Myrtis fanny

By Michael Woodruff, CC BY-SA 2.0

Etymology: Named for the Boeotian poet, muse, and teacher

First Described By: Reichenbach, 1854 

Classification: Dinosauromorpha, Dinosauriformes, Dracohors, Dinosauria, Saurischia, Eusaurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Coelurosauria, Tyrannoraptora, Maniraptoromorpha, Maniraptoriformes, Maniraptora, Pennaraptora, Paraves, Eumaniraptora, Averaptora, Avialae, Euavialae, Avebrevicauda, Pygostaylia, Ornithothoraces, Euornithes, Ornithuromorpha, Ornithurae, Neornithes, Neognathae, Neoaves, Strisores, Daedalornithes, Apodiformes, Trochilidae, Trochilinae 

Status: Extant, Least Concern 

Time and Place: Since 10,000 years ago, in the Holocene of the Quaternary 

Purple-Collared Woodstars are known from the western side of the Andes mountains (in lowland elevations) in the Northern half of South America 

Physical Description: Purple-Collared Woodstars, being hummingbirds, are extremely small dinosaurs, about 7.5 and 8 centimeters long and a little more than 2 grams in weight. Both sexes have green backs, but beyond that they look almost nothing alike. Males have long, curved bills, with blue throats and a violet stripe underneath. The rest of the belly is white. Their wings have black tips and their tails are V-shaped. The females, on the other hand, have less curve to their beaks; their bellies and under-throat are orange, and they have orange tips to their wings. They also have more rounded tails. Juveniles look like the females until they reach sexual maturity, where they either stay like that or develop the adult male plumage.  

Diet: These hummingbirds feed upon nectar from a variety of flowers (including cacti flowers), as well as some insects. 

By Hector Ceballos-Lascurain

Behavior: Purple-Collared Woodstars follow consistent routes back and forth from flower to flower, consistent in where they go and constantly on the move. Like other hummingbirds, they move their wings extremely fast in order to hover at the flower and get nectar with their long curved bills. They do rest occasionally, to bathe and sleep, but they are on the move more often than not. That being said, they do not seem to migrate, but do go up and down the altitude levels of the mountains following the blooming of the flowers. Males will fly in large semi-circles around the females, making twittering sounds at the top of the arc and making more trumpet sounds at the end of the arc. They also make chittering calls to one another while moving around, and chase flies while making different tweets. They breed from March through June closer to the equator, and more south they breed from June through October. They make nests out of plants and spider webs, placed in thin branches a few meters off of the ground. These hummingbirds lay two eggs which are incubated by the females for two weeks. The chicks are black and grey, and fledge after three weeks. They begin breeding at two years of age. 

By Arthur Grosset

Ecosystem: Purple-Collared Woodstars live in coastal scrub and the open woodland from the lowlands up to 3000 meters high in the Andes mountains, and they do not venture into more rainforested territory. They prefer the drier ecosystems for their right types of flowers. 

Other: Purple-Collared Woodstars, thankfully, are not threatened with extinction and are very common in their range; they are also very adaptable to human-created habitats. 

~ By Meig Dickson

Sources Under the Cut 

Nyctibius

Common Potoo by Gmmv1980, CC BY-SA 4.0

Etymology: Night Feeder 

First Described By: Vieillot, 1816 

Classification: Dinosauromorpha, Dinosauriformes, Dracohors, Dinosauria, Saurischia, Eusaurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Coelurosauria, Tyrannoraptora, Maniraptoromorpha, Maniraptoriformes, Maniraptora, Pennaraptora, Paraves, Eumaniraptora, Averaptora, Avialae, Euavialae, Avebrevicauda, Pygostaylia, Ornithothoraces, Euornithes, Ornithuromorpha, Ornithurae, Neornithes, Neognathae, Neoaves, Strisores, Caprimulgiformes, Nyctibiidae 

