SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '691872e5648e488e04b31ae94d69cc7750afdacd197893975751ab08e176070d' 
  AND token = '+p35Eym1OYbOvGPHsVzVirZcXpyCH1pgVArqgqk3Evk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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