SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '920143592b20c25a9cc3f7aa82aabfd46d544f9ca10ac3a5833a1d1c9faa7a5b' 
  AND token = 'SyVRLY8o/OdUNfNksQapvZdewHK6YRIaRYf4yqD9t8I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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