Referred Species: N. bracteatus (Rufous Potoo), N. grandis (Great Potoo), N. aethereus (Long-Tailed Potoo), N. leucopterus (White-Winged Potoo), N. maculosus (Andean Potoo), N. griseus (Common Potoo), N. jamaicensis (Northern Potoo) 

Status: Extant, Least Concern 

Time and Place: From 12,000 years ago through today, in the Holocene of the Quaternary 

Potoos are known from Central and South America, around the Equator 

Physical Description: Potoos are some of the weirdest birds alive today, looking about as ridiculous and muppet-like as any bird can really look. I’m honestly not sure if there is another living dinosaur that looks more like a muppet – and, of course, we don’t know if any extinct dinosaurs could have taken home the gold. The only probable and possible contender is the Frogmouth, which may just be the slightest amount more muppet-like, but it’s a close contest. They have distinctive faces, that are more feather than underlying tissue – their beaks stick out a bit, with a small hooked beak at the end. They have a large mouth, covered in fluff. Their eyes have a general sunken in appearance, which makes them look very large compared to the rest of the face. Their heads are very large compared to the rest of their bodies, and they have long bodies with short wings and long, fluffy tails. So, when they stand up, they look… well, they look like a stump, or a log standing up. They can then make themselves skinnier, which makes their eyes stand out compared to the rest of their bodies… which gives them the general appearance of a completely ridiculous animal. They can range in size from 21 to 58 centimeters, and range in color from reddish brown, to more orange brown, to more grey in color. This genus is not sexually dimorphic, though some species have variants in color. 

By Charles J. Sharp, CC BY-SA 4.0

Diet: Potoos eat a lot of insects – from beetles to moths, to mantids, ants, termites, cicadas, leafhoppers, and grasshoppers. 

Rufous Potoo by Eric Gropp, CC BY 2.0

Behavior: Potoos will hunt by standing extremely still on their perches – often, again, making themselves to look like a continuous log – and waiting for food to appear. Since they’re nocturnal, they are easily missed by the insects, as they blend into the background around them. Then, when they spot the prey, they launch forward, jutting forward to catch the insects and swallow them. Some species are more clumsy in this endeavor than others, though some are able to make leaps over several meters in order to grab the food they desire. They then return to the same post, returning to their previous log-like stillness as they wait for more food to appear. They’ll look around for the food by turning their heads rapidly from side to side – weirdly like owls, though they are not closely related to them at all. These perches can be only one meter off the ground, or up to 19 meters, depending on the forest around the potoo in question. 

Common Potoo by the American Bird Conservancy

Potoos aren’t the most musical or birds, but they are loud – they make harsh, guttural “bwa-bwa-bwa” calls, similar to laughing or wailing. They can also make drawn out, descending rasps, that are… somewhat more musical at least. They tend to make their sounds mostly at dusk, right before dawn, and also on moonlit nights – so when it is Dark, but not too dark. These sounds, of course, do vary from species to species. There are some courtship calls, including descended calls made by females during the mating ritual, but they aren’t a major feature of these events. So, instead of picturing the great wolves as your moonlight singers, remember: the Potoos can and WILL be making these weird urts, laughs, and whistles, every time the moon is full and out in the sky. Potoos do not migrate, but they do appear to move sporadically in response to season changes and mating territory disturbances. 

Long-Tailed Potoo by Lee R. Berger, CC BY-SA 3.0

As for nesting, Potoos are not… fantastic at the prospect, because of their tiny legs and weird, weird beaks. This makes them not great at both sitting on the nest and feeding the chicks. Still, they do it anyway, and clearly well enough since they aren’t endangered with extinction. They are monogamous, with both parents working together to incubate the egg and raise the chick, and they don’t build a nest – instead, the egg is laid in a depression on the branch, usually on top of a rotting stump. The male incubates the egg during the day, while the female will do so with the male at night. The chick is hidden almost entirely through camouflage. They hatch about a month later, and then stay in the nest for two more months, being protected by the parents and fed by them as well. They look… like clumps of fungus. Hiding underneath the log of their parents. The parents will defend themselves and the nest with mobbing behavior, crowding a predator and dive bombing it, and also calling at it loudly. In short, these birds are a Giant, Giant mess of Chaos. 

