JHR 96: 641-656 (2023) ee JOURNAL OF Areminrsrassen nu

doi: 10.3897/jhr.96. 109255 RESEARCH ARTICLE ) I Tymenopter a
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https://jhr.pensoft.net Thelnernaonl Scie of Hymenopiariss, RESEARCH

Two new Hoplitis species of the subgenus Hoplitis Klug,
1807 (Hymenoptera, Megachilidae) and the nesting
biology of H. astragali sp. nov. in Dagestan

Alexander V. Fateryga', Andreas Miiller??, Maxim Yu. Proshchalykin*

| ZL Vyazemsky Karadag Scientific Station, Nature Reserve of RAS, Branch of A.O. Kovalevsky Institute of
Biology of the Southern Seas of RAS, Nauki Str. 24, Kurortnoye, 298188 Feodosiya, Russia 2. ETH Zurich,

Institute of Agricultural Sciences, Biocommunication and Entomology, Schmelzbergstrasse 9/LFO, 8092
Zurich, Switzerland 3 Natural History Museum Bern, Department of Invertebrates, Bernastrasse 15, 3005
Bern, Switzerland 4 Federal Scientific Center of the East Asia Terrestrial Biodiversity, Far Eastern Branch of the
Russian Academy of Sciences, 100-let Vladivostoku Ave. 159, 690022 Vladivostok, Russia

Corresponding author: Alexander V. Fateryga (fater_84@list.ru)

Academic editor: Jack Neff | Received 9 July 2023 | Accepted 8 August 2023 | Published 15 August 2023
https://zoobank. org/FB63 186E-9043-4571-A1FE-EE27E3FA9D1D

Citation: Fateryga AV, Miiller A, Proshchalykin MYu (2023) Two new Hoplitis species of the subgenus Hoplitis
Klug, 1807 (Hymenoptera, Megachilidae) and the nesting biology of H. astragali sp. nov. in Dagestan. Journal of
Hymenoptera Research 96: 641-656. https://doi.org/10.3897/jhr.96.109255

Abstract

Hoplitis astragali sp. nov., a member of the H. monstrabilis species group, and H. dagestanica sp. nov., a
member of the H. adunca species group, are described. The former species is known from Dagestan in
Russia, Azerbaijan, and Turkmenistan, the latter only from Dagestan. Nests of H. astragali are described.
Females of this species excavated burrows in a vertical clay cliff, but sometimes chose a horizontal surface
for nest excavation, particularly at the entrance of old burrows of Xylocopa olivieri (Apidae). The nest bur-
rows of H. astragali were either sub-vertical or sub-horizontal. The nests were composed of one to three
brood cells, an empty vestibule in front of the outermost cell, and a closing plug at the nest entrance
made of moistened mud. ‘The inner surface of the cells was covered with a thin wall composed of compact
soil, most probably built by the female bee after cell excavation. The pollen loaf was very liquid and had
a spherical shape. The egg was deposited on its top. The cocoon consisted of a single thin layer, which
uniformly covered the whole inner surface of the cell. There was one generation per year. The prepupae
hibernated. Sapyga caucasica (Sapygidae) was recorded in the nests as a kleptoparasite. Both females and
males of H. astragali exclusively visited flowers of two species of the genus Astragalus (Fabaceae).

Keywords

Bionomics, Caucasus, megachilid bees, osmiine bees, Palaearctic region, taxonomy

Copyright Alexander V. Fateryga et al. This is an open access article distributed under the terms of the Creative Commons Attribution License
(CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

642 Alexander V. Fateryga et al. / Journal of Hymenoptera Research 96: 641-656 (2023)

Introduction

Hoplitis Klug, 1807 is the largest genus of the osmiine bees (Hymenoptera, Megachili-
dae, Osmiini) with 387 species described so far (Miiller 2023). It is distributed in the
Palaearctic, the Nearctic, and the Afrotropical region; a few species also occur in the
Oriental region (Michener 2007). The genus Hoplitis is especially diverse in the Palae-
arctic region, where 14 subgenera and 311 species occur (Praz et al. 2008; Ungricht et
al. 2008; Sedivy et al. 2012a; Miiller 2023). The largest subgenus of the genus Hoplitis
is Hoplitis s. str., which is confined to the Palaearctic region. It contains 91 species de-
scribed so far and a large number of still undescribed species amounting to more than
50. The subgenus comprises several species groups. Among them, the Hoplitis adunca
species group is the largest and one of the taxonomically most challenging osmiine
bee taxa due to the high morphological uniformity among its species, especially in the
female sex (Miiller 2016, 2023). Members of this species group nest either in various
pre-existing cavities (such as rock and stone crevices, hollow stems, abandoned nests of
other bees and wasps, insect burrows in wood, rarely empty snail shells) or construct
cells freely on the surface of rocks or stones, usually in depressions (Sedivy et al. 2013).
The building material used for nest construction is always mud, often combined with
small pebbles or gravel. Members of the Hoplitis annulata and the H. monstrabilis spe-
cies groups nest in self-excavated burrows in the ground and the 7. erythrogastra spe-
cies group contains kleptoparasites, which develop in nests of members of the H. an-
nulata species group (Michener 2007; Sedivy et al. 2013; Miller 2023).

