SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b62846f5d0623d6ceecfe4432b7153c56000f6218841db91a8628eddd63603fc' 
  AND token = 'bbLIdEORgwHmSSpdEZbMWVc/PueH9VlfUxz25sD8t6M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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