White-Winged Potoo by Mark Sutton

Ecosystem: Potoos are known primarily from rainforests, and can be found at any level of the forest – some Potoos are known from the understorey, some from the middle, and some from the canopy – it really depends. They’re also found in very swampy forests, depending on the species and the habitats in question. They tend to stick to where there are easily accessible sources of water, regardless, especially rivers and lakes in the jungle. They stick to the deep interior of the forest, not venturing to forest edges much unless driven to by necessity. Some species are also found in mountain forest habitats. They have few natural predators after reaching adult size, though the young are hunted upon by monkeys and falcons. 

Andean Potoo by Isirvio, CC BY-SA 2.0

Other: Potoos are a part of the Stirsorians, a group of WEIRD BIRDS that are adapted for a variety of extremely unique ecological niches, usually depending on their flight style. Close relatives of the Potoo include the Frogmouth, Nightjars, Oilbirds, Swifts, and Hummingbirds, among others. Potoos are highly adapted for their nocturnal lifestyle, adapted to blend in with their forested surroundings above all else. None are threatened with extinction at this time, though of course some species are rarer than others, and all are vulnerable to climate change and extensive habitat destruction in the American Rainforests. They are also quite uncommon birds, which of course affects their vulnerability as well.

Northern Potoo by Dominic Sherony, CC BY-SA 2.0

Species Differences: The different species of Potoo vary mainly on size, coloration, habitat, and location. The Rufous Potoo is one of the most notable, being very red in color and also the smallest species; it is known from northern Amazonia, in the middle and lower storeys of the forest. Great Potoos are the heaviest species, and greyish to yellowish brown; they are found in the canopy of Amazonia. The Long-Tailed Potoo is the longest species, and is a darker brown; it is found in lowland forest in Amazonia. The White-Winged Potoo has – you guessed it – white wings, and is small in size; it is found in the canopy of lowland Amazonia rainforest. The Andean Potoo is very dark and Extremely Muppety, and is found in mountain forests in the Andes Mountains. The Common Potoo is the most middle brown of them all and very middle in size, so the Averagest Potoo of them All; it is found in wet open woodland, usually at forest edges and the canopy, throughout Northern South America. The Northern Potoo is similar to the Common Potoo but usually larger, and it is also found in forest edges, but in Central America and the Carribean. 

~ By Meig Dickson 

Sources Under the Cut 

Microchera albocoronata

By Joseph C. Boone, CC BY-SA 3.0

Etymology: Small Widow

First Described By: Gould, 1858 

Classification: Dinosauromorpha, Dinosauriformes, Dracohors, Dinosauria, Saurischia, Eusaurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Coelurosauria, Tyrannoraptora, Maniraptoromorpha, Maniraptoriformes, Maniraptora, Pennaraptora, Paraves, Eumaniraptora, Averaptora, Avialae, Euavialae, Avebrevicauda, Pygostaylia, Ornithothoraces, Euornithes, Ornithuromorpha, Ornithurae, Neornithes, Neognathae, Neoaves, Strisores, Daedalornithes, Apodiformes, Trochilidae, Trochilinae 

Status: Extant, Least Concern 

Time and Place: Since 10,000 years ago, in the Holocene of the Quaternary 

Snowcaps are known primarily from Central America 

Physical Description: Snowcaps are very small birds – being hummingbirds! They range between 6 and 6.5 centimeters in length, making them only a tad bigger than the smallest dinosaurs of all, the Bee Hummingbirds! All sexes are iridescent – brilliantly shiny and colorful. The males are red, with black wings and a black face; while the females are green and blue with red tails, black wings, and white bellies. They have long, narrow, pointed beaks, that are black in color. They, like other hummingbirds, have very tiny feet, that are rarely used. Their wings are short and triangular, built for hovering, as in all other Hummingbirds. They are named for the white patches on the foreheads of the males! 

