SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '925b0610d713c9f302e42813d7cf112607f3938302c41d80e969118f7b7bbaa1' 
  AND token = 'DEp+G65eRlCVwifmVZ+xXQsBgc2JGa9/eI9BeymAFZo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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