SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4dcd72ccfc68cfe233b39ec87a9a4d053f09ad3cabab439c9c8c56a77e29eb71' 
  AND token = 'bWfphEFRtVI74h4wqL02NdVDGonj0iRRXtwigDIlSV8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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