Tag: Pacific

Unusual new zoantharian species is the first described solitary species in over 100 years

A very unusual new species of zoantharian surprised Drs Takuma Fujii and James Davis Reimer, affiliated with Kagoshima University and University of the Ryukyus.

The scientists stumbled upon a solitary individual polyp while conducting SCUBA surveys around the southern Japanese island of Okinawa. They noticed that the creatures were buried almost completely in the soft sediment of the seafloor. It was only their oral disks and tentacles that were protruding above the surface.

Generally, most known zoantharians are colonial (hence their common name of ‘colonial anemones’), and many dwell in shallow waters of subtropical and tropical regions, where their large colonies can be found on coral reefs.

However, these newly discovered polyps were not only leading solitary lives. They were also found to lack zooxanthellae, single-celled organisms that coexist in symbiosis with certain marine invertebrates, also typical for the majority of zoantharians.

The discovery of this unusual new species is reported in the open access journal ZooKeys.

Solitary zoantharian species, such as this one, are known from scant few reports, and only three species are described, all reported more than 100 years ago from the Indo-Pacific region. Overall, very little is known about the hereby studied genus Sphenopus.

The new species, named Sphenopus exilis, is much smaller than the other three Sphenopus species, with its polyps measuring approximately 3 cm in length. It is currently only known from two bays on the east coast of Okinawa Island.

Both of the bays where Sphenopus exilis is found are threatened by development, with one of the bays currently the center of controversy over a proposed American military base expansion and landfill.

“This report demonstrates how much more research is needed on these understudied ecosystems”, stated lead author Dr. Takuma Fujii.

“The only reason this species was discovered was that the right person was in the right place at the right time”, added co-author Dr. James Reimer.

“Such research also shows how important it is to have specialist researchers participate in surveys — otherwise, we might be missing a lot of the biodiversity present in the marine realm simply because we don’t know what we are looking at,” he concluded.

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Original source:

Fujii T, Reimer JD (2016) A new solitary free-living species of the genus Sphenopus (Cnidaria, Anthozoa, Zoantharia, Sphenopidae) from Okinawa-jima Island, Japan. ZooKeys 606: 11-24. doi: 10.3897/zookeys.606.9310

The Castaway: New monitor lizard fills top-order predator role on remote Pacific island

Separated by several hundred kilometres from its next of kin, a new species of blue-tailed monitor lizard unique to the remote Mussau Island has been described. Unknown to science until recently and formally termed the “isolated”, it is the only large-sized land-living predator and scavenger native to the island.

Dubbed a “biogeographical oddity” by its discoverers, led by Valter Weijola, a graduate student from the University of Turku, Finland, the lizard species is also the first new monitor lizard to be described from the country of Papua New Guinea in over twenty years. The finding was published in the open-access journal ZooKeys.

Monitors play an important ecological role in many island ecosystems in the southwest Pacific. Predatory mammals have never colonized the region due to the isolation of these islands. Instead, these large, active and intelligent lizards fill the role of top-predators and scavengers. The Pacific monitor lineage to which the new species belongs have been so successful at oversea dispersal that a number of different species now occupy almost every island from the Moluccas in Indonesia to the eastern Solomon Islands and even Micronesia.

The new endemic species was observed and studied during fieldwork by Weijola and local assistants in the relatively dry coastal vegetation of Mussau, but it is likely that it also persist in the remnants of intact forest in the interior of the island.

The formally described female lizard, or holotype, measures 1 m with the tail being one and and a half times the length of the dominantly black-coloured body covered with yellow and orange markings. The tail of the adults shows varying degrees of turquoise to bluish pigmentation. Another distinctive feature for the species is the pale yellow tongue, which is a trait shared only by three other species of Pacific monitors. The new species is known to eat crabs, other reptiles and their eggs, and small birds.

“Usually monitors like these will eat just about anything they can catch and kill, as well as carcass and turtle eggs when available,” explains Weijola. “While young, Pacific monitor lizards are highly secretive and subsist mainly on insects and other small animals.”

The new species, which can grow to well over a meter in length, was named Varanus semotus, a Latin reference to the remoteness and isolation of the relatively small and partly volcanic island where the lizard was found. Close examination revealed the reptile to be distinct from its relatives from New Guinea and New Britain. Genetic studies, conducted by co-authors Stephen Donnellan, South-Australian Museum, and Christer Lindqvist, Åbo Akademi University, showed that the species has been isolated for a long time, estimatedly 1-2 million years, or even longer.

“Isolation is the keyword here,” says Weijola. “It is what has driven speciation and made the South-Pacific region one of the World’s biodiversity hotspots.” For anything to arrive on Mussau (from New Guinea or New Britain) it would need to cross 250-350 kilometers of open sea, and this doesn’t happen frequently. So, once the ancestor arrived, perhaps in the form of a gravid female, the population must have been completely isolated.””These islands are full of unique creatures often restricted in distribution to just one island or island group,” explains the researcher. “Yet, we know relatively little about them. Even large species of reptiles and mammals are regularly being discovered, not to mention amphibians and invertebrates. This is what makes it such a biologically valuable and fascinating region.”

