SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0bb4d6741b049a37ffb6dc59a4920620d4b9d5038b49917b68ff05835851145c' 
  AND token = 'Ykl9twoiURIZ7odmMmMvk6ZekuCdQiKzXZTxo5gR9W4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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