SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '154666f7fa264fd96c2e7f7785ad64f8a32ddbb997992338aceebbbd631bbc71' 
  AND token = 'VNyibkTsgRX7uXdbOOaIhoaHFwntBZ5KLpdGZ9aTnGU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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