SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a0405638599ea943d8d0b71d3277b039377594be252564fb53068ee281876036' 
  AND token = 'fWg3gqs/E9P/efPZCh14a0BkTZhgZNKec0cHYRHJvFY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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