SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '145a3a450b2bb1d3257d77be9be04fdcf543e0a4c362a68e9f27d7b44c68bff8' 
  AND token = '8K7WJxSDwvqOGw9v2aNoiIRNPO17SQoKHbhDkrnU9Zw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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