Tag Archives: Galápagos Islands

Acalypha flaccida Hook. f.

Flaccid Copperleaf (Acalypha flaccida)

The Flaccid Copperleaf is known only from the type material that was collected in the middle of the 19th century on Isla Santiago, Galápagos Islands by Charles Darwin himself.

The species is, or maybe was, an erect annual herb with hirsute stems and about 2 to 4 cm long and 1,5 to 3 cm wide leaves. [1]

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References:  

[1] I. Loren Wiggins; D. M. Porter; E. F. Anderson: Flora of the Galápagos Islands. Stanford University Press 1971 

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edited: 11.06.2020

Azurina eupalama Heller & Snodgrass

Galapagos Damsel (Azurina eupalama)

The Galapagos Damsel was, as its name implies, endemic to the Galápagos Islands.

The species was formerly common in localized aggregations in the waters surrounding the islands of Española, Floreana, Isabela, Marchena, San Cristobal, Santa Cruz, Santa Fé, and Santiago but begun to decline in 1983 during a devastating El Niño year and was finally not seen again since.

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Depiction from: ‘Edmund Heller; Robert E. Snodgrass: Papers from the Hopkins Stanford Galapagos Expedition, 1898-1899. XV. New fishes. Proceedings of the Washington Academy of Sciences 5: 189-229. 1903’

(public domain)

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References:

[1] Graham J. Edgar; Stuart A. Banks; Margarita Brandt; Rodrigo H. Bustamantes; Angel Chiriboga; Lauren E. Garske; Peter W. Glynn; Jack S. Grove; Scott Henderson; Cleve P. Hickman; Kathy A. Miller; Fernando Rivera; Gerald M. Wellington: El Niño, grazers and fisheries interact to greatly elevate extinction risk for Galapagos marine species. Global Change Biology 16: 2876-2890. 2010

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edited: 29.11.2018

Naesiotus alethorhytidus (Dall)

Santa Cruz Snail (Naesiotus alethorhytidus)

This species was described in 1917; it was restricted the southern part of Isla Santa Cruz in the Galapágos Islands and was apparently quite common when it was discovered and described.:

Indefatigable Island, in the moist area on the south side at 350 to 400 feet, and at all attitudes in the interior; (W. H. O.)
This almost comically small and wrinkled species is one of the most interesting finds of the Academy expedition. It is usually pink tipped, with white corrugations and the indentations more or less darkened by volcanic dust.
” [1]

The species was last found alive in 1974 and is thus believed to be possibly extinct.

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References:

[1] William Healey Dall; Washington Henry Ochsner: Landshells of the Galapagos Islands. Proceedings of the California Academy of Sciences. Ser. 4. Vol. 17.: 141-185. 1928

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Photo from: ‘William Healey Dall; Washington Henry Ochsner: Landshells of the Galapagos Islands. Proceedings of the California Academy of Sciences. Ser. 4. Vol. 17.: 141-185. 1928’

https://creativecommons.org/licenses/by-nc-sa/3.0/

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edited: 01.06.2021

Acalypha sericea var. baurii (B. L. Rob. & Greenm.) Webster

Baur’s Silky Copperleaf (Acalypha sericea var. baurii)

The Silky Copperleaf (Acalypha sericea Anderss.) is endemic to the Galápagos Islands, where several varieties are found on many of the islands.

This one, discussed here, is apparently restricted to the Isla San Christóbal and is known only from a single collection that was purchased sometimes in the middle of the 19th century. [1]

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References:

[1] I. Loren Wiggins; D. M. Porter; E. F. Anderson: Flora of the Galápagos Islands. Stanford University Press 1971

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edited: 11.06.2020

Naesiotus kublerensis Chambers

Cueva de Kubler Snail (Naesiotus kublerensis)

This species was described in 1986; it is known from subfossil shells that were found amongst a larger collection of shells in the Cueva de Kubler on the island of Santa Cruz in the Galápagos archipelago. [1]

The species was never seen alive and is clearly extinct.

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References:

[1] Steven M. Chambers; David W. Steadman: Holocene terrestrial gastropod faunas from Isla Santa Cruz and Isla Floreana, Galápagos: evidence for late Holocene declines. Transactions of the San Diego Society of Natural History 21(6): 89-110. 1986

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edited: 01.06.2021

Euphorbia equisetiformis Stewart

Equisetiform Spurge (Euphorbia equisetiformis)

This enigmatic species is known only from the type material that was collected on Isla Isabella, Galápagos Islands, it appears not to be related to any other Central- or South American species of its genus.

