a sick one
It refers to a leaf or shell having a scalloped edge
The black-headed ash sawfly is an insect that has an elongated black body with black dots, black wings, and red thorax. The insect in question (Tethida barda) looks completely different in its larval stage -- other than having a black-colored head -- what with a cream-colored body with front to rear yellow edging and green-patterned lengthwise stripes. Its favorite food plant for the above-mentioned, leaf-feeding larvae will be ash (Fraxinus spp) trees.
Scalloped shapes are a characteristic for example of volcanic glass, of some leaf margins, and of some barks. Conchoidal, which means ~ shell-like is often used as an alternate adjective.
Dots in the leaf scar, often referred to as "lenticels," indicate the presence of vascular bundles that were connected to the leaf while it was still attached to the plant. These dots represent the points where the leaf's vascular system was connected to the stem, facilitating the transport of water and nutrients. In some species, the arrangement and number of these dots can also help in identifying the plant species. Overall, they provide important clues about the plant's anatomy and its growth habits.
the dots are little indicators of amounts of carbon dioxide in the leafs, in other words, it shows oxygen deficiencies
Mosses (and ferns, too) reproduce by forming spores. Spores look like little black dots on the underside of a fern's leaf. I do not know what they look like on mosses.
A black willow leaf is a simple leaf.
Black Leaf on Green Background was created in 1952.
black
When a leaf is covered with black paper, it cannot receive sunlight, which is necessary for photosynthesis. Without sunlight, the chlorophyll in the leaf breaks down and the leaf turns black due to the accumulation of other pigments such as anthocyanins and carotenoids.
The leaf turned blue-black when iodine was added because iodine reacts with starch, which is present in the leaf. This reaction forms a blue-black complex, indicating the presence of starch in the leaf.
Ryukyu black-breasted leaf turtle was created in 1931.