Every year, researchers describe new species of animals and plants, from forests and oceans, after months, or even several years, of trials and tribulations.

In 2018, Mongabay covered many of these new discoveries and descriptions, some a result of chance encounters.

In no particular order, we present our 10 top picks.

Once again this year, researchers described several new species of animals and plants after months, or even several years, of trials and tribulations. Some were tiny, like the Japan pig, a colorful pygmy horse that’s smaller than a fingernail. Some were cases of mistaken identities, such as Africa’s biggest cobra that turned out to be not one but five species. Some, like the new species of giant salamander, took nearly a decade to capture and describe. Other species, although new to science, such as the stunning blue-throated hillstar, are already severely threatened and could become extinct before we get the chance to learn more about them.

In 2018, Mongabay covered many of these new discoveries and descriptions. Below, in no particular order, we present our 10 top picks.

The forest cobra, Africa’s biggest true cobra, which was considered to be a single species for a long time, is actually five distinct species, a study published this year found. Two of these species, the black forest cobra (Naja guineensis) and the West African banded cobra (N. savannula), are in fact new to science.

As a single species, forest cobras were not considered threatened because the loss of a few populations wasn’t seen as a major cause for concern. But with the splitting of the cobra into five species, some species could be more vulnerable to forest loss and extinction than others. The Central African forest cobra (N. melanoleuca) and the brown forest cobra (N. subfulva) have wide distributions, for example, but the black forest cobra is under greater threat, researchers say, since its distribution is limited to the Upper Guinean forests of West Africa that have suffered severe deforestation. The West African banded cobra and the São Tomé forest cobra (N. peroescobari) are also of considerable concern.

This new species of salamander, 60 centimeters (2 feet) long, was described after more than a decade of surveys and explorations. Named the reticulated siren (Siren reticulata) after the dark spots that run in a reticulated pattern on the animal’s body, extending from the gills to the tail, the salamander was earlier (informally and incorrectly) called the “leopard eel.” Ecologist David A. Steen caught his first reticulated siren in a trap meant for turtles in Florida in 2009. But it was only in 2014 when, with a colleague, he managed to collect four more individuals. It then took another four years for the pair to analyze and describe the salamander as a new species of siren, a group of eel-like salamanders that have only front limbs and large, frilled gills poking out of their bodies, behind their heads.

The newly described Groves’s dwarf lemur (Cheirogaleus grovesi), which is smaller than a squirrel, was discovered in both Ranomafana and Andringitra national parks in Madagascar. Researchers have named the species for British-Australian biological anthropologist and primate taxonomist Colin Groves, who died last year. Since the species is known from two parks that are connected by a protected wildlife corridor, researchers believe it may not be as threatened as some other lemur species that occur outside of protected areas. But deforestation, which is widespread across Madagascar, could threaten the new species’ status. Moreover, the researchers are unsure if the new lemur species is hunted by the local communities for bushmeat, but say “this is certainly a possibility.”

Off the coast of southeast Japan, researchers discovered a species of pygmy seahorse that’s smaller than the average fingernail. The tiny seahorse has a paisley pattern that helps it camouflage well against the corals and rocks it lives on. The new species has been named the Japan pig, or Hippocampus japapigu, because of its apparent resemblance to a tiny baby pig, researchers say. While the species was described in a paper this year, Japanese scuba divers had observed the pygmy seahorse for many years in the waters off southeast Japan. In fact, researchers believe the seahorse could have a much wider distribution than is currently known.

Seventy years ago, in a forest high up in the Bamenda highlands of Cameroon, a Nigerian forester named Edwin Ujor collected a specimen of an unknown tree. This year, scientists formally described the Ujor specimen as a new species, and named it Vepris bali. Known from just a single location in Bali Ngemba Forest Reserve, an officially protected block of cloud forest near the highland town of Bali, the species is likely critically endangered. In fact, it may already be extinct, given that the higher-altitude regions from which the Ujor specimen was collected have since been largely cleared for agriculture.

Ornithologists described this stunning new-to-science species of hummingbird from Ecuador’s southwestern highlands. Named the blue-throated hillstar, or Oreotrochilus cyanolaemus, after its glittering ultramarine-blue chin and throat feathers, the hummingbird lives on grasslands on the Ecuadoran Andes, a habitat that’s being rapidly lost to farmlands, pasture, pine plantations and gold mining. Researchers believe the bird is likely already critically endangered and they are working with local communities to protect the species.

This year, researchers from the California Academy of Sciences (CAS) described 17 new species of Hypselodoris, a genus of colorful sea slugs that live among coral reefs in the Indo-Pacific region. These include H. confetti, which looks like it’s covered in shreds of brightly colored paper, and H. rositoi, named for its distinctive rose-pink shade. The researchers also reorganized the species within Hypselodoris using genetic tools and found clues to why the sea slugs are so colorful. So far, none of the newly described species seem to be at any immediate risk of extinction, but the team says that with climate change impacting the oceans and coral reefs, the slugs’ conservation status could change quickly.

For a long time, researchers thought that the rainforests of New Guinea were home to a single species of the superb bird-of-paradise, the bird with the now-famous “smiley face” dance routine. This year, however, a team of scientists confirmed that there was a second species of the superb bird-of-paradise in the Indonesian Bird’s Head, or Vogelkop, region of the island. The Vogelkop superb bird-of-paradise (Lophorina niedda) differs from the superb bird-of-paradise in many ways: males of both species have very different dance moves, and when the male Vogelkop superb bird-of-paradise is ready to woo a female, it spreads out its black cape into a crescent shape, its iridescent blue breast feathers giving the bird a “frowning face” look, in contrast to the smiley face of the male greater superb bird-of-paradise. The calls of the males also differ between the species, as does the appearance of the females.

The newly described Palawan moss shrew, or Palawanosorex muscorum, is known to live only near the top of Mount Mantalingajan, the highest mountain on Palawan Island in the southern Philippines. In fact, the tiny, gray shrew has been spotted only in forests close to the peak of the 2,086-meter (6,844-foot) mountain, and is one of three mammal species known to occur only on Mantalingajan. Much of the Palawan moss shrew’s habitat is currently undisturbed by human activity, and the researchers hope it will stay this way.

This discovery was a completely chance encounter: A team of biologists studying sea snakes in the mining town of Weipa in Australia’s remote Cape York Peninsula spotted a small black-and-white snake on a concrete block by the sea. The snake, it turned out, was a new-to-science species of bandy-bandy, a group of snakes that live in burrows and feed on a specialized diet of blind snakes. The new species, now named the Cape York bandy-bandy, or Vermicella parscauda, lives in an area that has large-scale bauxite mining, which involves extensive digging, researchers say. Mining activities could be affecting the naturally burrowing bandy-bandy, they add.