The species is a leafless, middle-sized shrub with several stems that bear clusters of branches on their upper nodes. [1]

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References:

[1] I. Loren Wiggins; D. M. Porter; E. F. Anderson: Flora of the Galápagos Islands. Stanford University Press 1971

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edited: 11.06.2020

Naesiotus saeronius (Dall)

Saeronius Galapagos Snail (Naesiotus saeronius)

This species was described in 1917, it was restricted to the Isla Santa Cruz in the Galápagos archipelago.

The species was last seen in 1974; it could not be found alive during the last recent searches and might thus be extinct. 

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References: 

[1] William Healey Dall; Washington Henry Ochsner: Landshells of the Galapagos Islands. Proceedings of the California Academy of Sciences. Ser. 4. Vol. 17.: 141-185. 1928  

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edited: 01.06.2021

Nesoryzomys sp. ‘1 Isla Isabela’

Isabela Rice Rat (Nesoryzomys sp.)

This is one of two species of rice rats that formerly were endemic to the Isla Isabela in the Galápagos Islands, it disappeared sometimes during the middle of the 19th to the early 20th century.

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edited: 11.06.2020

Geospiza magnirostris ssp. magnirostris Gould

Large Ground Finch (Geospiza magnirostris ssp. magnirostris)

The Large Ground Finch was described in 1837 based on material that was collected by Charles Darwin on the Galápagos Islands.

The species reaches a size of about 16 cm; the males are mostly blackish brown while the females are speckled dark – and light brown.

Today this species can be found on all the main islands within the archipelago, except for Darwin, Española, and San Cristóbal, where it is thought to have become extinct. 

***

When Charles Darwin visited the Galápagos Islands in 1835, he collected several specimens on several of the islands; his specimens, however, don’t always bear reliable labels, and in some cases, he seems to have forgotten on which island he had collected which specimen.

Indeed, Darwin’s typespecimens have provided a considerable nightmare of taxonomic problems for subsequent ornithologists, based largely on their controversial localities. Darwin claimed, for example, that specimens of a peculiar large-beaked form of Geospiza magnirostris came from Chatham [Isla Floreana] and Charles islands [Isla San Cristóbal]. But after more than a century of subsequent collecting without finding any such large-billed specimens, ornithologists found themselves faced with a puzzle. Either this form had become extinct on Chatham and Charles islands, where no magnirostris specimens (large or small) had ever been found by other expeditions; or else Darwin’s specimens must have come from islands other than those indicated.” [1]

***

This very large-billed Large Ground Finch is often treated as some kind of nominate form of the species but may in fact be nothing but a just large-billed population that is now gone for whatever reasons.

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References:  

[1] Frank J. Sulloway: The Beagle collections of Darwin’s finches (Geospizinae).- Bulletin of the British Museum of Natural History (Zoology) 43: 49-94. 1982

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Depiction from: ‘John Gould: The Zoology of the Voyage of H.M.S. Beagle, under the command of Captain Fitzroy, during the years 1832-1836. Part III, Birds. London, Smith, Elder & Co. 1838’  

(public domain)

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edited: 31.05.2021

Naesiotus sp. ‘krameri’

Kramer’s Galapagos Snail (Naesiotus sp. ‘krameri’)

This species was described in 1985, its species epithet, however, is now considered a nomen nudum, the reasons therefore are not known to me.

Kramer’s Galapagos Snail appears to have been quite common when it was discovered and described, it was found in all wetlands and in the Scalesia forests north of Cerro Puntudo on the island of Santa Cruz, Galápagos Islands. [1]

The species seems to have not been found alive during the most recent field searches and might be extinct.

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References: 

[1] Guy Coppois: Etude de la spéciation chez les Bulimulidae endémiques de l’archipel des Galápagos (Mollusques, Gastéropodes, Pulmonés). Thèse de Doctorat, Libre de Bruxelles 1-283. 1985

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edited: 01.06.2021

Naesiotus achatellinus Forbes

Achatinella-like Galapagos Snail (Naesiotus achatellinus)

The Achatinella-like Galapagos Snail was described in 1850.

