SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80b1222b732852085fb7dde3c68096bc5c8dc5d633f75d4bfea00f610949ce9e' 
  AND token = 'mZRzrKCB5OJYmOcOAdFGaj+eEJ7ZZQHaHCHimGQDAz4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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