Crossocerus (Crossocerus) strangulatus ( Bischoff, 1930 )

Mokrousov, M. V. & Proshchalykin, M. Yu., 2023, New records of digger wasps (Hymenoptera: Crabronidae) from Altai, with taxonomical notes on Crossocerus mongolensis Tsuneki, 1972, stat. n., Russian Entomological Journal 32 (4), pp. 410-415 : 411-412

Crossocerus (Crossocerus) strangulatus ( Bischoff, 1930)

Figs 1–4 .

Crabro strangulatus Bischoff, 1930: 220 , ♀, ♂.

MATERIAL. RUSSIA: 1♂, Altai Rep., 15 km SE Kurai, Chuya River , 1600 m, 50°11.163'N 088°07.067'E, 5.VII.2016 ( VL, MP) [MMC] .

DISTRIBUTION. * Russia (Altai), Kazakhstan, Uzbekistan, Tajikistan, Kyrgyzstan, Mongolia, Northwestern China, Northern India.

NOTE. Males of Crossocerus strangulatus differ from all other species by having a deep depression behind the eyes ( Fig. 1 ). In addition, like C. bispinosus de Beaumont, 1967 and C. kohli (Bischoff, 1921) , males of this species have a characteristic feature – the presence of a spine-like base formed by glued hairs in the anteroventral part of the mesopleura ( Fig. 2 ). Males of C. strangulatus also differ from these two species in having a black flattened forebasitarsus ( Fig. 4 ) and flattened flagellomeres 1–3, antenna with long setae ( Fig. 3 ), F1 elongate, ratio L/W near 2.2×.

Females of C. strangulatus differ from other species of the subgenus in the following feature complex: precoxal tubercle of mesopleura well developed; mesoscutum in front of mesopostnotum with fine but noticeable longitudinal wrinkles; F1 ratio L/W near 3×, clypeus anteriorly tridentate; metapostnotum smooth, without oblique wrinkles. They differ from C. kohli by shape of the clypeus (central anterior lobe almost straight in C. kohli ), the long F1 (ratio L/W near 2× in C. kohli ) and the sculpture of the metapostnotum (gently entirely wrinkled at C. kohli ). To clarify the diagnosis of C. kohli , it should be noted that in this species the precoxal tubercle is sometimes clearly visible, and the mesoscutum in front of mesopostnotum is sometimes marked by very short, faint wrinkles.

Crossocerus mongolensis Crossocerus yasumatsui

Females

Lateral corners of pronotal collar slightly elevated ( Fig. 5 ) Lateral corners of pronotal collar distinctly elevated ( Fig. 6 )

Pronotal collar in frontal view (back view) slightly Pronotal collar in frontal view (back view) concave ( Fig. 8 ) uniformly convex ( Fig. 7 )

Sculpture of metapostnotum and propodeum smoother ( Fig. 9 ) Sculpture of metapostnotum and propodeum more developed

( Fig. 10 )

Pygidial area slightly convex at base ( Fig. 11 ) Pygidial area completely flat ( Fig. 12 )

Body size: 6.8–7.0 mm Body size: 7.1–7.3 mm

Males

Lateral corners of pronotal collar lower ( Fig. 13 ) Lateral corners of pronotal collar higher ( Fig. 14 )

Forefemur distinctly concave ventrally, limited by sharp Forefemur ventrally flattened at base, not limited by sharp folds folds, with lobate-like protrusion along the anterior edge at ( Fig. 16 ) the base ( Fig. 15 )

Foretrochanter angulate ( Fig. 17 ) Foretrochanter not angulate ( Fig. 18 )

Sculpture of metapostnotum and propodeum smoother (see Sculpture of metapostnotum and propodeum more developed Fig. 9 ) (see Fig. 10 )

Genae near mandibular base black or brownish, postgenae Genae yellow near mandibular base, postgenae ventrally yellow ventrally with yellow spot

Body size: 7.0– 7.7 mm Body size: 7.2–7.9 mm

Figures

Figs 1–4. Male of Crossocerus strangulatus (Bischoff, 1930): 1 — head, dorsal view; 2 — mesosoma, lateral view; 3 — antenna; 4 — foretarsus. Рис. 1–4. Самец Crossocerus strangulatus (Bischoff, 1930): 1 — голова, вид сверху; 2 — меЗосома, вид сбоку; 3 — антенна; 4 — переднЯЯ лапка.

Figs 5–12. Females of Crossocerus mongolensis Tsuneki, 1972 (5, 7, 9, 11) from Altai and C. yasumatsui (Tsuneki, 1947) from Kunashir Island (6, 8, 10, 12): 5, 6 — pronotal collar, lateral view; 7, 8 — pronotal collar, back view; 9, 10 — metapostnotum and propodeum, dorsolateral view; 11, 12 — pygidial area, dorsolateral view. Рис. 5–12. Самки Crossocerus mongolensis Tsuneki, 1972 иЗ АлтаЯ (5, 7, 9, 11) и C. yasumatsui (Tsuneki, 1947) с о. Кунашир (6, 8, 10, 12): 5, 6 — воротничок переднеспинки, вид сбоку; 7, 8 — воротничок переднеспинки, вид сЗади; 9, 10 — метапостнотум и проподеум, вид сверху и сбоку; 11, 12 — пигидиальное поле, вид сверху и сбоку.

Figs 13–18. Males of Crossocerus mongolensis Tsuneki, 1972 from Altai (13, 15, 17) and C. yasumatsui (Tsuneki, 1947) from Kunashir Island (14, 16, 18): 13, 14 — pronotal collar, lateral view; 15, 16 — foretrochanter and forefemur, ventral view; 17, 18 — foretrochanter and base of forefemur, back view. Рис. 13–18. Самцы Crossocerus mongolensis Tsuneki, 1972 иЗ АлтаЯ (13, 15, 17) и C. yasumatsui (Tsuneki, 1947) с о. Кунашир (14, 16, 18): 13, 14 — воротничок переднеспинки, вид сбоку; 15, 16 — вертлуг и бедро передних ног, вид сниЗу; 17, 18 — вертлуг и основание бедра передних ног, вид сЗади.