There is no doubt that N. achatellinus is one of the rarer Galápagos land snails. It is of special interest because of its superficial resemblance to certain species of Hawaiian tree snails of the genus Achatinella. Also, its straight-sided, conical shape, its non-impressed, nodulose sutures, and its relatively bright color pattern set it apart from any other known species of Naesiotus from the Galápagos Islands or from the South American mainland.” [2]

The species was found first on Island San Cristóbal in the early 1830s and in 1846; in 1868, it was apparently also found on Isla Española.

The shells reach sizes of about 1,2 to 1,6 cm in height, they are: “perforated, ovate-pyramidal with long, conic spire, rather thin; variously colored, being banded with chestnut on an olivaceous or whitish ground, or chestnut below, white above, always with a white line below the suture; surface smooth and glossy, like an Achatinella with slight growth-wrinkles and an impressed band below the suture, pinched up into tubercles at irregular intervals.” [1]

***

The Achatinella-like Galapagos Snail disappeared from Isla Española at an unknown date and was last seen on Isla San Cristóbal in the 1980s; it is now most likely extinct.

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References: 

[1] George W. Tryon; Henry A. Pilsbry; a.o.: Manual of Conchology. Second series: Pulmonata. Vol 11: American Bulimulidae: Bulimulus, Neopetraeus, Oxychona, and South American Drymaeus. 1897-1898
[2] Allyn G. Smith: New record for a rare Galápagos land snail. Nautilus 85(1): 5-8. 1971

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Depiction from: ‘George W. Tryon; Henry A. Pilsbry; a.o.: Manual of Conchology. Second series: Pulmonata. Vol 11: American Bulimulidae: Bulimulus, Neopetraeus, Oxychona, and South American Drymaeus. 1897-1898’

(public domain)

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edited: 01.06.2021

Heliaster solaris A. H. Clark

24-rayed Sunstar (Heliaster solaris)

The 24-rayed Sunstar was described in 1840 as Asterias multiradiata Gray, a name that was already used for another species and that thus was replaced in 1920.

The species was endemic to the Galápagos Island group, where it appears to have been strictly restricted to the waters around the Isla Espanola.

The 24-rayed Sunstar disappeared during the El Niño southern oscillation event which affected the Galápagos Islands in 1982/83.

***

It appears very remarkable, at least to me, that all these extinctions of sealife from the Galápagos Islands in 1982/83 remained almost unnoticed til today.

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References:

[1] Graham J. Edgar; Stuart A. Banks; Margarita Brandt; Rodrigo H. Bustamantes; Angel Chiriboga; Lauren E. Garske; Peter W. Glynn; Jack S. Grove; Scott Henderson; Cleve P. Hickman; Kathy A. Miller; Fernando Rivera; Gerald M. Wellington: El Niño, grazers and fisheries interact to greatly elevate extinction risk for Galapagos marine species. Global Change Biology 16: 2876-2890. 2010

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edited: 29.11.2018

Naesiotus duncanus Dall

Duncan Island Snail (Naesiotus duncanus)

The Duncan Island Snail was described in 1893, it is restricted to the Isla Pinzón (aka. Duncan Island) in the Galapágos archipelago.

Except the largest specimens of B. nux, these shells are the largest Bulimuli described from the islands.” [1]

The shells reach sizes of about 1,8 cm in height and about 1,1 cm in diameter. [1]

***

The species was never observed alive and is known exclusively from empty shells, thus it certainly was already extinct before it was scientifically described; it probably fell victim to a severe drought. [2]

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References:

[1] George W. Tryon; Henry A. Pilsbry; a.o.: Manual of Conchology. Second series: Pulmonata. Vol 11: American Bulimulidae: Bulimulus, Neopetraeus, Oxychona, and South American Drymaeus. 1897-1898’    
[2] Guy Coppois; Sue Wells: Threatened Galápagos snails. Oryx 21(4): 236-241. 1987

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Depiction from: ‘George W. Tryon; Henry A. Pilsbry; a.o.: Manual of Conchology. Second series: Pulmonata. Vol 11: American Bulimulidae: Bulimulus, Neopetraeus, Oxychona, and South American Drymaeus. 1897-1898’  

(public domain)

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edited: 31.05.2021

Desmarestia tropica W. R. Taylor

Tropical Acidweed (Desmarestia tropica)

The Tropical Acidweed was endemic to the Galápagos archipelago, where, however, it was only ever found at two localities off Isla Floreana and off Isla Isabela, it was discovered in 1935 and described in 1945.

