SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd94e1b482fb32c255c0847f35a557f42b76e85507f8481d5b3ae36fca55811cc' 
  AND token = 'A/14VvGTi2MKdMzauJ288whN9ZIGqLvLocYj+NNhOHw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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