The megachilid bee fauna of the Republic of Dagestan (Russia) is very poorly
known. A list of just 30 species, including one species later synonymized, was pub-
lished 150 years ago (Morawitz 1873); six of them were described as new, of which
four are currently recognized as valid species. Some recently published papers (Fateryga
2017; Fateryga et al. 2019; Pateryga and Proshchalykin 2020; Litman et al. 2021)
added 46 species increasing the total species number to 75, which is expected to be still
very far from the true number of megachilid bee species occurring in Dagestan. The
present contribution is a part of the currently ongoing study of the megachilid bees of
Dagestan. Several field expeditions were made to various districts of this republic in
2015-2022, which resulted in about 2000 newly collected specimens of Megachilidae.
The complete list of species will be published in a separate paper, while the purpose
of the present contribution is to describe two new Hoplitis species of the subgenus
Hoplitis. Since nests of one of these species were discovered, its bionomics is briefly
described in the present paper.

Material and method

The material for the present study was collected in Dagestan in 2018-2022 and
deposited in the collections of the Zoological Institute of the Russian Academy of
Sciences, Saint Petersburg, Russia [ZISP], the Federal Scientific Center of the East

Two new species of Hoplitis (Hoplitis) 643

Asia Terrestrial Biodiversity of the Far Eastern Branch of the Russian Academy of
Sciences, Vladivostok, Russia [FSCV], the Entomological Collection of ETH Zu-
rich, Switzerland [ETHZ], and the research collection of A.V. Fateryga, Feodosiya,
Russia [CAFK].

Morphological terminology and definitions for body measurements follow
Michener (2007) with the following specifications: i) the distance between lateral
ocellus and preoccipital margin was measured in top view rather than in lateral
view; ii) the diameter of an ocellus includes the ocellar border, which is often
of the same colour as the surrounding cuticle thereby differing from the usually
light colour of the central part of the ocellus; iii) the length of a segment of the
labial palpus was measured from its sclerotized base to the sclerotized base of the
subsequent segment; iv) the length of an antennal article was measured along its
lower margin, while its width corresponds to the maximal width of the article; v)
numbering of antennal articles starts from the scapus, which is antennal article 1,
and ends with the last flagellomere, which is antennal article 12 (females) or 13
(males); vi) the number of a segment belonging to a segmented body part is put
into parentheses if a character of that segment is not developed in all individuals;
thus, “terga (2)3-6 strongly shagreened” means that tergum 2 is strongly sha-
greened as terga 3-6 in some but not all specimens. Measurements to the nearest
0.1 mm or 0.5 mm (for body length) were taken using an ocular micrometer on an
Olympus VNT stereomicroscope. Photomicrographs were taken with a Keyence
VHX-2000 digital microscope.

The nesting biology of Hoplitis astragali sp. nov. was investigated 6 km northwest
of Chirkey in the Buynaksky district (43°00'10"N, 46°53'51"E) in 2022. Six nesting
females were recorded on 27 May at a clay cliff. One of them was sealing her nest
with soil; this nest was dissected immediately after the female had finished the closing
plug. The other five nests were marked with two triangular pieces of red plastic each;
the markers were inserted in an equal distance of about 10 cm from the nest entrance,
so that the latter lay in the middle between them. ‘The second visit to this place on
31 May revealed that four of the five nests still open on 27 May were sealed with soil
plugs and that an additional nest was built and sealed near one of them. All five sealed
nests were extracted from the cliff together with the surrounding earth excavated with
the help of a shovel. The earth lumps were transferred to the laboratory and the nests
were dissected in October 2022 by removing the surrounding earth layer by layer
with a knife. In total, six nests were studied, including the freshly sealed one. Plans
of the nest structure were drawn on paper and the direction of the nesting burrows
and brood cells determined with a compass. Contents of nest cells from the dissected
nests were placed into glass tubes sealed with cotton plugs and then kept under out-
door conditions. Photographs of the nests were taken with a Canon EOS RP digital
camera, a Sigma AF 105 mm f/2.8 and a Canon RF 35 mm f/1.8 macro lens, and
a Yongnuo YN-14EX macro flash. Additional observations on flower visits by both
new species of Hoplitis were made in Tsudakhar in the Levashi district (42°19'40"N,
47°09'48"E) in 2018-2022.

644 Alexander V. Fateryga et al. / Journal of Hymenoptera Research 96: 641-656 (2023)

Taxonomy

Hoplitis (Hoplitis) astragali Fateryga, Miller & Proshchalykin, sp. nov.
https://zoobank.org/69FC78C0-D4DA-473E-9538-FFCF4E52C8 10
Fig. [A-H

Type material. Holotype. Russia. Dagestan, Levashi district: Tsudakhar, 42°19'40"N,
47°09'48"E, 10.6.2019, & (leg. A. Fateryga). Deposited in ZISP.