The species disappeared together with everal other marine algae species after a devastating El Niño event in 1982/83 and is now considered most likely extinct.

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References:

[1] Graham J. Edgar; Stuart A. Banks; Margarita Brandt; Rodrigo H. Bustamantes; Angel Chiriboga; Lauren E. Garske; Peter W. Glynn; Jack S. Grove; Scott Henderson; Cleve P. Hickman; Kathy A. Miller; Fernando Rivera; Gerald M. Wellington: El Niño, grazers and fisheries interact to greatly elevate extinction risk for Galapagos marine species. Global Change Biology 16: 2876-2890. 2010

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edited: 29.11.2018

Bifurcaria galapagensis (Piccone & Grunow) Womersley

Galapagos Sargasso Grass (Bifurcaria galapagensis)

This alga species was once one of the most common species growing in the lower intertidal and shallow subtidal habitats on the Galápagos Islands, but disappeared after a devastating El Niño event in 1982/83.

The species is now considered extinct. [1]

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References:

[1] Graham J. Edgar; Stuart A. Banks; Margarita Brandt; Rodrigo H. Bustamantes; Angel Chiriboga; Lauren E. Garske; Peter W. Glynn; Jack S. Grove; Scott Henderson; Cleve P. Hickman; Kathy A. Miller; Fernando Rivera; Gerald M. Wellington: El Niño, grazers and fisheries interact to greatly elevate extinction risk for Galapagos marine species. Global Change Biology 16: 2876-2890. 2010

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edited: 29.11.2018

Nesoryzomys darwini Osgood

Darwin’s Galapagos Mouse (Nesoryzomys darwini)  

Darwin’s Galapagos Mouse was described in 1929; it was endemic to the Isla Santa Cruz in the Galápagos archipelago.

It reached lengths of about 22 cm, including the tail; it was predominantly cinnamon rufous colored, the upper parts with a mixture of blackish hairs, the tail was dusky above and whitish below. [1]

Darwin’s Galapagos Mouse was last seen in 1930; the species disappeared shortly after, perhaps due to the introduction of Norway Rats (Rattus norvegicus (Berkenhout)), Black Rats (Rattus rattus (L.)), and feral cats.

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References:  

[1] Wilfred H. Osgood: A new rodent from the Galapagos Islands. Field Museum of Natural History 17(2): 21-24. 1929

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edited: 01.06.2021

Spatoglossum schmittii W. R. Taylor

Schmitt’s Brown Alga (Spatoglossum schmittii)

Schmitt’s Brown Alga was endemic to the waters surrounding the Galápagos Islands, where in former times it was quite common.

The species disappeared following a devastating El Niño in 1982/83 and is now considered most likely extinct.

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References:

[1] Graham J. Edgar; Stuart A. Banks; Margarita Brandt; Rodrigo H. Bustamantes; Angel Chiriboga; Lauren E. Garske; Peter W. Glynn; Jack S. Grove; Scott Henderson; Cleve P. Hickman; Kathy A. Miller; Fernando Rivera; Gerald M. Wellington: El Niño, grazers and fisheries interact to greatly elevate extinction risk for Galapagos marine species. Global Change Biology 16: 2876-2890. 2010

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edited: 29.11.2018

Nesoryzomys indefessus (Thomas)

Santa Cruz Rice Rat (Nesoryzomys indefessus)  

The Santa Cruz Rice Rat was described in 1899, it was restricted to the Isla Santa Cruz, Galápagos Islands.

The species disappeared soon after its description due to the introduction of Black Rats (Rattus rattus (L.)) and feral cats.

***

The Fernandina Rice Rat (Nesorhyzomys narboroughi Heller), one of only four Galápagos Islands rice rat species surviving until today, was formerly treated as a subspecies of the Santa Cruz Rice Rat.

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edited: 11.06.2020

Aegialomys galapagoensis ssp. galapagoensis (Waterhouse)

Galapagos Rice Rat (Aegialomys galapagoensis ssp. galapagoensis)  

In 1835, when Darwin visited the Galapagos Islands, he found a native mouse inhabiting Chatham Island [Isla San Cristóbal] and supposed it to be the only indigenous mammal of the islands. This species was described as Mus galapagoensis by Waterhouse … who adds Darwin’s notation as follows: “This mouse or rat is abundant in Chatham Island. I could not find it on any other island of the group.” From this it is evident that Darwin made an effort to obtain further rodents, but his narrative seems to indicate that he did not spend any time on Narborough and Indefatigable islands, the principal ones from which specimens have been taken subsequently.” [1]

The Galapagos Rice Rat is one of several virtually unknown endemic rodent species that inhabit, or inhabited, the Galápagos Islands.

