SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'de55beff01b0b8b2dad184c0fe3ba04186b7f9dfb89764bfabf41b3df70ad860' 
  AND token = 'PzruWYDN9gw+7WA+AiRoUDLj+pp/9BNI0qLnCzEQnBs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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