Hylaeus
Creators: name: Yu, Maxim
name: Dathe, Holger H.
Publisher: name: Zenodo
Year: 2012
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Colletidae
Hylaeus

description: Key to the Hylaeus species of the Asian part of Russia
Males
(males of H. montivagus Dathe and H. telmenicus Dathe unknown)
1 Supraclypeal area entirely black, also the rest of the pale mask often reduced..................................... 2
- Supraclypeal area at least basally pale spotted, mask complete................................................. 6
2 Scape black, slender, hardly broadened or bent.............................................................. 3
- Scape with at least a light stripe, more or less broadened...................................................... 4
3 Paraocular spots present (Fig. 7 g); mesopleura punctured and chagrined, with silky sheen...... H. gracilicornis (Morawitz)
- Paraocular spots missing, face black except clypeus (Fig. 9 e); mesopleura punctured, interspaces polished, glossy................................................................................................. H. niger Bridwell
4 Clypeus with a yellow spot only (Fig. 10 i); mesopleura remarkably coarsely punctured, with punctures much larger than on the mesonotum; propodeal enclosure with sharp transverse ribs................................ H. transversalis Cockerell
- Clypeus entirely yellow; mesopleura punctured almost the same as mesonotum; propodeal enclosure with wrinkled mesh ... 5
5 Scape distinctly broadened, inside deeply hollowed out; clypeus polished, only apically with scattered punctures (Fig. 9 a); larger species, body length 6.5–7.5 mm................................................ H. difformis (Eversmann)
- Scape slightly broadened, inside only shallowly hollowed out; clypeus punctured also on the interior (Fig. 9 c); smaller species, body length 5.5 mm............................................................... H. nigrocuneatus Cockerell
6(1) Scape distinctly broadened, 1.3 to 1.8 times wider than long, shield-like.......................................... 7
- Scape simple or broadened, but not wider than long.......................................................... 9
7 Scape conspicuously broadened, 1.6 to 1.8 times wider than long; T1 with satin gloss or dull......................... 8
- Scape only up to 1.3 times wider than long; mandibles black (Fig. 8 e); T1 with finely dispersed punctures, shiny............................................................................................. H. pfankuchi (Alfken)
8 Scape about one and a half times as wide as long; flagellum yellow, brownish above (Fig. 8 a); mandibles and pronotum often yellow spotted; T1 densely punctured and chagrined, mat....................................... H. dilatatus (Kirby)
- S cape nearly twice as wide as long; middle flagellomeres with dark apices, so flagellum appears ringed (Fig. 8 c); mandibles and pronotum black; T1 punctured and finely chagrined, with silky gloss................................ H. rinki (Gorski)
9 Axillae white; even mandibles, labrum and pronotum white marked; supraclypeal area impressed, clypeus arched (Fig. 11 e); sterna with four protuberances........................................................ H. variegatus (Fabricius)
- Axillae black, and features differently combined........................................................... 10
10 Sterna with metasomal protuberances or callosity........................................................... 11
- Sterna flat.......................................................................................... 15
11 S3 with strong triangular hump; S4 arched; scape cylindric thickened, black; mask white with enamel gloss (Fig. 7 a)......................................................................................... H. nigritus (Fabricius)
- Sterna partly with callosities............................................................................ 12
12 Antennae inserted close together, the distance of antennal sockets from each other less than to the orbits; scape black (Fig. 5 a); genae long, about the width of the flagellum; pronotum black................................... H. aborigensis Dathe
- Antennae inserted at a normal distance, antennal sockets about as far apart from each other as to the orbits; scape laterally with yellow stripe; genae short, narrower than width of flagellum; pronotum pale marked.............................. 13
13 Head in frontal view of transversely trapezoidal outline; mask polished, shiny (Fig. 11 c); T1 strongly chagrined and coarsely punctate............................................................................ H. signatus (Panzer)
- Head in frontal view of elongate trapezoidal outline; mask chagrined, mat; T1 very finely chagrined with only scattered, fine punctures........................................................................................... 14
14 Occiput with distinct surrounding carina; supraantennal unpunctated area distinctly larger than antennal socket........................................................................................... H. incongruus Förster 1871
- Occiput rounded, without surrounding carina; supraantennal unpunctated area nearly of the size of antennal socket (Fig. 11 a)................................................................................... H. confusus Nylander
15(10) Apical margin of S6 with V-shaped incision or emargination.................................................. 16
