SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a0c42e65e3d1e33e16b0ce410b769b3bd1f57f531a9874e0401feb1e9da9af1' 
  AND token = 'yIiR/K6Ix5YjKzNjuB1vw7lXLiifhWfdP7ieyx8lHmc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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