SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '897bdc3481ce64aabef906c8ad127c0d9170149b226c3085fe73aae6cc63c63d' 
  AND token = 'DqaQabiI1ROw5xDGe7T+erWGvx4xnVhYkotcM27JvMI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}