Common Quillwort vs S̄eụ̄x krong

Isoetes lacustris compared with Panthera tigris

Key Differences

Common Quillwort is Least Concern while S̄eụ̄x krong is Endangered.

Taxonomic Classification

Rank	Common Quillwort	S̄eụ̄x krong
Kingdom	Plantae (พืช)	Animalia (สัตว์)
Phylum	Tracheophyta	Chordata (สัตว์มีแกนสันหลัง)
Class	Lycopodiopsida (Lycopodiopsida)	Mammalia (สัตว์เลี้ยงลูกด้วยน้ำนม)
Order	Isoetales (Isoetales)	Carnivora (สัตว์กินเนื้อ)
Family	Isoetaceae	Felidae (Cats)
Genus	Isoetes	Panthera (Big Cats)
Species	Isoetes lacustris	Panthera tigris

Conservation Status

Common Quillwort

LC — Least Concern

S̄eụ̄x krong

EN — Endangered

Population: ~4.5K

Trend: Increasing ↑

Physical Characteristics

Attribute	Common Quillwort	S̄eụ̄x krong
Diet	—	Carnivore
Average Lifespan	—	20 years
Average Length	—	3.0 m
Average Weight	—	220.0 kg

Habitat & Geographic Range

Common Quillwort

Habitat

Native to Europe and North America, inhabiting ecosystems characteristic of the region.

Range

Found across Europe (5 countries) and North America (Canada, United States).

S̄eụ̄x krong

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical dry broadleaf forests, and tropical and subtropical grasslands and savannas, among 6 distinct biome types spanning the Neotropic and Oceanian realms. Populations are also found in montane and highland environments at higher elevations.

Range

Distributed across Colombia and Ecuador. Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Common Quillwort

The Common Quillwort, <em>Isoetes lacustris</em>, is an aquatic vascular plant in the family Isoetaceae, a relict lineage representing one of the most ancient groups of vascular plants, related to the giant lycopsid trees of the Carboniferous period. It is native to Europe and North America, where it typically grows submerged in cool, clear, oligotrophic lakes and slow rivers on sandy or gravelly substrates at low to mid elevations. <em>Isoetes lacustris</em> is characterized by its rosette of quill-like, hollow, dark green leaves emerging from a lobed corm-like base, typically reaching 10 to 20 centimeters in length. The sporangia, which produce megaspores and microspores, are embedded at the swollen bases of the leaves. The species reproduces via spores and is entirely submerged, absorbing carbon dioxide and nutrients from the sediment and water column. It is highly sensitive to water quality deterioration, including eutrophication and acidification, and its presence is considered an indicator of pristine lacustrine conditions. The Common Quillwort is assessed as Least Concern on the IUCN Red List. Biological traits such as average lifespan, body size, and specific dietary preferences remain poorly documented for this species.

S̄eụ̄x krong

The largest wild cat on Earth, tigers can exceed 300 kg and inhabit forests from the Russian Far East to Southeast Asia. Solitary ambush predators with distinctive orange and black striped coats that provide camouflage in dappled light. Critically endangered, with fewer than 4,000 remaining in the wild due to poaching and deforestation.