SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1b27ce1646cbc21eaf9a360a7732712f7e7c6b97bee3533bd29cea77d69bb469' 
  AND token = 'gDL1xa9sFSVUNUxG+29DogKxC8ORSgZqSzICJ5nugiI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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