Officil name:
Synonyms:

CONTENTS
1. Distribution
2. Behaviour
3. Plant relations
4. Prey relations
5. Parasitic relations
6. Identification
1. DISTRIBUTION
Agenioideus sericeus is a very rare wasp in the Netherlands and occurs especially in the southern parts [Waarneming.nl],[Peeters et al. 2004],[Nieuwenhuijsen 2008].
Garden species
Since the first observation in 2019 the species is a permanent resident in our garden.
2. BEHAVIOUR
2.1. ACTIVITY
The species is active from end May to September [Peeters et al. 2004]. Possibly bivoltine [Peeters et al. 2004].
2.2. DEVELOPMENT
Nest
The species nests in sandy slopes and in mortar joints in old walls [Peeters et al. 2004],7]. The nest consists of one or a few brood cells [7]. Observations indicate the wasp can start nest building both before and after prey capture [7].
2.3. HUNTING
A captured prey is moved across the ground to the nest either sideways or backwards by the middle legs [7]. The spider is pulled by the spinner into the nest [7].
3. PLANT RELATIONS
3.1. FOOD PLANTS
The following plant species are mentioned in literature as food sources:
Apiaceae (Umbellifers) | – |
Garden species
The garden provides some of these food plants but I have not observed the species on it yet.
Apiaceae (Umbellifers) | Foeniculum – Foeniculum vulgare (Fennel) Pastinaca – Pastinaca sativa (Parsnip) |
4. PREY RELATIONS
The species uses spiders for her brood [Peeters et al. 2004],[Nieuwenhuijsen 2008],6,7].
The following species and groups occurring in the Netherlands [Soortenregister] are mentioned in literature:
Araneidae [7] (Orbweavers) | Araneus – Araneus diadematus (Garden spider) [6,7] Zygiella – Zygiella x-notata [6] |
Thomisidae [7] (Crab spiders) | |
Linyphiidae [7] (Money spiders) | Linyphia – Linyphia triangularis [7] |
Salticidae [7] (Jumping spiders) | |
Tetragnathidae | Meta [7] |
Garden species
In an own observation a wasp transported a captured spider Zygiella x-notata, see here.
Araneidae (Orbweavers) | Zygiella – Zygiella x-notata |
5. PARASITIC RELATIONS
I have not been able to find literature references on parasites of the species.
6. IDENTIFICATION
Length males: 4,5 – 6 mm
Length females: 6 – 7,5 mm
Genus
The genus Agenioideus can be identified using the following characters:

specimen caught for photo identification on 21-viii-2021, length ±8mm



- Antenna with 12 segments [Nieuwenhuijsen 2008]
2. Abdomen with 6 segments [Nieuwenhuijsen 2008]
3. Tergite 6 with pygidium [Nieuwenhuijsen 2008]
HEAD
1. Clypeus: ventral edge trapezoidal [Nieuwenhuijsen 2008],[Notton 2018]
2. Clypeus: black [Nieuwenhuijsen 2008]
THORAX
1. Propodeum: surface smooth and covered in white down [Nieuwenhuijsen 2008]
2. Legs: all legs black [Nieuwenhuijsen 2008]
ABDOMEN
1. Tergite 2 black [Nieuwenhuijsen 2008]

1. Antenna with 13 segments [Nieuwenhuijsen 2008]
2. Abdomen with 7 segments [Nieuwenhuijsen 2008]
3. Tergite 6 without pygidium [Nieuwenhuijsen 2008]
HEAD
1. Clypeus: ventral edge trapezoidal [Nieuwenhuijsen 2008]
THORAX
1. Hind leg: shin is dark (a species variant exists with light spot proximally on the shins) [Nieuwenhuijsen 2008]
ABDOMEN
1. Tergite: rostral part tergite 2 dark [Nieuwenhuijsen 2008]
2. Sternite: subgenital plate seen sideways flat and with short wide keel [Nieuwenhuijsen 2008]
3. Sternite: caudal edge subgenital plate somewhat incised or straight [Nieuwenhuijsen 2008]
Literature
Eberhard 1970 Eberhard, W., 1970. The predatory behavior of two wasps, Agenoideus humilis (Pompilidae) and Sceliphron caementarium (Sphecidae), on the orb weaving spider Araneus cornutus (Araneidae). Psyche: A Journal of Entomology, 77(2), 243-251.Gros & Wahis 2002 Gros, E., & Wahis, R., 2002. Contribution à la connaissance des Agenioideus de la faune franco-belge (Hymenoptera, Pompilidae). Bulletin de la Société entomologique de France, 107(3), 313-334.
Nieuwenhuijsen 2008 Nieuwenhuijsen, H., 2008. De spinnendoders van Nederland (Hymenoptera: Pompilidae). Jeugdbondsuitgeverij.
Notton 2018 Notton, D., 2018. The spider wasp, Agenioideus apicalis (Hymenoptera: Pompilidae) new to Britain, and a second British record of Agenioideus sericeus. British Journal of Entomology & Natural History. 31.
Peeters et al. 2004 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.
Soortenregister Nederlands Soortenregister
Waarneming.nl Waarneming.nl
Citation
Krischan, O.R., 2025. Agenioideus sericeus. Kerfdier, www.kerfdier.nl. Accessed on 12 May 2025.