SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ce23aaf191567358be12b5113bb705300ad1ea710a41a5040daf8d0a9c851221' 
  AND token = 'trZlX7yOk1qWGEnImRulhCkFsnSlVilyaC5sYi6csEs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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