Diet: Like other hummingbirds, they primarily eat nectar – specifically the nectar of small flowers on trees and shrubs. They will supplement their diet with insects as well. 

By Andy Reago & Chrissy McClarren, CC BY 2.0

Behavior: Snowcaps spend most of their time hovering around flowers, staying aloft in the air in order to reach into the flower with their beaks and pull out nectar. Males will often defend their food very territorial, but it will run away from larger hummingbirds. They make very soft, warbling melodies, as well as more high-pitched zipping and buzzy noises when fighting each other. They do not tend to migrate, but will go up and down from highlands to lowlands depending on the breeding or nonbreeding season. They tend to breed during the early wet season or late dry season, with the males singing soft warbles on the forest edge to attract mates. They make tiny cups of tree-fern scales, using moss and lichen to bind up the cup – which is hung a few meters up into the tree. Two eggs are laid in the clutch, and the female does most of the incubation for about two weeks. She then feeds the young regurgitated nectar. 

Ecosystem: Snowcap hummingbirds live on forest edges and in tropical rainforest, frequenting the canopy and subcanopy (when male) and the understory when female. They rarely ascend into higher elevations. 

Other: These hummingbirds are not threatened with extinction, remaining very common throughout its range even though deforestation affects some habitats. 

~ By Meig Dickson

Sources Under the Cut 

Jobling, J. A. 2010. The Helm Dictionary of Scientific Bird Names. Christopher Helm Publishing, A&C Black Publishers Ltd, London. 

Kistler, Ethan; Schulenberg, Thomas S (2013). “Snowcap (Microchera albocoronata)”. Neotropical Birds Online. Ithaca: Cornell Lab of Ornithology. 

Stiles, F.G. & Kirwan, G.M. (2019). Snowcap (Microchera albocoronata). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. 

Eurotrochilus

By Scott Reid

Etymology: European Hummingbird 

First Described By: Mayr, 2004 

Classification: Dinosauromorpha, Dinosauriformes, Dracohors, Dinosauria, Saurischia, Eusaurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Coelurosauria, Tyrannoraptora, Maniraptoromorpha, Maniraptoriformes, Maniraptora, Pennaraptora, Paraves, Eumaniraptora, Averaptora, Avialae, Euavialae, Avebrevicauda, Pygostaylia, Ornithothoraces, Euornithes, Ornithuromorpha, Ornithurae, Neornithes, Neognathae, Neoaves, Strisores, Daedalornithes, Apodiformes, Trochilidae 

Referred Species: E. inexpectatus, E. noniewiczi 

Status: Extinct 

Time and Place: Between 31 and 28 million years ago, in the Rupelian of the Oligocene 

Eurotrochilus is known from the Menilite Formation, the Bott-Eder Grube Unterfeld, and Le Grand Banc locations across Poland, Germany, and France 

Physical Description: Eurotrochilus is a bird that is remarkable precisely because, to us, it is utterly unremarkable. Put in a clearer way, Eurotrochilus is almost identical to living Hummingbirds – but it’s thirty million years old. An extremely small bird, Eurotrochilus had wings shaped like hummingbirds – small, triangular, and built for hovering flight. It was about nine centimeters in length, making it as big as living hummingbirds like the Ruby-Throated Hummingbird. In addition to having small, triangular wings, Eurotrochilus had tiny legs, like living Hummingbirds, and a very long beak. So, its identical nature to living hummingbirds points to the hummingbird body plan as an ancient one, that hasn’t been improved upon much during the Cenozoic era. Still, it wasn’t a true hummingbird yet – aka in the group that contains modern hummingbirds and those more closely related to one sort than the other – because it still had long finger bones, and smaller connections between those bones. So, while the general hummingbird shape was present for thirty million years, it still had some modifications left to go. 

Diet: With its very long, specialized bill, Eurotrochilus would have fed on nectar, like living hummingbirds. 

