Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '3186328552f5519d9d3cb12dcce31f2013704225281fb87cb1e40b7af9585bb5' 
  AND token = 'CUNnTURwJrOZoZI1Zn8HxD1ZVpTpeuYPxRaLUic5230=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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