This species, which might include two subspecies, is known from at least two, maybe three, of the islands, with Isla San Cristóbal having been inhabited by the nominate, which was endemic to that island.

This form was apparently last collected in 1855 by Charles Darwin himself during the second voyage of HMS Beagle, it must have gone extinct only some decades later and all subsequent findings were of subfossil remains only. 

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References:  

[1] Wilfred H. Osgood: A new rodent from the Galapagos Islands. Field Museum of Natural History 17(2): 21-24. 1929

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Depiction from: ‘John Gould: The Zoology of the Voyage of H.M.S. Beagle, under the command of Captain Fitzroy, during the years 1832-1836. Part III, Birds. London, Smith, Elder & Co. 1838’ 

(public domain)

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edited: 01.06.2021

Megaoryzomys sp. ‘Isla Isabela’

Isabela Giant Rice Rat (Megaoryzomys sp.)  

This is an up to date undescribed and thus unnamed species that is known exclusively from subfossil remains that had been found on Isla Isabele, Galápagos Islands. [1]

***

The Isabela sp. is apparently sometimes considered conspecific with the Galapagos Giant Rice Rat (Megaoryzomys curioi (Niethammer)) from the Isla Santa Cruz, another extinct rice rat species known only from subfossil remains.

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References:  

[1] Gustavo Jiménez-Uzcátegui; Bryan Milstead; Cruz Márquez; Javier Zabala; Paola Buitrón; Alizon Llerena; Sandie Salazar; Birgit Fessl: Galapagos vertebrates: endangered status and conservation actions. Galapagos Report 2006-2007

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edited: 11.06.2020

Galaxaura barbata R. Chou

Bearded Galaxaura Alga (Galaxaura barbata)

The Bearded Galaxaura Alga, described in 1945, was endemic to the waters around the Galápagos archipelago, where, however, it apparently was restricted to three localities only.

The species disappeared together with many other marine algae species after the devastating El Niño from 1982/83.

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References:

[1] Graham J. Edgar; Stuart A. Banks; Margarita Brandt; Rodrigo H. Bustamantes; Angel Chiriboga; Lauren E. Garske; Peter W. Glynn; Jack S. Grove; Scott Henderson; Cleve P. Hickman; Kathy A. Miller; Fernando Rivera; Gerald M. Wellington: El Niño, grazers and fisheries interact to greatly elevate extinction risk for Galapagos marine species. Global Change Biology 16: 2876-2890. 2010

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edited: 29.11.2018

Gracilaria skottsbergii W. R. Taylor

Skottsberg’s Alga (Gracilaria skottsbergii)

This marine algae species was endemic to the ocean surrounding the Galápagos Islands.

The species disappeared in 1982/83 due to the effects of a devastating El Niño event and is now considered extinct.

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References:

[1] Graham J. Edgar; Stuart A. Banks; Margarita Brandt; Rodrigo H. Bustamantes; Angel Chiriboga; Lauren E. Garske; Peter W. Glynn; Jack S. Grove; Scott Henderson; Cleve P. Hickman; Kathy A. Miller; Fernando Rivera; Gerald M. Wellington: El Niño, grazers and fisheries interact to greatly elevate extinction risk for Galapagos marine species. Global Change Biology 16: 2876-2890. 2010

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edited: 29.11.2018

Naesiotus lycodus (Dall)

Indefatigable Island Snail (Naesiotus lycodus)

The Indefatigable Island Snail was described in 1917, it is, or maybe was, endemic to Isla Santa Crus in the Galápagos Islands.

The species was found on tree trunks at 135 to 165 m elevation. [1]

The Indefatigable Island Snail was apparently not found during the most recent field searches and might be extinct.