Paratypes. Russia. Dagestan, Buynaksky district: 6 km NW _ Chirkey,
43°00'1.0"N, -46°53'5 LE, 26—27!5.2022;. 1-9, 7-¢ (leg. A. Fateryga), 7 9, 2 J
(leg. M. Proshchalykin); Dagestan, Kumtorkalinsky district: Sarykum sand dune,
43°00'08"N, 47°14'15"E, 28-29.5.2019, 8 9, 1 3 (leg. M. Proshchalykin, V. Lok-
tionov); ibid., 30.5.2019, 2 2 (leg. M. Mokrousov); Dagestan, Levashi district: Tsu-
dakhar, 42°19'40"N, 47°09'48"E, 23.6.2018, 1 3 (leg. A. Fateryga); ibid., 1.6.2019, 2
Q (leg. M. Proshchalykin, V. Loktionov), 5 J (leg. A. Fateryga); ibid., 10-11.6.2019,
12 POs eg. (leg. A. Fateryga); ibid., 16.6.2021, 1 J (leg. A. Fateryga); ibid., 28-
29.5.2022, 1 9,2 d (leg. A. Fateryga), 5 9, 15 o (leg. M. Proshchalykin); Dagestan,
Laksky district: vicinity of Turtsi, 42°11'34"N, 47°09'33"E, 22.5.2021, 4 @ (leg. A.
Fateryga). AZERBAIJAN. Nakhchivan Autonomous Republic: Babek, Sirab, 1.6.2020,
1 2 (leg. M. Maharramov). TuRKMENIsTAN: Ashgabat environs, 15.5.1993, 3 9,14
(leg. M. Halada). Deposited in ZISP, FSCV, ETHZ, and CAFK.

Diagnosis. Among the western Palaearctic Hoplitis species of the subgenus Hoplitis
s. str., the female of H. astragali (Fig. 1A) is unequivocally characterised by the fol-
lowing combination of characters: i) apical margin of sternum 6 without submarginal
carina; ii) tibial spurs of hind leg apically blunt with very short tip oriented at right
angles to the longitudinal axis of the spur (Fig. 1G); iii) clypeus medially with impunc-
tate longitudinal zone, which is usually continuous, well delimited, about 2—5x as wide
as diameter of adjacent punctures and roughly parallel-sided (Fig. 1C); iv) declivous
lateral side of apical part of labrum about as high as length of last antennal article
(Fig. 1E); v) marginal zones of terga 1-5 with long, dense and uninterrupted band of
cream-coloured hairs, which turn to white in worn specimens. The male of H. astragali
(Fig. 1B) is easily diagnosed by the following combination of characters: i) apical mar-
gin of tergum 7 medially truncate to slightly rounded (Fig. 1H); ii) gonoforceps api-
cally with finger-like projection directed inwards at right angles to its longitudinal axis
(Fig. 1H); iii) sterna (2)3—4 medially with inconspicuous, very narrow and little raised
longitudinal keel; iv) antennal articles 4-13 longer than wide and ventrally weakly
keeled (Fig. 1D); v) marginal zone of sterna 2—4 with rather dense white hair band
(Fig. 1F); vi) lobes of bilobed membranous appendage at apical margin of sternum 6
roughly quadrangular in shape and separated from each other by narrow longitudinal
zone beset with reddish-brown spines (Fig. 1F).

Assignment to species group. [he Hoplitis monstrabilis species group of Hoplitis
(Hoplitis) includes several species that are morphologically and biologically intermedi-
ate between the members of the H. adunca species group and the H. annulata species

Two new species of Hoplitis (Hoplitis) 645

Figure |. Hoplitis astragali sp. nov. A, C, E, G female B, D, F, H male A, B habitus in lateral view
C clypeus in front view D antenna in front view E mandible and labrum in lateral view F sterna 1-6 in
ventral view G part of hind leg with inner tibial spur H terga 4—7 and genitalia in dorsal view.

group (Sedivy et al. 2012b, 2013; Miiller 2023). The representatives of the H. monstra-
bilis species group differ from those of the H. adunca species group by the absence of
a submarginal carina on female sternum 6 and their habit of nesting in self-excavated

646 Alexander V. Fateryga et al. / Journal of Hymenoptera Research 96: 641-656 (2023)

burrows in the ground rather than in pre-existing cavities or stone irregularities above
ground. They differ from the 1. annulata species group by the shape of male tergum 7,
which is apically truncate to rounded rather than bidentate. In accordance with these
differences, H. astragali is assigned here to the H. monstrabilis species group.

Description. Due to the uniform morphology of the numerous species of Hoplitis
(Hoplitis), the following description is restricted to characters, which are relevant for
the recognition of the new species.

