Summary
Photorefraction and photokeratometry were performed on two juvenile tuatara (Sphenodon punctatus, 7 years of age, total length approx. 27 cm). Sphenodon is the only surviving genus of the Rhynchocephalia, an order of reptiles. Both existing species are endangered and are found only in New Zealand. Even though Walls (1942) has stated that the ciliary muscle is relatively weak in tuataras, we observed 8 D of accommodation. The eyes were found to focus independently and we could induce an anisometropia of 6 D. The average corneal power of the tuatara was found to be 101 D.
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Schmid, K.L., Howland, H.C. & Howland, M. Focusing and accommodation in tuatara (Sphenodon punctatus) . J Comp Physiol A 170, 263–266 (1992). https://doi.org/10.1007/BF00191413
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DOI: https://doi.org/10.1007/BF00191413