SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '559580d717f79e96f8ae1e64a67dcc0f288ccabe2be5a831b034e728ba0cacbe' 
  AND token = 'fzpHPN3LqfqUMepPe6AG+cSKmfQMOqDrUevbWQd9dfY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00327

JSON explain

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