Short-beaked Echidna
Tachyglossus aculeatus
7 cm
Penis length (state not stated in source; 'about')
More than one head, Spiny
The glans has four rosette-tipped heads. Only two are used at once, and the left and right pairs take turns.
Margin note: With four heads and only two in use at a time, it rotates them like a careful driver rotating tyres.
Sources
- Rismiller P.D., Grützner F. (2019) Tachyglossus aculeatus (Monotremata: Tachyglossidae). Mammalian Species 51(980):75–91 doi:10.1093/mspecies/sez012
- Johnston S.D., Smith B., Pyne M., Stenzel D., Holt W.V. (2007) One-sided ejaculation of echidna sperm bundles. The American Naturalist 170(6):E162–E164 doi:10.1086/522847
- Fenelon J.C., McElrea C., Shaw G., Evans A.R., Pyne M., Johnston S.D., Renfree M.B. (2021) The unique penile morphology of the short-beaked echidna, Tachyglossus aculeatus. Sexual Development 15(4):262–271 doi:10.1159/000515145
- Griffiths M. (1989) Tachyglossidae. Chapter 15 in Walton D.W., Richardson B.J. (eds) Fauna of Australia, Vol. 1B Mammalia. Australian Government Publishing Service, Canberra link
Drawn from
- Johnston et al. 2007, Fig. 2A: Erect lateral view: shaft, basal collar, Y of engorged rosettes, retracted pair (arrow)
- Fenelon et al. 2021, Figs 1c, 1h, 3a: Four-rosette cluster, distal spines, everted side view
- Griffiths 1989 (FoA ch. 15), Fig. 15.8: Male excretory and reproductive organs with the preputial sac removed to show the (resting) penis; after Griffiths 1968
- Griffiths 1989 (FoA ch. 15), p. 31: Page render of the 'Male System' text containing the 70 mm statement
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