SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd0f67934bf5ea610eca8aa283bb537faa7a761efba59e3c6856e8049e850fbf4' 
  AND token = 'QLSMzAZSPI/JygXjxjHgWKpHKO7afvnNtBs3UeMVMlQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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