SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6f66d80ffc318aba2a7ad84678171b3067e987bf8225fb7223f8e609e120727e' 
  AND token = 'pu9hGOKFpdQXK94avDwww+2zpxn6u9glHCZY69i3B8Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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