SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd02243b9ba4985b156cf0a587e14e90ab49044f10f119dff2a2519edfb2dd5f7' 
  AND token = '3v7eCz4PXLAbwWgrbcTZxM+kymw57IJmmwlfwPcsyAw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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