SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '38baebfd7e156472f27ddc027c987b93d05fa430fd52891fc47a757ad0fa3842' 
  AND token = 'CYUcqQvZyIqR2VIoxmKu6+6aEj0r1lTizmNgkBz2xnU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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