SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '70158c53b693906384452f4e83ee11b9bc204572cc714f3738d52734737d7753' 
  AND token = 'ahXQTAY5iQ1VZH+JCZIi+86wfk/tu73hYeQHpIdU590=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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