Pikmin 2.5/Treasure Hoard

All 301 treasures in Pikmin 2.5. 284 have been named so far.

Juicy Banquet Series
These treasures are all kinds of fruit; all of which appeared in Pikmin 3. There are 12 treasures in this series:

Nutritious Greens Series
These treasures are all kinds of vegetables, such as peppers and roots. There are 8 treasures in this series:

Natural Scenery Series
All of these treasures are forms of plantlife. There are 8 treasures in this series:

Fattening Series
All of these treasures are basic food products. There are 7 treasures in this series:

Sealed Luxuries Series
All of these treasures are food and drink containers. There are 18 treasures in this series:

Dream Sweets Series
These treasures are all candy and sweets. There are 15 treasures in this series:

Sea Bounty Series
These treasures are all things that wash up on beaches, such as shells. There are 9 treasures in this series:

Buried History Series
Each of these treasures is some kind of ancient item. There are 19 treasures in this series:

Application Series
All of these treasures are school supplies. There are 10 treasures in this series:

Fun Trinkets Series
This series is comprised of various toys and knickknacks. There are 17 treasures in this series:

Fallacy of Man Series
All of the treasures in this series are items related to gambling. There are 6 treasures in this series:

Abstract Battlement Series
All of the treasures in this series are board game components. There are 9 treasures in this series:

Active Toys Series
Every one of these treasures relates to some type of sport. There are 6 treasures in this series:

Spooky Series
All of these treasures are Halloween related items. There are 8 treasures in this series:

Fabric of Giants Series
This series is composed of various types of headwear. There are 5 treasures in this series:

Modern Utilities Series
All of these treasures are common household items. There are 9 treasures in this series:

Medical Discoveries Series
These treasures are all medical products. There are 12 treasures in this series:

Repair Kit Series
All of these treasures are tools. There are 6 treasures in this series:

Technological Series
Each of these treasures is a kind of technological object or component. There are 14 treasures in this series:

Unknown Energy Series
These treasures are composed of batteries. There are 5 treasures in this series:

Ancient Currency Series
These treasures are all forms of currency. There are 9 treasures in this series:

Extraterrestrial Logo Series
Each of these treasures is a pin/badge with a logo on it. There are 30 treasures in this series:

Nostalgic Memories Series
All of these are Nintendo related items. There are 13 treasures in this series:

Astral Beauty Series
These treasures are all star-cut crystals, a reference to Paper Mario:The Thousand Year Door's Crystal Stars. There are 7 treasures in this series:

Explorer's Buddy Series
All of these treasures are parts of the Exploration Kit in Pikmin 2, aside from 3 new ones which give new abilities. There are 16 treasures in this series:

Captain's Bestiary Series
These treasures are all trophies modeled after the various enemy types found in the game. They are only found in the Pit of 100 Trials.

*SPOILER* Series
These are all treasures from SPOILERS