SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6c234aa4b3c715d80036d304be9da330d73538ae6b7957ce2ca37a68630a42cd' 
  AND token = 'UEb7IwbBziyfmYWUprvC7lfDBRQfEtmsmlPB8oFdAHk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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