SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72da6d958358caa3a2dec964c640a3420f047ff0a048fc6bb6cef95d29f0ba30' 
  AND token = 'p16q6PqHK+6mfUzKC71VE9rpb4kQwNrINImeYqVDAHA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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