SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '263673f626f84f0a256cff9840954f5e53a7024a948560a32f06bcd4152ae61c' 
  AND token = 'go7CjCFmDvwugRKJs48mtf3hqKd2Le5PrJnu/fHodCg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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