SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cace822fd496de254e3dc71fe4da66f3f38510fbf703c5ba6ea674a334905236' 
  AND token = 'o5TZlA9Rnw+ahie122NgcLWfKM3QvrfRRFGHWpdS/Rw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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