Sphex Rugifer

Wasps of the genus ''Sphex'' (commonly known as digger wasps) are cosmopolitan predators that sting and paralyze prey insects. ''Sphex'' is one of many genera in the old digger wasp family Sphecidae ('' sensu lato''), though most apart from the Sphecinae have now been moved to the family Crabronidae. There are over 130 known ''Sphex'' species.

Behaviour

In preparation for egg laying, they construct a protected "nest" (some species dig nests in the ground, while others use pre-existing holes) and then stock it with captured insects. Typically, the prey are left alive, but paralyzed by wasp toxins. The wasps lay their eggs in the provisioned nest and the wasp larvae feed on the paralyzed insects as they develop.

The great golden digger wasp ('' Sphex ichneumoneus'') is found in North America. The developing wasps spend the winter in their nest. When the new generation of adults emerge, they contain the genetically programmed behaviors required to carry out another season of nest building. During the summer, a female might build as many as six nests, each with several compartments for her eggs. The building and provisioning of the nests takes place in a stereotypical, step-by-step fashion.

''Sphex'' has been shown, as in some Jean Henri Fabre studies, not to count how many crickets it collects for its nest. Although the wasp instinctively searches for four crickets, it cannot take into account a lost cricket, whether the cricket has been lost to ants or flies or simply been misplaced. ''Sphex'' drags its cricket prey towards its burrow by the antennae; if the antennae of the cricket are cut off, the wasp would not think to continue to pull its prey by a leg.

The navigation abilities of ''Sphex'' were studied by the ethologist Niko Tinbergen. Richard Dawkins and Jane Brockmann later studied female rivalry over nesting holes in ''Sphex ichneumoneus''.

Use in philosophy

Some writers in the philosophy of mind, most notably Daniel Dennett, have cited ''Sphexs behavior for their arguments about human and animal free will.

Some ''Sphex'' wasps drop a paralyzed insect near the opening of the nest. Before taking provisions into the nest, the ''Sphex'' first inspects the nest, leaving the prey outside. During the inspection, an experimenter can move the prey a few inches away from the opening. When the ''Sphex'' emerges from the nest ready to drag in the prey, it finds the prey missing. The ''Sphex'' quickly locates the moved prey, but now its behavioral "program" has been reset. After dragging the prey back to the opening of the nest, once again the ''Sphex'' is compelled to inspect the nest, so the prey is again dropped and left outside during another stereotypical inspection of the nest. This iteration can be repeated several times without the ''Sphex'' changing its sequence; by some accounts, endlessly. Dennett's argument quotes an account of ''Sphex'' behavior from Dean Wooldridge's ''Machinery of the Brain'' (1963). Douglas Hofstadter and Daniel Dennett have used this mechanistic behavior as an example of how seemingly thoughtful behavior can actually be quite mindless, the opposite of free will (or, as Dennett described it, sphexishness).

Philosopher Fred Keijzer challenges this use of ''Sphex'', citing experiments in which behavioral adaptations are observed after many iterations. Keijzer sees the persistence of the ''Sphex'' example in cognitive theory as an indication of its rhetorical usefulness, not its factual accuracy. Of course, the repeated inspection of a disturbed nest may very well be an adaptive behavior, thus diminishing the aptness of Hofstadter's metaphor. As he concludes, "There is no reason for humans to remain stuck in an endless behavioral loop when wasps don’t."

