Lacunosus

Clouds : classification
Genera Cirrus Ci Cirrocumulus Cc Cirrostratus Cs Altocumulus Ac Altostratus As Stratocumulus Sc Stratus St. Cumulus Cu Nimbostratus Ns Cumulonimbus Cb	species calvus cal capillatus cap castellanus cas congestus con fibratus fib floccus flo fractus fra humilis hum lenticularis len mediocris med nebulosus neb spissatus spi stratiformis st uncinus unc volutus vol	Subspecies duplicatus you intortus in lacunosus la opacus op perlucidus pe radiatus ra translucidus tr undulatus un vertebratus ve Special forms arcus arc asperitas asp cauda cau cavum cav fluctus flu flumen flm incus inc mamma mam murus mur pannus pan pileus pil praecipitatio pra tuba tub velum vel virga vir

Lacunosus (la) ( Latin for "patchy") are cloud spots, fields or layers that are usually quite thin and have, as essential features, more or less regularly distributed round holes, the edges of which are often frayed. The cloud parts and cloud-free spaces often create the impression of a network or honeycomb.

The term is mainly used for cirrocumulus and altocumulus and - albeit very rarely - for stratocumulus .

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  Cirrocumulus lacunosus: Holey, frayed cloud layer in the upper half

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  Stratocumulus lacunosus before a thunderstorm