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References: 

[1] William Healey Dall; Washington Henry Ochsner: Landshells of the Galapagos Islands. Proceedings of the California Academy of Sciences. Ser. 4. Vol. 17.: 141-185. 1928  

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Photo from: ‘’Abraham S. H. Breure: Annotated type catalogue of the Orthalicoidea (Mollusca, Gastropoda) in the Royal Belgian Institute of Sciences, Brussels, with descriptions of two new species. ZooKeys 101: 1-50. 2011

(under creative commons license (3.0))
https://creativecommons.org/licenses/by/3.0/

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edited: 01.06.2021

Dictyota galapagensis (Farlow) De Clerck

Galapagos Seaweed (Dictyota galapagensis)

This marine algae species was endemic to the ocean surrounding the Galápagos Islands.

The species disappeared after a decastating El Niño event in 1982/83 and is now considered extinct.

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References:

[1] Graham J. Edgar; Stuart A. Banks; Margarita Brandt; Rodrigo H. Bustamantes; Angel Chiriboga; Lauren E. Garske; Peter W. Glynn; Jack S. Grove; Scott Henderson; Cleve P. Hickman; Kathy A. Miller; Fernando Rivera; Gerald M. Wellington: El Niño, grazers and fisheries interact to greatly elevate extinction risk for Galapagos marine species. Global Change Biology 16: 2876-2890. 2010

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edited: 29.11.2018

Naesiotus sp. ‘nilsodhneri’

Nils Odhner’s Galapagos Snail (Naesiotus sp. ‘nilsodhneri’)

Nils Odhner’s Galapagos Snail was described in 1985, its species epithet, however, is now considered a nomen nudum. 

The species was restricted to the arid zones in the south-east of Isla Santa Cruz in the Galápagos archipelago; it was not found alive during the last recent field surveys and is now feared to be extinct. 

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References: 

[1] Guy Coppois: Etude de la spéciation chez les Bulimulidae endémiques de l’archipel des Galápagos (Mollusques, Gastéropodes, Pulmonés). Thèse de Doctorat, Libre de Bruxelles 1-283. 1985

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edited: 01.06.2021

Chelonoidis sp. ‘Santa Fé’

Santa Fe Tortoise (Chelonoidis sp.)  

The Isla Santa Fé, also known as Barrington Island, is a small, only about 24 km² large island, but may very well have once harbored its own endemic population of tortoises.  

There are three reasons to assume the former existence of a local population.:  

Firstly: Contemporaneous accounts by settlers and whalers, the latest of which dating from 1890, which also mention tortoise hunts on the island.  

Secondly: Subfossil and recent tortoise bones are well known from the island, yet no part of a carapace is known, thus the exact status of these remains cannot be ascertained.  

However, tortoises were transported in the 19th century from one island to another, without any kind of registering, thus these two abovementioned reasons may in fact also apply to a imported tortoise population.  But there is still the third and best reason ….  

Thirdly: By far the best evidence for the former existence of a endemic tortoise population comes from the island’s flora – the Barrington Island Tree Opuntia (Opuntia echios var. barringtonensis E. Y. Dawson) is an endemic variety of the typical tree-like opuntias that have evolved only on islands with tortoises, while the opuntia forms on tortoise-free islands are always growing as low creeping bushes, because, in the absence of large herbivorous tortoises they just did not need to develop a trunk.  

Thus there simply must have been a local race or species of tortoise on the Isla Santa Fé!  

***

In spite of everything, the Santa Fe Tortoise is still officially regarded as a hypothetical form.  

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References:  [1] Dennis M. Hansen; C. Josh Donlan; Christine J. Griffiths; Karl J. Campbell: Ecological history and latent conservation potential: large and giant tortoises as a model for taxon substitutions. Ecography Vol. 33(2) 272–284. 2010

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edited: 26.07.2013

Naesiotus trogonius (Dall)

Volcano Galapagos Snail (Naesiotus trogonius)

This species was described in 1917, it is endemic to Isla Isabela in the Galápagos archipelago, where it is thought to have inhabited the forests on the slopes of the volcano Ecuador.

The species was not found alive since the 1800s and is definitely extinct.

***

syn. Bulimulus trogonius Dall

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References: 

[1] William Healey Dall; Washington Henry Ochsner: Landshells of the Galapagos Islands. Proceedings of the California Academy of Sciences. Ser. 4. Vol. 17.: 141-185. 1928  

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edited: 01.06.2021

Naesiotus sp. ‘vanmoli’

Van Mol’s Galapagos Snail (Naesiotus sp. ‘vanmoli’)

Van Mol’s Galapagos Snail was described in 1985, its species name is now considered a nomen nudum, however.