Female. Body length 7-9 mm. Head: Head 0.85—0.9x as long as wide. Distance
between lateral ocellus and preoccipital margin 2.3—2.4x as long as ocellar diameter.
Second segment of labial palpus 1.6—1.7x as long as first segment and 0.8—0.9x as
long as compound eye. Proboscis reaching coxa of fore leg when folded. Mandible
three-toothed, its preapical zone reddish. Clypeus densely punctate except for median
impunctate longitudinal zone, which is usually continuous, well delimited, maximally
4—5x as wide as diameter of adjacent punctures and roughly parallel-sided (Fig. 1C).
Apical margin of clypeus medially straight to very shallowly emarginate and weakly
crenulate. Yellowish-white pilosity at apical margin of clypeus long, its longest hairs
almost as long as maximal length of clypeus (Fig. 1C). Punctation of supraclypeal area
and frons very dense and finer than that of clypeus. Labrum basally impunctate, its
lateral sides apically strongly declivous (Fig. 1E) and about as high as length of last
antennal article. Antennal article 3 about 1.5x as long as apically wide and 1.4—1.6x as
long as article 4. Anterior side of antennal articles (4)5—10(11) partly reddish-brown.
Mesosoma: Tegula predominantly yellowish-red. Scutum and scutellum densely punc-
tured with interspaces not reaching the diameter of one puncture except medially and
laterally, where interspaces may exceed the diameter of one puncture. Basal area of pro-
podeum shagreened except for more or less extended polished zone along lower lateral
borders. Posterior surface of propodeum polished with scattered punctures. Propodeal
pit polished. Tibial spur of fore leg elongated into tip, which is slightly longer than ba-
sally wide and connected to more basal part of spur by straight to weakly concave mar-
gin. Tibial spurs of hind leg yellowish, almost parallel-sided and apically blunt with very
short tip oriented at right angles to longitudinal axis of spur; inner spur slightly longer
than outer spur and roughly 10x as long as maximally wide (Fig. 1G). Metasoma:
Punctation of tergal discs dense with interspaces reaching the diameter of one to two
punctures. Marginal zone of terga 1—5 reddish to yellowish and covered with long,
dense and uninterrupted band of cream-coloured hairs (Fig. 1A), which are medially
slightly longer than last antennal article. When seen from behind, longest erect hairs on
median half of tergum 1 more than half to almost as long as maximal length of lateral
hair tuft. Declivous lateral part of tergum 1 and marginal zone of sterna 2—5 yellowish.
Apical margin of sternum 6 without submarginal carina. Scopa white.

Male. Body length 7.5—-10 mm. Head: Head 0.84—0.87~ as long as wide. Distance
between lateral ocellus and preoccipital margin 1.7—2x as long as ocellar diameter.
Second segment of labial palpus 1.6—1.7x as long as first segment and 0.8-0.9x as
long as compound eye. Proboscis reaching coxa of fore leg when folded. Mandible
two-toothed, its preapical zone black to more or less reddish. Clypeus rather strongly

Two new species of Hoplitis (Hoplitis) 647

convex in profile, its punctation dense except sometimes for its median part, where
interspaces between punctures may be larger forming a small polished area or a non-
continuous midline. Apical margin of clypeus medially straight to very shallowly emar-
ginate and weakly crenulate. Antennal article 3 about 1.3x as long as apically wide
and articles 4-13 1.5—2x as long as wide. Ventral side of antennal articles 4-13 with
weakly delimited and rounded longitudinal keel. Ventral and anterior side of anten-
nal articles 3-13 more or less light brown to yellowish-brown (Fig. 1D). Mesosoma:
Tegula predominantly yellowish-red. Scutum and scutellum densely punctured with
interspaces hardly reaching the diameter of one puncture except medially and laterally,
where interspaces may exceed the diameter of one puncture. Basal area of propodeum
shagreened except for more or less extended polished zone along lower lateral borders.
Posterior surface of propodeum polished with scattered punctures. Propodeal pit pol-
ished. Tibial spur of fore leg elongated into tip, which is about as long as basally wide
and connected to more basal part of spur by straight to weakly concave margin. Tibial
spurs of hind leg yellowish and almost parallel-sided except for apex, which is slightly
curved. Metasoma: Punctation of tergal discs rather dense with interspaces reaching
the diameter of two to three, rarely more punctures. Marginal zone of terga 1-5 red-
dish to yellowish and covered with long, dense and usually uninterrupted whitish hair
band (Fig. 1B). Tergum 6 laterally toothed, its marginal zone yellowish and ciliated
with yellowish hairs. Apical margin of tergum 7 medially truncate to slightly rounded
(Fig. 1H). Declivous lateral part of tergum 1 and marginal zone of sterna (1)2—5 yel-
lowish. Apical margin of sternum 1 straight, of 2-4 medially shallowly emarginate and
of 5 distinctly emarginate (Fig. 1F). Marginal zone of sterna 2—4 with rather dense
white hair band (Fig. 1F). Sterna (2)3—4 medially with inconspicuous, very narrow
and little raised longitudinal keel. Sternum 5 medially with very narrow longitudinal
row of yellowish hairs directed backwards. Sternum 6 basally with pair of membranous
flaps. Lobes of bilobed membranous appendage at apical margin of sternum 6 roughly
quadrangular in shape (Fig. 1F) and separated from each other by narrow longitudinal
zone beset with reddish-brown spines. Gonoforceps slightly wider than penis valve
and apically with finger-like projection, which is directed inwards at right angles to its
longitudinal axis and about 3x as long as maximally wide (Fig. 1H).

