SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5cd0aafa92b7572fad8fb9e06f8993b1ec3e3a1a82b72012e77db4ec0baeeb37' 
  AND token = 'lzkTNJ/xq3jRt6xMJSTqYV4HSRX363upa9LhiAaTnzc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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