SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '5c29929d0c0284e587dc313d3f12a171b772be1ef709b0b7a21f35360291c54d' 
  AND token = '3JsBtDRT3gazV+JzGDBkK79ZOw2uKUZ6q1sX+cjdqZM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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