SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '402810e308a975d1a6083ac2e30f7465c8088da560b8f7c9941b7665fd07ae2a' 
  AND token = 'jOJNCQyrSSBCkuGmslcIgWIyQSOlTzhR4kjWCAqRzss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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