SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f8b2579fb2f037a2f03d0f0dbc08436402e318ec3e415bc1d5d08525af08c3d' 
  AND token = 'MvCnIKxNxHQxrSufNpYt+GnKyYEnDl6hzVwANYlKpDU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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