Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'dfc52050e3d365d9e0cafb2fa93d310913bafc64f5db8bd38250a20e448965e1' 
  AND token = 'UPnH0C7LZxBzEsEoAa62G+MKMaKOJyzeJ9oKoDhgMnQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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