SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b9046b5c1c3d6b48b0487d66424a561620676fefe6f19dc526e0963972f3de64' 
  AND token = 'Xiu0BS4dMHN9f0H7bIgettw4AbcxvA2mYW8WcvKj7w4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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