Distribution. Mountainous Dagestan in Russia (from 75 to 1350 m a.s.l.), Nakh-
chivan Autonomous Republic of Azerbaijan, and southernmost Turkmenistan.

Etymology. The species epithet refers to the flowers of Astragalus L. (Fabaceae)

exploited by the species for pollen and nectar (see below).

Hoplitis (Hoplitis) dagestanica Fateryga, Miller & Proshchalykin, sp. nov.
https://zoobank.org/33893507-BAC4-4602-9B50-EFB4869722AF
Fig. 2A-H

Type material. Holotype. Russia. Dagestan, Levashi district: Tsudakhar, 42°19'40"N,
47°09'48"E, 11.6.2019, 4 (leg. A. Fateryga). Deposited in ZISP.

648 Alexander V. Fateryga et al. / Journal of Hymenoptera Research 96: 641-656 (2023)

Paratypes. Russia. Dagestan, Levashi district: Tsudakhar, 42°19'40"N,
47°09'48"E, 1.6.2019, 2 ¢ (leg. A. Fateryga), 3 ¢ (leg. M. Proshchalykin, V. Lok-
tionov); ibid., 10.6.2019, 2 3 (leg. A. Fateryga); ibid., 28-29.5.2022, 1 9, 1 J (leg.
A. Fateryga), 2 9, 13 d (leg. M. Proshchalykin); Dagestan, Rutul district: near Kufa
village, 6 km NW Rutul, 41.565178°N, 47.362029°E, 1500 m, 1.7.2018, 1 J (leg.
M. Proshchalykin, V. Loktionov, M. Mokrousov). Deposited in ZISP, FSCV, ETHZ,
and CAFK.

Diagnosis. Among the western Palaearctic Hoplitis species of the subgenus Hoplitis
s. str., the female of H. dagestanica (Fig. 2A) is unequivocally characterised by the fol-
lowing combination of characters: i) sternum 6 lateroapically with distinct submar-
ginal carina and medioapically not elongated into distinct and well delimited tooth of
narrowly triangular to linear shape; ii) proboscis not reaching till trochanter of hind leg
in repose and second segment of labial palpus distinctly shorter than maximal length
of mesosoma measured in lateral view (Fig. 2A); iii) clypeus and galea of proboscis
normally haired, without apically curved or wavy pollen-collecting bristles; iv) lateral
lobes of pronotum not inflated; v) apex of inner tibial spur of hind leg strongly curved
at an angle of 60 to 80 degrees (Fig. 2G); vi) clypeus medially without uninterrupted
sharp and narrow longitudinal carina; vii) disc of tergum 5 covered with rather dense
and appressed cream-coloured to yellowish-white pilosity (Fig. 2C); viii) when seen
from behind, longest erect hairs on median half of tergum 1 only about 1/7 to 1/8
as long as maximal length of lateral hair tuft (Fig. 2E); ix) punctation of lateroapical
part of scutum with interspaces reaching the diameter of one puncture; x) metasomal
scopa yellowish (Fig. 2A); xi) anterior side of antennal articles (5)6—11 partly dark red-
dish-brown. The male of H. dagestanica (Fig. 2B) is easily diagnosed by the following
combination of characters: i) apical margin of tergum 7 medially rounded (Fig. 2H);
ii) second segment of labial palpus shorter than compound eye (Fig. 2B); iii) last article
of antenna almost twice as long as basally wide and tapering towards apex with ventral
margin slightly concave (Fig. 2D, F); iv) posterior side of antenna with roundish bump
near distal end of articles (4)5—6 and small pointed tubercle near distal end of articles
7-11(12) (Fig. 2F); iv) ventral margin of antennal articles (4)5—10(11) distally slightly
widened (Fig. 2D); v) antennal article 3 1.4—1.5x as long as apically wide and longer
than article 4 (Fig. 2D); vi) lateral lobes of bilobed membranous appendage at apical
margin of sternum 6 densely haired, distinctly wider than long, laterally elongated
into a distinct and more or less acute tip and separated from each other by only a
rather shallow median emargination (Fig. 2H); vii) marginal zone of sterna 4—5 red-
dish and very densely punctured with interspaces much narrower than the diameter of
one puncture (Fig. 2H).

Assignment to species group. Due to the presence of a submarginal carina on
female sternum 6 and the apically rounded male tergum 7, H. dagestanica is clearly a
member of the H. adunca species group.

Description. Due to the uniform morphology of the numerous species of Hoplitis
(Hoplitis), the following description is restricted to characters, which are relevant for
the recognition of the new species.

Two new species of Hoplitis (Hoplitis) 649

ae
: Rig =

Figure 2. Hoplitis dagestanica sp. nov. A, C, E, G female B, D, F, H male A, B habitus in lateral view
C terga 4—6 in dorsal view D antenna in front view E terga 1-2 from behind F antenna in top view G part

of hind leg with inner tibial spur H sterna 5—6 and tergum 7 in ventral view.

