SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07b173b5a937edd844639c60bf5a92a7a59ead37d6160d978eee35812840b534' 
  AND token = 'm2uaEppE+DaTMFiIv+twiNKQJZBmfdDlIz6IfrFA8o0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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