There's a development concerning the salarian ark. Kallo has the information.
To start this quest, you should read the email "About the Paarchero" from Kallo. I received this email after completing objective "Discuss your options with the other Pathfinders" of The Journey to Meridian mission.
Hello, Ryder:
Please come and talk to me when you have a chance. We just received something very odd. I think it's connected to the salarian ark.
Kallo
Meeting Point
Havarl
Kett Handler
Voeld
Hayer or Raeka
Nexus / Hyperion
Rand Lon's Apartment
Nexus / Hyperion
Crashed Shuttle
Elaaden
Scavengers Camp
Elaaden
Draullir Cave
Kadara
An anonymous message suggests sinister motives behind the capture of the salarian ark. Follow the leads to uncover the truth.
Find and scan the container.
Examine the container. Saelen will appear.
It's in one of the buildings in Techiix.
Enter the apartment and scan big plant, dust traces and personal terminal.
You will meet Rand Lon outside.
Follow the footprints to the scavengers camp.
"You both used me" or "He wasn't working alone".
"Agreed, but we lack leverage" or "I don't trust you".
He is in the Draullir Cave.
"Done. Freedom for intel" (additional journal entry - Kett: Secret Intelligence but Saelen gets upset) or "Let's arrest him".