The species was endemic to the southwestern part of the island of Santa Cruz in the Galápagos archipelago, where it was found in a narrow area only some 600 m wide in the arid zone at an altitude of about 65 m above sea level. [1]

Van Mol’s Galapagos Snail has not been found during the last field searches; it is thus believed to be most likely extinct. 

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References: 

[1] Guy Coppois: Etude de la spéciation chez les Bulimulidae endémiques de l’archipel des Galápagos (Mollusques, Gastéropodes, Pulmonés). Thèse de Doctorat, Libre de Bruxelles 1-283. 1985

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edited: 01.06.2021

Naesiotus sp. ‘josevillani’

Jose Villan’s Galapagos Snail (Naesiotus sp. ‘josevillani’)

Jose Villan’s Galapagos Snail was described in 1985, its species epithet, however, is now considered a nomen nudum, the reasons therefore are not known to me.

The species was endemic to the Isla Santa Cruz in the Galápagos archipelago, where it was found in the Scalesia forests of the higher altitudes. [1]

Jose Villan’s Galapagos Snail hasn’t been found during the most recent field searches and is thus considered very likely extinct.

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References: 

[1] Guy Coppois: Etude de la spéciation chez les Bulimulidae endémiques de l’archipel des Galápagos (Mollusques, Gastéropodes, Pulmonés). Thèse de Doctorat, Libre de Bruxelles 1-283. 1985

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edited: 01.06.2021

Naesiotus sp. ‘deridderi’

De Ridder’s Galapagos Snail (Naesiotus sp. ‘deridderi’)

This species was described in 1985, its species epithet, however, is a nomen nudum.

De Ridder’s Galapagos Snail occurred in the moister regions of the island of Santa Cruz; the animals apparently had a certain preference for the Arrow-leaved Sida (Sida rhombifolia L.) or the Prickly Sida (Sida spinosa L.), on whose branches they were often found. [1]

The species was not found alive during the last recent field studies and is feared to be extinct.

***

One of the few natural enemies of this species was the Woodpecker Finch (Camarhynchus pallidus (Sclater & Salvin)), which is known to occasionally pick up snails from the plants, which it subsequently beats against a twig or the like until the snail’s body detaches from the shell.  

The reason for the extinction of so many of the endemic snail species of the Galápagos Islands, however, is mainly due to the destruction of their habitats.  

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References:  

[1] Guy Coppois: Etude de la spéciation chez les Bulimulidae endémiques de l’archipel des Galápagos (Mollusques, Gastéropodes, Pulmonés). Thèse de Doctorat, Libre de Bruxelles 1-283. 1985
[2] G. Coppois: Threatened Galapagos bulimulid land snails: an update. In: E. Alison Kay: The Conservation Biology of Molluscs. Occasional Paper of the IUCN Species Survival Commision 9: 8-11. 1995 [3] C. E. Parent; R. P. Smith: Galápagos bulimulids: status report on a devastated fauna. Tentacle 14. 2006 
[4] C. E. Parent; B. J. Crepsi: Sequential colonization and diversification of Galapágos endemic land snail genus Bulimulus (Gastropoda, Stylommatophora). Evolution 60(11): 2311-2328. 2006

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edited: 01.06.2021

Blutaparon rigidum (B. L. Rob. & Greenm.) Mears

Santiago Amarant (Blutaparon rigidum)  

This species is known only from two collections that were made in 1905 and 1906 on the Isla Santiago in the Galápagos Islands.

The Santiago Amaranth was very well adapted to the dry habitats of its home island, it was a small profusely and compactly branched shrub and had small, needle-like leaves. [1]

The species disappeared due to the appetite of introduced donkeys, pigs and especially goats, whose numbers on Isla Santiago alone were estimated in 1980 as being as high as 80000 to 100000! [2]

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References:  

[1] I. Loren Wiggins; D. M. Porter; E. F. Anderson: Flora of the Galápagos Islands. Stanford University Press 1971 
[2] F. Cruz; V. Carrion; K. J. Campbell; C. Lavoie; C. J. Donlan: Bio-Economics of Large-Scale Eradication of Feral Goats from Santiago Island, Galápagos. The Journal of Wildlife Management 72(2): 191-200. 2009

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edited: 11.06.2020

Chelonoidis abingdonii (Günther)

Pinta Island Tortoise (Chelonoidis abingdonii)  

This species was described in 1877, it was endemic to the somewhat isolated Isla Pinta aka. Abingdon Island in the northern part of the Galápagos archipelago.

