Dasymutilla bioculata    




habitat
Arid sandy regions.

seasonality
Adults may be found from June to September.

identification
These wasps are antlike in appearance (Manley and Pitts 2002). Compound eyes somewhat hemispherical. Felt line only present on tergite II. Females: 6-19 mm long and wingless (Williams and Pitts 2013). Setae not plumose (Manley and Pitts 2002). Colour of head and mesosomal integument uniform, ranging from black to reddish-brown (Williams et. al. 2013). Colour of dorsal mesosomal setae also typically uniform. Colour of propodeal, pronotal, and mesonotal setae uniform. Head narrower than pronotum and lacking tubercles posteriorly. Mandibles apically bidentate and nearly straight. Mesonotum rounded laterally. Mesosoma elongate with prominent scutellar scale and raised transverse carina anteriorly. Pygidium with at least 15 narrow grooves. Males: 8-20 mm long and winged. Colour of tergite 2 with yellow to orange areas or entirely reddish-brown. Setal colour of tergites 3-7 uniform, black or orange. Setae of legs, mesonomal pleurae, and propodeum entirely black. Clypeus somewhat bidentate anteriorly with transverse lamella connecting teeth. Mandibles lack notches ventrally (Manley and Pitts 2002). Wing venation normal with a sclerotized pterostigma. Axilla prominent and truncate posteriorly (Manley and Pitts 2002; Williams et. al., 2013). Notauli absent. Tegulae lack pubescence posteriorly (Williams et. al., 2013). Mesopleuron rounded. Two spurs present on mesotibia (Manley and Pitts 2002). Setae on apical end of pygidium (Williams et. al., 2013). Cuspis curves downward and has dense setae ventrally and laterally.

life history
Solitary ectoparasites of ground-dwelling wasps and bees (Mickel 1928). Adult females enter host nests and deposit eggs into diapausing larvae or pupae (Arneson and Pitts 2003). The parasitic larvae then consume the entire host before entering the prepupal stage (Mickel 1928). The size of adults is believed to depend directly on the size of the host larva. Thus, host availability may be the cause of geographic, seasonal, and annual size differences (Deyrup and Manley 1986). Also, females may determine whether to release or withhold sperm upon oviposition depending on host size. As they search for hosts, adult females build new retreats daily (VanderSal 2008). Adults are inactive midday when temperatures are highest (Mickel 1928); however, females have a higher tolerance to high temperatures than males. This is likely due to their reduced mobility. Adult females are reputed to have a very painful sting.

conservation
Not currently of any concern.

diet info
Currently known larval hosts: Bembecinius quinquespinosus (Say), Bembix americana spinolae Lepeletier, Bembix amoena Handlirsch, Bembix pruinosa Fox, Bembix sayi Cresson, Bembix texana Cresson, and Microbembex monodonta (Say) (Williams and Pitts 2013). It is speculated that adult females eat nectar and larvae from host nests (Brothers 1989).

range
Southern British Columbia east to Manitoba, south to Louisiana & New Mexico, and Mexico (Manley and Pitts 2007).

notes
Information is somewhat limited on Dasymutilla species. Sex association is challenging due to sexual dimorphism and differences in geographic ranges between conspecific males and females. This has been true for Dasymutilla bioculata, which now has over 20 junior synonyms (Williams et. al., 2011). The brief nature of mating in this group reinforces this challenge by making it difficult to find copulating pairs. Another challenge is the study of larval hosts which requires digging up host nests for identification (Hennessy 2002). According to Mickel (1928), the type specimen for Dasymutilla bioculata is a male from Colorado territory and is located in the collection of American Entomological Society of Philadelphia.

people
species page authorWingert, B.2013 

quick link
http://entomology.museums.ualberta.ca/searching_species_details.php?s=39064

 

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