SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fd1406d2213e5e1f2264dc0943cb7c77a125c5528576e6719ff1e9b8f960e36a' 
  AND token = 'JZi91xbsDnfcqd9V8xwztfSf8DBUoxSZKRdQjmT17Oc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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