vs Cock-tailed Tyrant

Cocconeis placentula compared with Alectrurus tricolor

Key Differences

is Not Evaluated while Cock-tailed Tyrant is Vulnerable.

Taxonomic Classification

Rank		Cock-tailed Tyrant
Kingdom	Chromista (โครมิสตา)	Animalia (สัตว์)
Phylum	Ochrophyta (Ochrophyta)	Chordata (สัตว์มีแกนสันหลัง)
Class	Bacillariophyceae (Bacillariophyceae)	Aves (นก)
Order	Achnanthales (Achnanthales)	Passeriformes (นกเกาะคอน)
Family	Cocconeidaceae	Tyrannidae
Genus	Cocconeis	Alectrurus
Species	Cocconeis placentula	Alectrurus tricolor

Conservation Status

NE — Not Evaluated

Cock-tailed Tyrant

VU — Vulnerable

Physical Characteristics

Attribute		Cock-tailed Tyrant
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Habitat

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

Range

Distributed across Brazil, Norway, Portugal, Sweden, and Taiwan.

Cock-tailed Tyrant

Habitat

Typically found in various aerial, terrestrial, and aquatic environments.

Range

Found in Norway. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Cocconeis placentula is among the most ubiquitous and widely studied freshwater and brackish-water diatoms worldwide, serving as a model organism for periphyton ecology and a key species in biological assessment of water quality. A member of the family Cocconeidaceae, this adnate epiphyte produces a characteristic ovoid frustule with fine transapical striae, a well-developed raphe system on one valve, and an elaborate pattern of areolae visible under electron microscopy. The species complex encompasses several morphological varieties (var. placentula, var. lineata, var. euglypta, var. acuta) that differ in fine structural details of the valve ornamentation. Cocconeis placentula colonizes the surfaces of aquatic plants, algae, rocks, and sediment particles in rivers, lakes, and ponds across a vast global range spanning Europe, the Americas, Asia, Africa, and beyond, tolerating a wide range of water temperatures, pH values, and moderate nutrient enrichment. Its abundance varies dramatically with substrate type, light availability, and water chemistry, making community composition data involving this species valuable in diatom-based paleolimnological reconstructions and modern bioassessment indices. As a benthic primary producer, C. placentula contributes substantially to the productivity of the photic benthos and serves as a dietary component for invertebrate grazers. Its remarkable cosmopolitan distribution and ecological flexibility make it one of the defining species of freshwater periphyton communities globally. Conservation status is not formally assessed.

Cock-tailed Tyrant

The cock-tailed tyrant (Alectrurus tricolor) is a striking and unusual flycatcher in the family Tyrannidae, named for the remarkable elongated, spatula-shaped outer tail feathers of the male, which can exceed the body length and are displayed during aerial courtship flights over open grasslands. The species inhabits wet and seasonally flooded grasslands, cerrado savanna, and campos in the interior of South America, including central Brazil, eastern Bolivia, Paraguay, and northeastern Argentina — not Norway, as erroneous database entries suggest. Males combine conspicuous black, white, and rufous plumage with their extraordinary tail streamers in an elaborate display to attract females on leks; females are cryptically streaked brown. The cock-tailed tyrant is a ground- and low-vegetation forager, preying on insects and other small invertebrates gleaned from grass stems and caught in aerial sallies. The species is classified as Vulnerable by the IUCN due to extensive and continuing conversion and degradation of its native Neotropical grassland habitat through intensive soy and sugarcane agriculture, cattle ranching, fire management changes, and drainage of seasonally flooded grasslands. Populations have declined significantly across much of its range, particularly in Brazil and Paraguay. The species is a flagship for threatened grassland conservation in South America, where relatively little protection has historically been directed at open-country habitats compared to forest ecosystems.