SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ef9326f04ff22a3c6233c12a828ab5b1cd34bc202b935a2aedfb7a5089dc4d2a' 
  AND token = 'H6JYvlxjUvHgYNxtNO8stqdZg+NYX1unwUJQhKTxHQg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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