SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '38a96f2410b5a2bf7829816de646895899887d26160d7637a930547318b42af6' 
  AND token = 'OfIfQYSgW7NPxRJiA+xmevD4MQ5qHKk9vgWitefMSj0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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