Female. Body length 7-8 mm. Head: Head about 0.95x as long as wide. Distance
between lateral ocellus and preoccipital margin about 1.75x as long as ocellar diam-
eter. Second segment of labial palpus about 1.35x as long as first segment and about
0.75x as long as compound eye. Proboscis reaching coxa of fore leg when folded.
Mandible three-toothed, its preapical zone weakly reddish. Clypeus densely punctured
with interspaces rarely surpassing the diameter of half a puncture and without distinct
polished midline. Antennal article 3 almost 2x as long as apically wide and about 2x as

650 Alexander V. Fateryga et al. / Journal of Hymenoptera Research 96: 641-656 (2023)

long as article 4. Anterior side of antennal articles (5)6—11 partly dark reddish-brown.
Mesosoma: Tegula yellowish-brown except for black anterior third and black inner
margin. Scutum and scutellum densely punctured with interspaces rarely surpassing
the diameter of one and a half punctures except lateroapically on scutum and medially
on scutum and scutellum, where interspaces may reach the diameter of one puncture.
Basal area of propodeum shagreened throughout. Posterior surface of propodeum sha-
greened with scattered punctures. Propodeal pit polished. Tibial spur of fore leg elon-
gated into tip, which is slightly longer than basally wide and angularly stepped from
more basal part of spur. Tibial spurs of hind leg yellowish; inner spur slightly tapering
towards apex, which is strongly curved at an angle of 60 to 80 degrees (Fig. 2G); outer
spur slightly shorter than inner spur, its apex curved at an angle of about 45 degrees.
Metasoma: Punctation of tergal discs moderately dense with interspaces reaching the
diameter of two to three punctures on discs 1-3 (Fig. 2E). Marginal zone of terga 1-5
covered with uninterrupted band of cream-coloured to yellowish-white hairs (Fig. 2A),
which may be interrupted on tergum 1 in worn specimens (Fig. 2E). Tergal discs 1-4
with short erect pilosity of yellowish hairs, which are shorter than antennal article 2.
When seen from behind, longest erect hairs on median half of tergum 1 only about
1/7 to 1/8 as long as maximal length of lateral hair tuft (Fig. 2E). Disc of terga 5—6
covered with rather dense and appressed cream-coloured to yellowish-white pilosity.
Sternum 6 lateroapically with distinct submarginal carina and medioapically without
well delimited tooth (Fig. 2C). Scopa yellowish.

Male. Body length 7.5—9.5 mm. Head: Head about 0.85x as long as wide. Distance
between lateral ocellus and preoccipital margin about 1.75x as long as ocellar diameter.
Second segment of labial palpus about 1.35x as long as first segment and 0.75x as long
as compound eye. Proboscis reaching coxa of fore leg when folded. Mandible two-
toothed and predominantly black, sometimes with dark reddish-brown preapical zone.
Clypeus rather strongly convex in profile, its punctation very fine and dense without
polished interspaces. Apical margin of clypeus medially straight and crenulate. Anten-
nal article 1 about 2x as long as maximally wide (Fig. 2D). Antennal article 3 1.4—1.5x
as long as apically wide and almost 1.5x as long as article 4 (Fig. 2D). Posterior side
of antenna with roundish bump near distal end of articles (4)5—6 and small pointed
tubercle near distal end of articles 7-11(12) (Fig. 2F). Ventral margin of antennal
articles (4)5—10(11) distally slightly widened (Fig. 2D). Last article of antenna almost
twice as long as basally wide and tapering towards apex with ventral margin slightly
concave (Fig. 2D). Antenna predominantly yellowish-red; black to dark brown are
articles 1, 2, base of 3, apex of 13, and sometimes dorsal side of articles 3—7 (Fig. 2F).
Mesosoma: Tegula predominantly yellowish-red. Scutum and scutellum densely punc-
tured with interspaces hardly surpassing the diameter of one puncture. Basal area of
propodeum shagreened throughout. Posterior surface of propodeum shagreened with
scattered punctures. Propodeal pit polished. Tibial spur of fore leg elongated into tip,
which is slightly longer than basally wide and angularly stepped from more basal part
of spur. Tibial spur of hind legs yellowish, tapering towards apex and apically curved.
Metasoma: Punctation of tergal discs moderately dense with interspaces reaching the

Two new species of Hoplitis (Hoplitis) 651

diameter of three to four punctures on discs 1-4. Marginal zone of terga 1—5 cov-
ered with uninterrupted band of yellowish-white hairs (Fig. 2B). Tergum 6 laterally
toothed, its marginal zone reddish, ciliated with yellowish hairs, apically crenulate and
medially usually slightly emarginate. Apical margin of tergum 7 medially rounded
(Fig. 2H). Marginal zone of sterna 2—5 reddish and very densely punctured with inter-
spaces much narrower than the diameter of one puncture. Apical margin of sterna 1-4
almost straight and of 5 weakly rounded and medially shallowly emarginate. Marginal
zone of sterna 2—4 with loose whitish hair band. Sterna 2—5 with preapical transverse
swelling, which is sparsely punctured and medioapically emarginate on sterna 3—5.
Sternum 6 basally with pair of membranous flaps (Fig. 2H). Lobes of bilobed mem-
branous appendage at apical margin of sternum 6 densely haired, distinctly wider than
long, laterally elongated into a distinct and more or less acute tip and separated from
each other by only a rather shallow median emargination (Fig. 2H). Gonoforceps very
narrow, slightly bent inwards and downwards in its apical third and apically with dense
and short tuft of white hairs. Outer margin of penis valve ciliated with white bristles,
of which the longest are slightly longer than the maximal valve width.

