SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9873d6612a307b83efbee54936f4614a97261617225c40566d89d3f6b175a061' 
  AND token = 'pIXQLisexmrWPTGMtSeUcvySxVlJnZW4qV7CJxtgkZA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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