皮膜骨（英語：dermal bone 或 investing bone 或 membrane bone）是脊椎動物骨骼內膜內組織硬化形成的骨質組織。皮膜骨出現在頭骨、顎骨、鰓蓋、肩帶、魚鰭以及甲殼（龜類）中。不同於硬化軟骨（endochondral bone），皮膜骨並不來源於鈣化的軟骨組織[1]。皮膜骨與真皮一同形成，並在隨後成骨細胞的發育中不斷累積。
儘管在顱骨頂和顱後結構中皮膜骨的形狀和數量都有所變化，但脊椎動物都保留了一些皮膜骨的功能。 在硬骨魚中的魚鰭和鱗片中都發現了皮膜骨。鎖骨是皮膜骨的一個特殊例子。一些皮膜骨功能涉及生物力學方面，例如保護自身免受掠食者的捕食[2][3][4]。 皮膜骨還被認為與生態生理有關，例如取暖時在身體與周圍環境之間進行熱傳遞（如鱷魚）[5]，以及長時間呼吸暫停期間骨骼對酸中毒的中和（如鱷類和海龜）[6][7]。 這些生態生理功能取決於在皮膜骨內部或其上方的血管網絡[8]。
de Buffrénil, V.; Clarac, F.; Fau, M.; Martin, S.; Martin, B.; Pellé, E.; Laurin, M. Differentiation and growth of bone ornamentation in vertebrates: a comparative histological study among the Crocodylomorpha. Journal of Morphology. 2015, 276 (4): 425–445. PMID 25488816. doi:10.1002/jmor.20351. Chen, I.H.; Kiang, J.H.; Correa, V.; Lopeza, M.I.; Chen, P.Y.; McKittrick, J.; Meyers, M.A. Armadillo armor: mechanical testing and micro-structural evaluation.. Journal of Animal Ecology. 2011, 4 (5): 713–722. doi:10.1016/j.jmbbm.2010.12.013. Broeckhoven, Chris; Diedericks, G.; Mouton, P. le Fras N. What doesn’t kill you might make you stronger: functional basis for variation in body armour. Journal of Animal Ecology. 2015, 84: 1213–1221. PMID 26104546. doi:10.1111/1365-2656.12414. Clarac, F.; Goussard, F.; de Buffrénil, V.; Sansalone, V. The function(s) of bone ornamentation in the crocodylomorph osteoderms: a biomechanical model based on a finite element analysis. Paleobiology. 2019, 45 (1): 182–200. doi:10.1017/pab.2018.48. Clarac, F.; Quilhac, A. The crocodylian skull and osteoderms: A functional exaptation to ectothermy?. Zoology. 2019, 132: 31–40. doi:10.1016/j.zool.2018.12.001. Jackson, D.C.; Goldberger, Z.; Visuri, J.; Armstrong, R.N. Ionic exchanges of turtle shell in vitro and their relevance to shell function in the anoxic turtle. Journal of Experimental Biology. 1999, 202: 503–520.
Jackson, DC.; Andrade, D.; Abe, AS. Lactate sequestration by osteoderms of the broad-nose caiman, Caiman latirostris, following capture and forced submergence. Journal of Experimental Biology. 2003, 206: 3601–3606. doi:10.1242/jeb.00611. Clarac, F.; de Buffrénil, V.; Cubo, J.; Quilhac, A. Vascularization in ornamentedosteoderms: physiological implications in ectothermy and amphibious lifestyle in the crocodylomorphs?. Anatomical Record. 2018, 301: 175–183. doi:10.1002/ar.23695.
