SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fcba8330a61b5d9149bea3e93f4b6ffdb3c22df1b381cf95e1bf837ba2ad0b95' 
  AND token = 'oN3G/sZ/YhSw2G6DLVzOqbc0Mp8rQOIHBmwBcOpmgiA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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