- Apical margin of S6 weakly convex, curved............................................................... 18
16 Mesopleura very roughly wrinkled punctate, intervals as narrow ridges; mask yellow (Fig. 10 a); incision of S6 deep V-shaped; pronotum black....................................................................... H. pectoralis Förster
- Mesopleura more or less coarsely punctured, but intervals distinctly recognizable and its surface evenly convex......... 17
17 Basal area of propodeum strongly and extensively wrinkled, distinct even on posterior area; scape enlarged, around 1.6 times longer than apically wide (Fig. 10 g)...................................................... H. noomen Hirashima
- Basal area of propodeum only wrinkled on basal part, posterior area nearly free of wrinkles; scape inconspicuous, conical..................................................................................................... 18
18 Basal area of propodeum with short longitudinal wrinkles; supraclypeal area in the upper part distinctly narrowed, parallel- sided (Fig. 10 e)....................................................................... H. globulus (Vachal)
- Basal area of propodeum with a few long transverse wrinkles; supraclypeal area in the upper part triangular (Fig. 10 c)............................................................................................ H. floralis (Smith)
19 Mesopleura with larger punctures, intervals as large as half to full puncture diameter, shiny; mask white; T1 smooth with fine, apically dense punctures; head as in Fig. 5 g.......................................... H. leptocephalus (Morawitz)
- Mesopleura with normal punctures...................................................................... 20
20 Scape hardly expanded, short or narrow conical or cylindrical................................................. 21
- Scape widened or produced, apically at least twice as wide as at its base......................................... 23
21 Propodeum rounded, with fine sculpture; T1 chagrined, with subtle but distinct punctation; head as in Fig. 7 i.................................................................................................... H. paulus Bridwell
- Propodeum with coarse wrinkles; T1 polished, without punctation.............................................. 22
22 T1 smooth, distinctly punctured; frons chagrined, silkily shiny; paraocular spots constricted on top near orbits, so that the spots appear knob-like (Fig. 5 e)............................................................ H. angustatus (Schenck)
- T1 polished, without punctures; frons above the antennal sockets with round, smooth, shiny areas; paraocular spots truncated across the top, without knob formation (Fig. 9 g)........................................... H. concinnus Cockerell
23 Scape enlarged to heart-shape.......................................................................... 24
- Scape conically enlarged............................................................................... 26
24 T1 distinctly chagrined, with flat punctures, silkily shiny; clypeus with long pale bristles, especially at the anterior margin (Fig. 6 a).............................................................................. H. annulatus (Linnaeus)
- T1 smooth, at most finely striate, shiny; clypeus without long bristles at the anterior margin......................... 25
25 T1 finely striate, with flat scattered punctures; scape apically almost as wide as long; mask lemon yellow; frons without bristle fields (Fig. 6 c).................................................................. H. cardioscapus Cockerell
- T1 polished, with dense, strong punctation; scape apically only about one and a half times as wide as long; mask ivory-white; frons with two oval bristle fields (Fig. 5 c)..................................................... H. altaicus Dathe
26 Scape short conical, just as long as the first three antenna segments together; posterior area of propodeum surrounded by sharp edge............................................................................................. 27
- Scape elongated, considerably longer than the first three antenna segments together; posterior area of propodeum without surrounding sharp carinae................................................................................ 28
27 T1 distinctly punctate, particularly apically with dense punctures; pronotum yellow marked; head as in Fig. 6 g................................................................................................ H. sibiricus (Strand)
- T1 only with scarce and very dispersed punctures; pronotum mostly black; head as in Fig. 6 e....... H. communis Nylander
28 Head in frontal view conspicuously prolonged, especially in the lower part narrowed; clypeus longer than the supraclypeal area; sides of the supraclypeal area approximately parallel; mask white, finely longitudinally striated, punctation hardly recognizable (Fig. 5 i); T1 with white side fringes.......................................... H. dolichocephalus Morawitz
- Face shorter; clypeus about as long as the supraclypeal area; sides of the supraclypeal area downwards divergent; mask ivorywhite, chagrined, with few shallow punctures (Fig. 7 c); T1 without side fringes................. H. pallescens Cockerell
description: Published as part of Yu, Maxim & Dathe, Holger H., 2012, The bees of the genus Hylaeus Fabricius 1793 of the Asian part of Russia, with a key to species (Hymenoptera: Apoidea: Colletidae), pp. 1-36 in Zootaxa 3401 on pages 28-30, DOI: 10.5281/zenodo.208438