SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8da626eaf6ef29a1ccc5283ea594b20223bdbed7dfbf1d9fc8e82a86dff9d15f' 
  AND token = 's0cf5eYFdmWUi7GNDmK8jEryeWy9k5YMizwxUqGKa4s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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