Ancistrocerus nigricornis ♀︎

Last update: 26 October 2021
SPECIES: Ancistrocerus nigricornis
GENUS: ANCISTROCERUS (Potter wasps)
FAMILY: VESPIDAE



OBSERVATION:
2021-X-272021-VII-222021-VI-102020-VIII-202020-VI-192020-V-202020-IX-062020-IX-052020-IV-212020-IV-202020-IV-192020-IV-052019-IX-152016-V-082016-V-06

YEARS:
2016201920202021

MONTHS:
JanFebMarAprMayJunJulAugSepOctNovDec


Ancistrocerus nigricornis ♀︎, transporting mud

1. DISTRIBUTION

A. nigricornis is an uncommon wasp [2] that can be found throughout the Netherlands [2, 4].

2. BEHAVIOUR

2.1. ACTIVITY

The species is active from March to end of September [2].

The females are the only Ancistrocerus wasps that overwinter and are active early in the year starting in March before the other species are active  in May [5]. This makes them easy to identify during that period. the males die after mating in the autumn [5]. the females have mated last summer and are already ready to lay eggs [6].
As of June the new generation emerges.

2.2. DEVELOPMENT

A. nigricornis catches larvae of Leafroller moths (Tortricidae) [4,6].

Ancistrocerus nigricornis ♀︎, with prey

They nest in all kinds of bore holes, natural or artificial. In my bee hotels they are interested in nesting holes with a diameter of ±5 mm which is in compliance with the literature that states holes with a diameter of 4 – 5 mm [5].

The females are regular guests on the bee hotels, see also here.

3. BROOD PARASITES

The following nest parasites of A. nigricornis present in the Netherlands are mentioned in the literature:

Hymenoptera
(Wasps)

Chrysididae (Goudwespen)
Chrysis (Tandgoudwespen)
Chrysis ignita [4]
Diptera
(Flies)

Sarcophagidae
Amobia
Amobia signata [15]

The following species  have been observed in the garden:


Hymenoptera
(Wasps)

Chrysididae (Cuckoo wasps)
Chrysis
Ruby-tailed wasp (Chrysis ignita) [4]

4. IDENTIFICATION

Length male 7,5 – 10,5 mm, length female 10 – 13 mm.

Females

Ancistrocerus nigricornis ♀︎

1. Legs yellow with black [3]

Ancistrocerus nigricornis ♀︎, legs yellow with black

2. Propodeum black [3]

Ancistrocerus nigricornis ♀︎, propodeum black
Ancistrocerus nigricornis ♀︎, propodeum black

3. Sternite 2 edge makes angle of ±90 degrees seen from the side, and flatly impressed behind it [3]

Ancistrocerus nigricornis ♀︎, edge sternite 2 straight angled, flat afterwards
Ancistrocerus nigricornis ♀︎, edge sternite 2 straight angled, followed by flat indentation

4. Tergite 1 normally with distinct marking [3]

Ancistrocerus nigricornis ♀︎, tergite 1 with characteristic yellow markings
Ancistrocerus nigricornis ♀︎, tergite 1 with characteristic yellow markings

5. Antenna scape underside yellow over entire length [3]

Ancistrocerus nigricornis ♀︎, antenna scape underside yellow

References

1 Nederlands Soortenregister

2 Waarneming.nl

3 SCHMID-EGGER, C. H. Bestimmungsschlüssel für die deutschen Arten der solitären Faltenwespen (Hymenoptera: Eumeninae). Deutscher Jugendbund für Naturbeobachtung, 1994, 54: 90.

4 Martynova, Kate & Fateryga, Alexander. (2015). Chrysidid wasps (Hymenoptera, Chrysididae)—Parasites of eumenine wasps (Hymenoptera, Vespidae: Eumeninae) in Crimea. Entomological Review. 95. 472-485. 10.1134/S0013873815040090.

5 Breugel, P. van 2014. Gasten van bijenhotels. – EIS Kenniscentrum Insecten en andere ongewervelden & Naturalis Biodiversity Center, Leiden.

6 Peeters, T.M.J., C. van Achterberg, W.R.B. Heitmans, W.F. Klein, V. Lefeber, A.J. van Loon, A.A. Mabelis, H. Nieuwen-huijsen, M. Reemer, J. de Rond, J. Smit, H.H.W. Velthuis, 2004. De wespen en mieren van Nederland (Hymenoptera: Aculeata). – Nederlandse Fauna 6. Nationaal Natuurhistorisch Museum Naturalis, Leiden, knnv Uitgeverij, Utrecht & European Invertebrate Survey – Nederland, Leiden.

7 POVOLNY, D. The flesh-flies of Central Europe (Insecta, Diptera, Sarcophagidae). Spixiana supplement, 1997, 24: 1-260.