Behavior: We can be fairly confident that Eurotrochilus was capable of hovering, and did so with some regularity; it would hover near flowers and rarely perch on them while gathering nectar up with its long beak. The beak would go into the center of the flower to draw up nectar, and in the process Eurotrochilus would pick up pollen. Then, upon going to the next flower to drink more nectar, Eurotrochilus would drop off the pollen, thus helping the flowers to reproduce. It would have spent most of its time hovering, and when not hovering would rest on branches or in more foliage-filled areas. It would have been a fairly active animal, and loud as well, making a variety of chirps and calls to one another. They probably would have been very brightly colored, like living hummingbirds, and the males probably wouldn’t have been very involved in nest care. 

By Ripley Cook

Ecosystem: Eurotrochilus primarily lived in forested areas, near lagoons, lakes, and estruary-filled areas. These lush habitats were filled with a variety of flowering plants for Eurotrochilus to feed on, and the forests were densely populated with birches, oaks, cypresses, conifers, palms, roses, asterids, and beeches. Eurotrochilus was a common site in these environments, which featured a variety of birds that resembled living forms and yet, were not quite like their modern counterparts. In the Bott-Eder environment of Germany, a coastal bay area, Eurotrochilus lived with birds such as the barbet Rupelramphastoides, the buttonquail Turnipax, the tody Palaeotodus, the mousebird Oligocolius, the trogon Primotrogon, the loon Colymboides, the seabird Rueplornis, and the songbird Wieslochia. This is a notable environment with a variety of transitional tree and ocean going birds, making it a fascinating habitat in which to study the evolution of dinosaurs in the Cenozoic. There were also sea cows, bats, and a Hyaenodont Apterodon, though Eurotrochilus would have been so small its unlikely that the Hyaenodont would have posed a problem for it. In the dense lake environment of Menilite, Eurotrochilus lived with the passerines Jamna, Resoviaornis, and Winnicavis, as well as the woodpecker Picavus. Here there was an extensive amount of thermal activity, which would negatively affect the ecosystem with gas bubbles and oil wells. In the lagoon environment of Le Grand, there was also Primotrogon, the early cuckoo Eocuculus, the crane Parvigrus, and the stem-passerine Zygodactylus. 

Other: As the oldest representative of a proper, nectar-eating hummingbird shape, Eurotrochilus is vital for our understanding of the evolution of hummingbirds. In fact, its presence points to the idea that flowers pollinated by birds co-evolved with hummingbirds in the Eastern Hemisphere, even though hummingbirds aren’t present on that side of the globe today. Hummingbirds like Eurotrochilus, however, disappeared from that half of the globe during tropical climate collapse in Europe and the effects of the ice age. Interestingly enough, they were replaced in the Eastern Hemisphere by Sunbirds, a group of passerines that convergently evolved similar adaptations for hovering and nectar-eating, and also brightly colored feathers. 

Species Differences: The two species of Eurotrochilus mainly differ on the proportions of the limbs, with E. noniewiczi having longer upper arm bones than E. inexpecatus, but shorter lower arm bones. They lived at the same time and fairly close to each other, so this difference is important in telling apart the varying kinds of these early hummingbirds. 

~ By Meig Dickson

Sources Under the Cut 

Sephanoides

Juan Fernández Firecrown by Héctor Gutiérrez Guzmán, CC BY 2.0

Etymology: Resembling a Diadem

First Described By: Gray, 1840

Classification: Dinosauromorpha, Dinosauriformes, Dracohors, Dinosauria, Saurischia, Eusaurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Coelurosauria, Tyrannoraptora, Maniraptoromorpha, Maniraptoriformes, Maniraptora, Pennaraptora, Paraves, Eumaniraptora, Averaptora, Avialae, Euavialae, Avebrevicauda, Pygostaylia, Ornithothoraces, Euornithes, Ornithuromorpha, Ornithurae, Neornithes, Neognathae, Neoaves, Strisores, Daedalornithes, Apodiformes, Trochilidae, Trochilinae  

