SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '485832a2aa1539910d0205a0cea4b1ac9ee665f36832c8a68f56282893b9aa12' 
  AND token = 'k2TdZGVBZO4axAAWd6+G9GUtAIZdKCg0rq3n65PZMk0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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