SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '23d7e2830007ed1bce16eeff425584209046af39d616f191cb011bff4ace8727' 
  AND token = 'h+mUN9nxABbqmPoTVGtgoIERgWk3YoZtLOKB2OUOJ3o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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