Referred Species: S. sephaniodes (Green-Backed Firecrown), S. fernandensis (Juan Fernández Firecrown)

Status: Extant, Critically Endangered – Least Concern

Time and Place: Within the last 10,000 years, in the Holocene of the Quaternary 

The Firecrowns live in southern South America, as well as Isla Robinson Crusoe 

Physical Description: Firecrown Hummingbirds are distinctive for the reason you would indeed expect – their fiery heads! Both species have fancy feathers on their foreheads. Like all hummingbirds, these are quite small – ranging from 10 to 12 centimeters in length. The males generally have reddish coloration, while the females are more greenish. A lot of the differences between the sexes are species-based, however, and can be found in that section of this article. Like other hummingbirds they have long, thin, grey bills, and very long fluffy tails. Their wings are small and triangular for hovering. .

Diet: The Firecrowns are nectivores, feeding on a variety of flower nectar that they glean with their long beaks. They hover in order to stay near on a flower for a long time, in order to get enough food. The Juan Fernández species will also eat insects, especially during the chick rearing season. 

Green-Backed Firecrown by Suemili, CC BY-SA 3.0

Behavior: These birds make songs of high-pitched, squeaky notes, and dry trills, as well as descending chatters. The Green-Backed Firecrown does migrate, wintering in the lowlands of Argentina, and moving back up to the north during the summer. The Juan Fernández species does not migrate.

These birds breed from September through November, making very small cup-shaped nests containing two white eggs. These nests can either be found in cover or over water. Very little else is known of their breeding behavior, though homosexual activity between males has been documented in this species. 

Green-Backed Firecrown by Felipe Bernala, CC BY

Ecosystem: The Firecrowns live in thick jungles and rainforests, usually at mid levels of vegetation; they can also be found in large numbers wherever trees are flowering (for fairly obvious reasons). They can be found near human-created habitats as well. The Juan Fernández Firecrown have their nests preyed upon by Austral Thrushes.

Other: The Green-Backed Firecrown is very common and is threatened currently by man-made environmental pressures; the Juan Fernández Firecrown is critically endangered, with a population of less than 2000 mature individuals. They seem to be threatened due to human activity, especially plant destruction, habitat disturbance, wood harvesting, introduced mammal predators and competitors, and other terrifying environmental distressors. Direct conservation actions are ongoing, and there are talks of breeding programs. 

Juan Fernández Firecrown Arthur Grosset, CC BY-SA 3.0

Species Differences: The Green-Backed Firecrown is smaller than the Juan Fernández species, and it is also green all over its body in both sexes. Their wings are grey, and the major difference between males and females is that the males have iridescent orange crowns on their heads. The Juan Fernández Firecrown has completely orange males, with iridescent crowns; the females are green backed, with blue tails and blue iridescent crowns. They also have grey wings in both sexes. The Green-Backed Firecrown lives on the mainland of South America, while the Juan Fernández Firecrown is only found on Isla Robinson Crusoe.

~ By Meig Dickson

Sources under the Cut 

Fluvioviridavis platyrhamphus

By Ripley Cook

Etymology: Green River Bird

First Described By: Mayr & Daniels, 2001

Classification: Dinosauromorpha, Dinosauriformes, Dracohors, Dinosauria, Saurischia, Eusaurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Coelurosauria, Tyrannoraptora, Maniraptoromorpha, Maniraptoriformes, Maniraptora, Pennaraptora, Paraves, Eumaniraptora, Averaptora, Avialae, Euavialae, Avebrevicauda, Pygostaylia, Ornithothoraces, Euornithes, Ornithuromorpha, Ornithurae, Neornithes, Neognathae, Neoaves, Strisores, Podargiformes

Status: Extinct

Time and Place: Between 53.5 and 48.5 million years ago, in the Ypresian of the Eocene of the Paleogene 

Fluvioviridavis is known from the Fossil Butte Member of the Green River Formation of Wyoming 

Physical Description: Fluvioviridavis was a stem-frogmouth, and looked nearly like a modern one when you get right down to it – it had a normal sized head with a huge triangular beak attached to it, a fairly round body, long wings, and short legs, so that it would have looked very squat in life. In addition to looking very squat, it would have also been able to compact its neck so that it could look even more squat – giving it a very long neck tucked up tight inside its throat. Its beak, though wide and flattened like modern frogmouths, is still fairly narrow and more pointed than living members of the group, making it distinctly different from its modern relatives.

