SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ff42cc1530d57998d7262a5a57484a2f2747b29a3b6e48545a492522491044b' 
  AND token = 'hv/C1FuOv7nUk5rIJ+8o7Jwul2EtpWmb0GwxLTRyTEg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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