Distribution. Mountain Dagestan in Russia (from 1120 to 1450 mazs.l.).

Etymology. The species epithet refers to the occurrence of the species in Dagestan.

Nesting biology

Six nests of Hoplitis astragali were studied 6 km northwest of Chirkey at a clay cliff
along a dry riverbed (Fig. 3A). All six nests were burrows in the ground. Two nests
were located on strongly inclined surface (Fig. 4A), while four nests were located on

almost horizontal surface at the entrance of old burrows of Xylocopa olivieri Lepeletier,
1841 (Hymenoptera: Apidae) (Fig. 4B). Thus, the main shaft of the former two nests
was sub-horizontal (Fig. 4C), while it was sub-vertical in the latter four nests (Fig. 4E,

Figure 3. Habitats of the two new species of the genus Hoplitis Klug, 1807 in Dagestan A clay cliff along
dry riverbed 6 km northwest of Chirkey, a nesting site of H. astragali sp. nov. B clay cliff along unpaved
road in Tsudakhar, the type locality of both 1. astragali and H. dagestanica sp. nov.

652 Alexander V. Fateryga et al. / Journal of Hymenoptera Research 96: 641-656 (2023)

F). The excavation process was not observed, but it was evident from the following
observation that the burrows were self-excavated by the females: two closing plugs were
observed on 31 May (Fig. 4D) at the same old X. olivieri nest entrance, where there was
just one burrow on 27 May (Fig. 4B). Thus, the second burrow was excavated by the
female bee, since there was no pre-existing hole available to her. It is noteworthy that
the nest entrances were not always circular but sometimes of irregular shape (Fig. 4B).

The nests were composed of one to three brood cells, an empty vestibule, and the
closing plug. Of the six nests studied, two had one cell, three were two-celled, and
one was three-celled (median two cells per nest). The lengths of the nest burrows were
16-32 mm (median 26 mm). The cells in two- and three-celled nests were linearly ar-
ranged in a straight burrow (n = 3, Fig. 4F) or lay in an angled burrow with the longitu-
dinal axis of the brood cells diverging at nearly right angles (n = 1, Fig. 4E). When meas-
ured on the inside, the cells were 6.5—9.5 mm long (median 8.0 mm) and maximally
5.5—-7 mm wide (median 6.0 mm). The inner surface of the cells was smooth, dull and
not covered with any substance other than mud. Although the cell construction process
was not observed, the presence of an about 0.4 mm thin and more or less distinct inner
cell wall (Fig. 4C, F) suggests that the female covered the inner surface of the cell with
an extra layer of mud. As this extra layer was of the same colour as the surrounding
substrate, the material for its construction was probably taken from inside the nest. The
material used for the construction of the cell plug was apparently also taken from inside
the nest as suggested by the irregular shape of the vestibule, indicating that soil material
had been harvested from its walls (Fig. 4C, E, F). In contrast, the closing plug was made
from soil taken from outside the nest as evidenced by the plug colour, which usually dif-
fered from the surrounding substrate (Fig. 4D). One female was observed to harvest dry
clay from the cliff surface at a distance of about 0.5 m from the nest, mixed this material
with regurgitated liquid, and transported the moistened mud to the nest entrance to
build the sealing plug (Fig. A). The space in front of the outermost brood cell was not
filled with soil resulting in an empty vestibule of 5—14 mm in length (median 7.0 mm).

The freshly sealed nest contained a single brood cell with an egg and a pollen loaf
(Fig. 4C). The pollen loaf was of orange colour and spherical shape, taking about half
of the inner volume of the cell. It was very liquid and probably kept its shape due to
surface tension and a significant amount of pollen covering it as suggested by the fact
that it immediately lost its shape during an attempt to extract it from the cell. The egg
was deposited on the top of the pollen loaf and directed with its free end towards the
cell plug; its size was about 2.7x0.8 mm. Other cells, dissected in autumn, contained
prepupae hibernating in their self-spun cocoons (Fig. 4E, F). The cocoon consisted of
a single thin layer; it was whitish and had a slightly shining inner surface. There was no
distinct area for air-exchange as known for many other osmiine bees with more com-
plex cocoon structure (Rozen and Praz 2016). Instead, the cocoon of H. astragali uni-
formly covered the whole inner surface of the cell including the inner side of the cell
plug. The larval feces were deposited between the cell wall and the cocoon, where they
were spread uniformly and sparsely. The prepupae were of deep yellow colour. There

Two new species of Hoplitis (Hoplitis) 653

Figure 4. Nesting biology of Hoplitis astragali sp. nov. A female closing her nest with a plug of mud

B female inside her nest burrow C freshly sealed one-celled nest in lateral view showing a cell with pol-
len loaf and egg D closing plugs of two nests (the right one the same as shown in B) E two-celled nest
in lateral view with hibernating prepupae F two nests (the same as in D) in lateral view with hibernating

prepupae and cocoons of Sapyga caucasica Radoszkowski, 1880. Scale bars: 1 cm.

