SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01b45b5c3f6fc0e4fadb83d89a1afe42198da1026e68ecad7616b988cf6f0382' 
  AND token = 'HTKEiEmQ1oc+g9fVAbwrBnHw+DHrBsvqQg/NaPGJg1Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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