SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c74767a2fbe081f0a43f7e0fff852c42b871eee785a88a6c3d979e2f72a06f1' 
  AND token = 'ONrVNv20pVUBEkYhWRnsBCz/LKxWfmx1XtRkNvZVFY4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}