Pseudocyphellaria haywardiorum is a species of corticolous (bark-dwelling), foliose lichen in the family Peltigeraceae. It is found in New Zealand, where it is considered "at risk" under the New Zealand Threat Classification System. Pseudocyphellaria haywardiorum has a more or less circular thallus measuring 30–80 mm in diameter, loosely attached from its edges to its centre, featuring rising wavy margins with rounded lobes that overlap in a complex pattern. The upper surface varies in colour from dark grey-blue to brown-black, becoming darker at the lobe tips when moist, and displays a spectrum of colours including dark olive-brown to pale yellowish with greyish edges when dry, while the underside is either bubbly or unevenly wrinkled with a tomentum ranging from red-brown to black-brown, and white pseudocyphellae especially noticeable in the central region.

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