654 Alexander V. Fateryga et al. / Journal of Hymenoptera Research 96: 641-656 (2023)

was a single generation, i.e., the progeny of the females nesting in May hibernated. Six
prepupae were obtained in 2022 and observed. Two females and two males emerged in
2023, while two prepupae remained alive but did not pupate; they obviously contin-
ued hibernation for a second winter.

Cocoons of the kleptoparasitic wasp Sapyga caucasica Radoszkowski, 1880
(Hymenoptera: Sapygidae) (Fig. 4F) were found in three of the 11 cells (27%). This
wasp hibernates as an imago allowing for its immediate identification to the species
level. Several individuals of S. caucasica were also observed in May inspecting the
surface of the clay cliff where H. astragali was nesting.

Flower associations

In Tsudakhar, both new species were observed in the vicinity of a clay cliff along an
unpaved road (Fig. 3B). Here, flower-visiting imagines were exclusively recorded on
flowers of Astragalus (Fabaceae). Two species of this genus were abundant and in flower
during the observation period: Astragalus haesitabundus Lipsky and A. onobrychioides
M. Bieb. Females and males of Hoplitis astragali as well as a single male of H. dagest-
anica were observed only on the flowers of the former species, whereas no visits to the
flowers of the latter species were recorded. In the vicinity of Chirkey A. haesitabundus
was also abundant and in flower, but here most females and males of H. astragali visited
the flowers of another Astragalus species, A. bungeanus Boiss.

Discussion

Hoplitis astragali is the sixth described species of the H. monstrabilis species group,
while 1. dagestanica is the 51* described species of the H. adunca species group (Miil-
ler 2023). Among the members of the H. monstrabilis species group, nests were already
known for H. monstrabilis Tkalci, 2000 and H. tenuiserrata (Benoist, 1950) (Rozen
et al. 2009; Sedivy et al. 2013; Le Goff 2017). The present contribution supplements
those data with the information on the nests of H. astragali. All three species excavate
their nests in the ground. The nests of H. monstrabilis and H. tenuiserrata, however,
were recorded in horizontal ground and their burrows were sub-vertical. Hoplitis as-
tragali nested in vertical cliffs but most of its nests had sub-vertical burrows due to
their location at the entrance of horizontal old burrows of Xylocopa olivieri. The nests
of H. astragali have a vestibule, i.e., the burrow between the last brood cell and the
sealing plug is not filled with soil. Whether such an empty vestibule is also present in
the nests of other members of the H. monstrabilis species group is unknown, since all
discovered nests of H. monstrabilis (n = 2) and H. tenuiserrata (n = 1) were incomplete
(Rozen et al. 2009; Le Goff 2017). As in H. astragali, the cells of H. monstrabilis and
H. tenuiserrata were also found to have a thin wall of compact soil covering the inner
cell surface. In the latter two species, it was not clear whether this wall was applied by
the female or whether it merely resulted from the smoothing of the inner surface of the

Two new species of Hoplitis (Hoplitis) 655

newly excavated cell (Rozen et al. 2009; Le Goff in Miller 2023). Our observations on
H. astragali suggest that H. monstrabilis and H. tenuiserrata also cover the inner surface
of the cell with an extra layer of mud. Lining the brood cells with an extra layer of mud
is also known from members of the Hoplitis adunca species group, such as H. adunca
(Panzer, 1798) and H. manicata (Morice, 1901) (Miller 2023 and references therein).
Trophic relationships of H. astragali appear to be typical of the H. monstrabilis
species group. Both H. monstrabilis and H. tenuiserrata are oligolectic on Fabaceae
(Rozen et al. 2009; Sedivy et al. 2012b; Miiller 2023). We observed H. astragali exclu-
sively visiting flowers of two species of Astragalus (Fabaceae), which might indicate nar-
row oligolecty on a single plant genus (Miller and Kuhlmann 2008). However, more
flower visiting data including microscopical analysis of pollen contained in the female
scopae are needed to clarify the species’ degree of host plant specialization. One male
of H. dagestanica was also observed on flowers of Astragalus. However, as this was the
only flower visiting record for this species, any assumption on its pollen host preference
is premature, although many members of the H. adunca species group exclusively or
predominantly exploit Fabaceae for pollen (Miller 2016, 2023; Sedivy et al. 2012b).

Acknowledgements

Mikhail Mokrousov (Nizhny Novgorod, Russia) kindly identified the species of Sapyga
from the nests of Hoplitis astragali. Max Kasparek (Heidelberg, Germany) and one
anonymous reviewer carefully reviewed the manuscript and provided helpful sugges-
tions to improve it. John Neff kindly improved our English.

The research was carried out within the state assignments of the Ministry of Sci-
ence and Higher Education of the Russian Federation, No. 121032300023-7 (for A.F)
and No. 121031000151-3 (for M.P).

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