SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '160c99f4ff4b3eb4832847822e99ffbd9b299246e348133871a007870257c252' 
  AND token = '9DHSwrkZ3St/OVq2pOHmrjnY5osZO3uNmpkdZqKWghY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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