SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1a17c1eb4412d128a30710c9e21931d5900f503c9c7d08c69a9a4f564d016983' 
  AND token = 'KbqvSinq5lqzpYa4WkbgNQTCS6Hnq5zVjDd/esMiw00=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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