Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'f0e4a12b41a416e8ba9c1a02aa20798ab53d2ea239bcb316544a723c1b1fd346' 
  AND token = 'SBSYPGHUDG8LaHn/XTDp8cHGj1VR3c92HKJhbVW7urw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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