually not extending beyond its middle (not extending beyond middle, if rugae coarse). If rugae distinctly extending beyond mid-metasoma, then antennae thin with long segments or body smaller.
45. metasoma 2—2.5 times as long as wide in middle.
47. Body with less uniform though with less coarse and nonalveolar sculpture on head and major part of mesonotum. Apex of metasoma without emargination on lower side 48. Segments in apical part of antennae square or slightly longer than wide.
50. metasoma without denticulate projection at apex.
51. Body relatively large, 2.5—4.
52. metasoma broadened toward apex (Fig. 191: 7), with yellow spot at base, rarely entirely black. Basal segment of antennae, palpi, sometimes hind femora yellowish brown, rarely dark colored. Head roundly narrowed behind eyes, temples as long as eye.

53. metasoma slightly longer than wide. Yellow spot at base of metasoma fainter, sometimes not developed; basal segment of antennae reddish or black, hind femora black. Antennal segments in apical part not depressed. Head and mesosoma as in male (aperture at abdominal apex in male small, oval). Kola Peninsula, Central Urals…M. ripaeus Tobias, sp. n.

Holotype: Female, Il’men Forest Reserve, 17.VII.1958 (Tobias). Para types: Same place, 1 female, 14. VII; 9 females, 17. VII, 3 females, 1 male, 20.VII.1958 (Tobias). One male, village Khibiny, 9.VI1I.1928 (Cheburova).

♂:
129. Antennae more than 16-segmented. metasoma with aperture at apex—males.
165. Aperture on apex of metasoma much smaller, occupies not more than half abdominal width.
169. Temples much shorter [than 2 times as long as eye], not projecting angularly. Occiput significantly less emarginate [not very deeply].
181. Aperture on apex of metasoma much larger, oval [not extremely small, punctiform].
187. Body size half or less than half [than 4 - 6]. Antennae with fewer segments [than 25].
191. Head roundly narrowed behind eyes, sometimes slightly broadened, but its maximum width behind eyes not greater than in ocular region.
193. Basal segment of antennae compressed slightly [not distinctly, almost flat].
195. Hind femora black
197. Aperture on apex of metasoma black, its height 2/5 height of metasoma in apical part.
203. Anterior margin of radial cell as long as stigma or slightly shorter.
204. metasoma 2—2.5 times as long as wide. Width of aperture on apex of metasoma 2—3 times its height.
208. Body large [ > 2 - 2.5], sculpture of body coarser, with distinct wrinkles.
209. Head behind eyes slightly roundly narrowed (Fig. 196: 21, 22). Hind femora 3.5—4 times as long as wide 210. Frons quite uniformly, densely rugose-punctate. mesosoma slightly, at most 1.3 times as long as high.

212. Mesonotum without distinct transverse wrinkles. Temples 1.5 times as long as eye. Genae 1/3 as high as longitudinal diameter of eye. Face 1/2 as high as its width (Fig. 196: 22, 23). Body 3.1—3.5 … M. ripaeus Tobias, sp. n.