SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef1af9ad9bd044def0eedfd8abfabea61fd4fcdb6ed949f4ed9b530861f6b4e2' 
  AND token = '/ZpwRNCQ+GdZIae2JoLJoGTFgT38RoySIW5Bgd7UWC4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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