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Original source:

Weijola V, Donnellan SC, Lindqvist C (2016) A new blue-tailed Monitor lizard (Reptilia, Squamata, Varanus) of the Varanus indicus group from Mussau Island, Papua New Guinea.ZooKeys 568: 129-154. doi: 10.3897/zookeys.568.6872

New snake species with pitch black eyes from the Andes highlights hidden diversity

Extremely rare and hidden in the forests of the Andes, there are still new snake species left to find. This has recently been evidenced by the colubrid serpent, described for the first time in the present article. Moreover, there is the vicious circle enwrapping its relatives: the harder it is to find more specimens, the tougher it is to describe and thus, start to identify them, which does not help in mapping their distribution and habitats. To address this issue, Dr. R. Alexander Pyron, The George Washington University, and his international research team have included a taxonomic review and discussion on the relationships and origin within a non-venomous snake tribe in a paper, published in the open-access journal ZooKeys.

Slender and small, the new species, called Synophis zaheri, measures less than 40 cm in length, or between 351 and 372 mm. Contrasting to its slim body with a distinct neck, separating the head from the body, its eyes are large and bulging, making up for more than a third of its head. Being black in colour, it is hard to tell the pupil and the iris apart. While the upper part of the body is grayish-brown with an iridescent sheen, the abdominal side stands out with its yellowish-white colouration.

Typically for the tribe, where the new species has been placed, it is also characterised with a highly modified spine and an enlarged scale row running over it. This is also where the name of this group of snakes comes from with “Diaphorolepidini” consisting of the Greek words for “differentiated” and “scales”. Not so clear, however, is the name of the genus, which the authors have translated also from Greek as “with snake”, but find themselves unaware of the meaning behind. The species is named after Dr. Hussam El-Dine Zaher, a Brazilian herpetologist whose work has been foundational for South American snakes.

In conclusion, the scientists note that the rarity of the observed snake species, especially the genus, where the new serpent belongs, accounts for the unclear species-boundaries as well as for the myriad of undescribed species. “Dipsadine diversity in the Andes is clearly underestimated, and new species are still being discovered in the 21st century,” they point out.

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Original source:

Pyron RA, Guayasamin JM, Peñafiel N, Bustamante L, Arteaga A (2015) Systematics of Nothopsini (Serpentes, Dipsadidae), with a new species of Synophis from the Pacific Andean slopes of southwestern Ecuador. ZooKeys 541: 109-147. doi: 10.3897/zookeys.541.6058

How to catch a small squid? First records for the Gulf of California and southwest Mexico

Often avoiding sampling gear with their capability to detect movements and swim their way out of the nets fast enough, the small squids living in the open-ocean zone have so long gone under-researched. The present study, conducted by Dr. Michel Hendrickx, Universidad Nacional Autonoma de Mexico, and his team, seems to provide new and first distributional records of five such species for the Gulf of California and in southwestern Mexico. It also significantly expands the currently known southernmost limit of localities of some of these squids in the eastern Pacific. The research is available in the open-access journal ZooKeys.

The researched five squid species belong to two genera, Abraliopsis and Pterygioteuthis, which although abundant and diverse, have long been shrouded by taxonomic and distributional controversies. To solve them, the researchers used specimens, collected over the span of thirteen years, comprising eight cruises across 113 locations in the Gulf of California and off the southwestern coast of Mexico.

As a result, the scientists concluded a significantly wider distributional range of the species they found. For instance, squids of the Abraliopsis genus were surprisingly found in water deeper than 600 m during the day.

The studied small squids are of high ecological value due to their vital position in the food web. Members of Abraliopsis are important preys for many fishes and mammals, such as the peruvian hake, the Indo-Pacific sailfish, the common dolphinfish and the local sharks. Meanwhile, the representatives of the other researched genus, Pterygioteuthis, are often consumed by larger cephalopods, sea-birds and fur seals. However, their abundance is strongly dependent on temperature, especially when there are fast and significant changes.

The scientists suggest that additional samplings with more adequate equipment, like faster large-sized mid-water trawls, could further bridge the knowledge gaps about these elusive marine inhabitants.

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Original source:

Hendrickx ME, Urbano B, Zamorano P (2015) Distribution of pelagic squids Abraliopsis Joubin, 1896 (Enoploteuthidae) and Pterygioteuthis P. Fischer, 1896 (Pyroteuthidae) (Cephalopoda, Decapodiformes, Oegopsida) in the Mexican Pacific. ZooKeys 537: 51-64. doi: 10.3897/zookeys.537.6023.