SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '1410775391a32676e28c80c6819fe29b26792a977b4552d84ca301326e5fbedb' 
  AND token = 'lqTOK8/+SBHYtclcZ3wkzThY3R1ic9AHPOjdLIg7N7M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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