Diet: Like modern frogmouths, Fluvioviridavis probably ate small to medium sized animals, especially insects, small mammals, reptiles, frogs, and even possibly smaller birds. 

By Scott Reid

Behavior: Like its modern relatives, Fluvioviridavis probably spent most of its time sitting on trees, scrunched up to blend in with the trees around it. It would remain motionless, so prey wouldn’t notice it as it watched from above. Then it would divebomb food, catching it on the ground before it even knew what was happening. In addition to this, Fluvioviridavis probably would catch flies in mid-air, diving them rapidly to catch them in their ridiculous mouths.

Fluvioviridavis would have been a more aerial bird than living frogmouths, spending most of its time in the air catching food there, even though it would have been entirely capable of perching as per its feet. Though, fascinatingly enough, if Fluvioviridavis is a stem-frogmouth as is assumed, it showcases an early stage in the evolution of perching in this group, still having claws and other features in its feet later lost by the group as a whole. Still, the general weird shape of the Frogmouths evolved very early in the Frogmouth lineage.

Fluvioviridavis, being a bird, probably took care of its young; though other social characteristics of this species are unknown. It’s possible it was something of a loner, since it isn’t the most common of fossils in an environment known for having an abundance of bird fossils. 

By José Carlos Cortés

Ecosystem: The Green River Environment was just one of many very well preserved ecosystems from the Global Rainforest of the early Eocene – being older than the Messel Pit, it showcases very distinctive creatures. This environment was a fossil lake scattered amongst the jungle, with only moderately dense vegetation compared to, say, Europe. The lake was dominated by sycamore trees, as well as ferns, palms, and other kinds of trees and flowers. This was an environment greatly affected by the forming of the Rocky Mountains, which lead to rapid influxes of nutrients – overwhelming the lakes and suffocating the fish inside. This lead to unique preservation, and a wide variety of food for Fluvioviridavis to feed on. There were a lot of different kinds of dinosaurs there, including the Lithornithids Pseudocrypturus and Calciavis; the flamingo-duck Presbyornis; the early pheasant Gallinuloides; the early swift and hummingbird relative Eocypselus; another frogmouth relative, Prefica; an early mousebird, Anneavis; the early woodpecker Neanis; parrots of prey such as Cyrilavis and Tynskya; and some of the earliest passerines, Zygodactylus and Eozygodactlyus – with all of the animals showcasing the explosion of Neoavians after the end-Cretaceous Extinction. There were also mammals such as early primates, bats, and armadillos; crocodilians like Borealosuchus; and a variety of rays, catfish, suckers, herrings, and sardines.

Other: It is possible that Fluvioviridavis wasn’t actually a stem-frogmouth at all, but an unrelated strisorian that explored the frogmouth niche before frogmouths came along. More research is needed to figure this out, but regardless, Fluvioviridavis showcases an interesting step in early bird evolution after the end-Cretaceous extinction! This bird might have also spread to the London Clay Environment across the sea, but that’s not been confirmed yet.

