SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9cffde10e1677fd48d752cec5602f5bbf2f85a45a157fe7ec2d46a6fe43c0d72' 
  AND token = 'AarP3YZQ8LZIJlUtqym4IXFHHLqEWoBxt94bVmYZt4k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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