Species

The genus ''Sphex'' contains 132 extant species:

*'' Sphex abyssinicus'' (Arnold, 1928)
*'' Sphex afer'' Lepeletier de Saint Fargeau, 1845
*'' Sphex ahasverus'' Kohl, 1890
*'' Sphex alacer'' Kohl, 1895
*'' Sphex antennatus'' F. Smith, 1856
*''Sphex argentatissimus'' Dörfel and Ohl, 2015
*''Sphex argentatus'' Fabricius, 1787
*''Sphex argentinus'' Taschenberg, 1869
*''Sphex ashmeadi'' (Fernald, 1906)
*''Sphex atropilosus'' Kohl, 1885
*''Sphex basilicus'' (R. Turner, 1915)
*''Sphex bilobatus'' Kohl, 1895
*'' Sphex bohemanni'' Dahlbom, 1845
*'' Sphex brachystomus'' Kohl, 1890
*'' Sphex brasilianus'' Saussure, 1867
*''Sphex brevipetiolatus'' Dörfel and Ohl, 2015
*'' Sphex caelebs'' Dörfel and Ohl, 2015
*'' Sphex caeruleanus'' Drury, 1773
*''Sphex caliginosus'' Erichson, 1849
*''Sphex camposi'' Campos, 1922
*'' Sphex carbonicolor'' Van der Vecht, 1973
*'' Sphex castaneipes'' Dahlbom, 1843
*'' Sphex cognatus'' F. Smith, 1856
*'' Sphex confrater'' Kohl, 1890
*'' Sphex corporosus'' Dörfel and Ohl, 2015
*''Sphex cristi'' Genaro ''in'' Genaro & Juarrero, 2000
*'' Sphex cubensis'' (Fernald, 1906)
*'' Sphex darwinensis'' R. Turner, 1912
*''Sphex decipiens'' Kohl, 1895
*'' Sphex decoratus'' F. Smith, 1873
*'' Sphex deplanatus'' Kohl, 1895
*''Sphex diabolicus'' F. Smith, 1858
*''Sphex dorsalis'' Lepeletier de Saint Fargeau, 1845
*'' Sphex dorycus'' Guérin-Méneville, 1838
*''Sphex ephippium'' F. Smith, 1856
*'' Sphex ermineus'' Kohl, 1890
*''Sphex erythrinus'' (Guiglia, 1939)
*''Sphex ferrugineipes'' W. Fox, 1897
*''Sphex finschii'' Kohl, 1890
*''Sphex flammeus'' Dörfel and Ohl, 2015
*'' Sphex flavipennis'' Fabricius, 1793
*''Sphex flavovestitus'' F. Smith, 1856
*''Sphex formosellus'' Van der Vecht, 1957
*''Sphex fortunatus'' Dörfel and Ohl, 2015
*''Sphex fumicatus'' Christ, 1791
*''Sphex fumipennis'' F. Smith, 1856
*'' Sphex funerarius'' Gussakovskij, 1934 – Golden Digger Wasp
*'' Sphex gaullei'' Berland, 1927
*'' Sphex gilberti'' R. Turner, 1908
*'' Sphex gracilis'' Dörfel and Ohl, 2015
*''Sphex gisteli'' Strand, 1916
*''Sphex guatemalensis'' Cameron, 1888
*''Sphex habenus'' Say, 1832
*''Sphex haemorrhoidalis'' Fabricius, 1781
*'' Sphex ichneumoneus'' ( Linnaeus, 1758) – great golden digger wasp
*'' Sphex imporcatus'' Dörfel and Ohl, 2015
*'' Sphex incomptus'' Gerstaecker, 1871
*'' Sphex ingens'' F. Smith, 1856
*'' Sphex inusitatus'' Yasumatsu, 1935
*''Sphex jamaicensis'' (Drury, 1773)
*'' Sphex jansei'' Cameron, 1910
*'' Sphex jucundus'' Dörfel and Ohl, 2015
*'' Sphex kolthoffi'' Gussakovskij, 1938
*'' Sphex lanatus'' Mocsáry, 1883
*''Sphex latilobus'' Dörfel and Ohl, 2015
*'' Sphex latreillei'' Lepeletier de Saint Fargeau, 1831
*''Sphex latro'' Erichson, 1849
*''Sphex leuconotus'' Brullé, 1833
