SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'fadc1a8af4d9c65a61582a02a5969b781a98eac761996e9602dfb790436a6824' 
  AND token = 'Z+jyckMbjmNjP8n21TZYubqfXV8FarRfxwLX4cEuC88=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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