SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5bdc0c7b35501dfece81efb651dff264b47d6b953ea6a14377853c60017582e4' 
  AND token = 'NRvHBYeYdlWxzqtFGC6aXEri2Xbj1l9o2eJaH6waQMY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}