SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5504786190ca404e202680caf2ffc5f645b6b636bee98ae45c315f38f3cfc66b' 
  AND token = 'g2qJEj8PuY9lpyxCkKVeXGQS1ezREyU8rIp0clJlEL8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}