*'' Sphex libycus'' Beaumont, 1956
*''Sphex lucae'' Saussure, 1867
*''Sphex luctuosus'' F. Smith, 1856
*''Sphex madasummae'' Van der Vecht, 1973
*'' Sphex malagassus'' Saussure, 1890
*'' Sphex mandibularis'' Cresson, 1869
*'' Sphex maroccanus'' Schmid-Egger, 2019
*''Sphex maximiliani'' Kohl, 1890
*''Sphex melanocnemis'' Kohl, 1885
*''Sphex melanopus'' Dahlbom, 1843
*''Sphex melas'' Gussakovskij, 1930
*'' Sphex mendozanus'' Brèthes, 1909
*''Sphex mimulus'' R. Turner, 1910
*''Sphex mochii'' Giordani Soika, 1942
*''Sphex modestus'' F. Smith, 1856
*''Sphex muticus'' Kohl, 1885
*'' Sphex neavei'' (Arnold, 1928)
*''Sphex neoumbrosus'' Jha & Farooqui, 1996
*'' Sphex nigrohirtus'' Kohl, 1895
*''Sphex nitidiventris'' Spinola, 1851
*'' Sphex nudus'' Fernald, 1903 – Katydid Wasp
*''Sphex observabilis'' (R. Turner, 1918)
*''Sphex opacus'' Dahlbom, 1845
*'' Sphex optimus'' F. Smith, 1856
*''Sphex oxianus'' Gussakovskij, 1928
*''Sphex paulinierii'' Guérin-Méneville, 1843
*'' Sphex pensylvanicus'' Linnaeus, 1763 – great black wasp
*'' Sphex permagnus'' (Willink, 1951)
*''Sphex peruanus'' Kohl, 1890
*''Sphex praedator'' F. Smith, 1858
*''Sphex pretiosus'' Dörfel and Ohl, 2015
*''Sphex prosper'' Kohl, 1890
*''Sphex pruinosus'' Germar, 1817
*''Sphex resinipes'' (Fernald, 1906)
*''Sphex resplendens'' Kohl, 1885
*'' Sphex rex'' Hensen, 1991
*''Sphex rhodosoma'' (R. Turner, 1915)
*'' Sphex rufinervis'' Pérez, 1985
*'' Sphex rufiscutis'' (R. Turner, 1918)
*'' Sphex rugifer'' Kohl, 1890
*''Sphex satanas'' Kohl, 1898
*''Sphex schlaeflei'' Schmid-Egger, 2019
*''Sphex schoutedeni'' Kohl, 1913
*'' Sphex schrottkyi'' (Bertoni, 1918)
*'' Sphex semifossulatus'' Van der Vecht, 1973
*''Sphex sericeus'' (Fabricius, 1804)
*'' Sphex servillei'' Lepeletier de Saint Fargeau, 1845
*''Sphex solomon'' Hensen, 1991
*''Sphex stadelmanni'' Kohl, 1895
*'' Sphex staudingeri'' Gribodo, 1894
*''Sphex subhyalinus'' W. Fox, 1899
*'' Sphex subtruncatus'' Dahlbom, 1843
*''Sphex tanoi'' Tsuneki, 1974
*'' Sphex taschenbergi'' Magretti, 1884
*''Sphex tepanecus'' Saussure, 1867
*'' Sphex texanus'' Cresson, 1873
*''Sphex tinctipennis'' Cameron, 1888
*''Sphex tomentosus'' Fabricius, 1787
*''Sphex torridus'' F. Smith, 1873
*'' Sphex vestitus'' F. Smith, 1856
*'' Sphex walshae'' Hensen, 1991
*'' Sphex wilsoni'' Hensen, 1991
*''Sphex zubaidiyacus'' Augul, 2013

Fossil Species

*†''Sphex bischoffi'' Zeuner, 1931
*†'' Sphex giganteus'' Heer, 1867
*†''Sphex obscurus'' Statz, 1936

References

External links

Great golden digger wasp ''Sphex ichneumoneus'' - large format diagnostic photographs, wasp with katydid prey Online Identification Guide to eastern North American ''Sphex''

{{Taxonbar, from=Q311144

Sphecidae
Apoidea genera
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