~ By Meig Dickson

Sources under the Cut 

Calothorax

Lucifer Hummingbird by Greg Schechter, CC BY 2.0

Etymology: Beautiful Breast

First Described By: Gould, 1859

Classification: Dinosauromorpha, Dinosauriformes, Dracohors, Dinosauria, Saurischia, Eusaurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Coelurosauria, Tyrannoraptora, Maniraptoromorpha, Maniraptoriformes, Maniraptora, Pennaraptora, Paraves, Eumaniraptora, Averaptora, Avialae, Euavialae, Avebrevicauda, Pygostaylia, Ornithothoraces, Euornithes, Ornithuromorpha, Ornithurae, Neornithes, Neognathae, Neoaves, Strisores, Daedalornithes, Apodiformes, Trochilidae, Trochilinae  

Referred Species: C. pulcher (Beautiful Hummingbird), C. lucifer (Lucifer Hummingbird)

Status: Extant, Least Concern

Time and Place: Within the last 10,000 years, in the Holocene of the Quaternary 

The Lucifer and Beautiful Hummingbirds are known entirely from Mexico, though the Lucifer Hummingbird does creep into the southwestern corner of the United States 

Physical Description: Calothorax is a genus of hummingbirds, small dinosaurs that essentially convergently with insects. Calothorax ranges from 8 to 10 centimeters in length. Like most Hummingbirds, it has an ovular body, a small head, and a very long, skinny bill. The bodies of Calothorax are green in both sexes. The males have bright purple patches on their throats, while the females have orange splotches across their bellies and under their wings. Both have white patches along their throats and breasts. The females also have generally shorter bills. They have short, triangular wings for hovering, and tiny tail feathers. 

Beautiful Hummingbird by Michael Retter

Diet: Like most hummingbirds, Calothorax feeds on nectar taken from flowers such as the Penstemon, Sierra Woolly Indian Paintbrush, Big Bend Anisacanthus, Yellow-Flowered Century Plant, and a variety of other flowers from cacti, grasses, and brushes. They do supplement their diet with flies.

Behavior: These birds hover near sources of nectar and use their long beaks to reach into the petals of the flower. They move their wings so fast that they are able to over, an ability that birds are not usually able to achieve. This also means that they have very strong chest muscles and extremely rapidly pumping hearts to help power this high-intensity movement. These birds make repeated, high-pitched squeaky tweets, as well as faint chirps and rattles. The wings themselves make hums like the wings of bees while they hover. 

Lucifer Sheartail by Geoff Gallic, CC BY 2.0

The males, when wanting to mate with a female, will move back and forth in a horizontal hovering line. He then goes high up, before diving suddenly before her. The male then spreads his forked tail, making wacky calls to attract her. These birds breed from April through August, starting the breeding season later in the year the farther south they live. They tend to group their nests together, placing them on rocky slopes near streams, and built out of river-associated plants. They lay two small, white eggs, which are incubated by the female for two weeks, before spending three more weeks in the nest. The young birds then stay near the mother for three more weeks, where they can still be fed by the mother.

The Lucifer Hummingbird move across Mexico and into the United States based on the change of the dry and wet season, though some do remain in one spot. The Beautiful Hummingbird does not migrate.

Ecosystem: These birds live in arid and tropical scrub forest, usually at fairly higher elevations. 

Lucifer Hummingbird by Caleb Putnam, CC BY 2.0

Other: These birds are not threatened due to a large range of foraging and breeding habitats, though the Beautiful Hummingbird is not as well known as the Lucifer Hummingbird.

Species Differences: The Lucifer and Beautiful Hummingbirds are virtually identical, and mainly differ in that the Lucifer Hummingbird is on average larger than the Beautiful Hummingbird – by a single centimeter – and also has a significantly larger range. Not to mention, the Beautiful Hummingbird remains confined in southern Mexico, while the Lucifer Hummingbird migrates from southern Mexico in the winter to northern Mexico and the southwestern United States in the summer.

~ By Meig Dickson

Sources 

Jobling, J. A. 2010. The Helm Dictionary of Scientific Bird Names. Christopher Helm Publishing, A&C Black Publishers Ltd, London.

Prum, R.O. et al. 2015. A comprehensive phylogeny of birds (Aves) using targeted next-generation DNA sequencing. Nature 526: 569–573.

Scott, P.E. & Boesman, P. (2019). Beautiful Hummingbird (Calothorax pulcher). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.

Scott, P.E. & Boesman, P. (2019). Lucifer Hummingbird (Calothorax lucifer). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.