Ryasnyansky's first name is written either Mihail, Mikhail or Michael.
He studied under Tetyana Yablonska. Later he taught at the Kiev Art Institute.
His portraits have simple backgrounds and a controlled focus on the face and hands, with other areas handled more softly and broadly.
His drawings are soulful, with a keen sense of tonal values.
He was an avid outdoor painter, and his on-the-spot landscapes are painted with bold colors and thick paint.