The species was thought to be extinct, when in 1971, a last individual was located, it was a male that was named ‘Lonesome George’ and was relocated to the Charles Darwin Research Station on Isla Santa Cruz for his safety.

Several attempts at mating Lonesome George with females of other tortoise species were unsuccessful, possibly because his species was not cross-fertile with the other species.

***

Lonesome George (see photo), the last member of its species, died at 24 June 2012.

***

It seems that there are still some individuals in existence that at least harbor some DNA of this extinct species within their blood.

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Photo: putneymark
https://creativecommons.org/licenses/by-sa/2.0/ 

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edited: 01.06.2021

Pyrocephalus dubius Gould

San Cristobal Flycatcher (Pyrocephalus dubius 

The Vermilion Flycatcher (Pyrocephalus rubinus (Boddaert)), probably the most colorful of the tyrant flycatchers, has several subspecies that are distributed over nearly all of South- and Central America. The two forms that occur on the Galápagos archipelago, however, are now treated as distinct species. [1]

***

The Little Vermilion Flycatcher, also known as Darwin’s Flycatcher (Pyrhocephalus nanus Gould) (see depiction below), is endemic to the Galápagos Islands, where it is widely distributed especially at the higher elevations, it does, however, not occur on Isla San Cristóbal, where the San Cristobal Flycatcher occurs, or rather did occur. 

The birds from Isla San Cristóbal differed from those of the other islands in their coloration. The males had a paler brown plumage, they had a paler red colored underside and a darker red crown. The females had a striking eye stripe, the underside was strong ocher to light rust colored, the throat was a little lighter ocher colored.

The San Cristobal Flycatcher apparently was last restricted to the very dry areas along the western coast of the island and were recorded as being extremely rare in the 1980s when large amounts of the native vegetation had been replaced by invasive plant species which again led to the disappearance of the native insect fauna which the birds fed upon.

The last record dates to 1987.

The San Cristobal Flycatcher was never seen since and is now considered most likely extinct. 

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References:  

[1] Ore Carmi; Christopher C. Witt; Alvaro Jaramillo; John P. Dumbacher: Phylogeography of the Vermilion Flycatcher species complex: Multiple speciation events, shifts in migratory behavior, and an apparent extinction of a Galápagos-endemic bird species. Molecular Phylogenetics and Evolution 102: 152-173. 2016  

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Darwin’s Flycatcher (Pyrhocephalus nanus)

Depiction from: ‘John Gould: The Zoology of the Voyage of H.M.S. Beagle, under the command of Captain Fitzroy, during the years 1832-1836. Part III, Birds. London, Smith, Elder & Co. 1838’  

(public domain) 

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edited: 11.06.2020

Naesiotus blombergi (Odhner)

Blomberg’s Galapagos Snail (Naesiotus blombergi)

Blomberg’s Galapagos Snail was described in 1950 (or 1951 according to other sources) based on 12 specimens that were collected 200 to 300 m above sea level on plants, bushes and trees on the Isla Santa Cruz in the Galápagos archipelago. [1]

The species was apparently last seen alive in 1974; it was not found during the most recent field surveys and is feared to be extinct. 

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References: 

[1] Steven M. Chambers; David W. Steadman: Holocene terrestrial gastropod faunas from Isla Santa Cruz and Isla Floreana, Galápagos: evidence for late Holocene declines. Transactions of the San Diego Society of Natural History 21(6): 89-110. 1986

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edited: 01.06.2021

Naesiotus adelphus Dall

Adelphus’ Galapagos Snail (Naesiotus adelphus)

Adelphus’ Galapagos Snail, described in 1917, is endemic to the Isla Santa Cruz, Galápagos Islands, where it inhabited the island’s arid zones. [1]  

***

Robert P. Smith, a gastropod specialist, investigated the snail populations on six of the larger islands of the Galápagos archipelago in 1970, including Isla Santa Cruz. By 2005 and 2005, when exactly the same areas were investigated again, many populations had disappeared.  

The touristic industry is booming on the islands, particularly on Isla Santa Cruz, and many of the former habitats are destroyed today, not only by development but also by the introduction of foreign species (animals and plants).  

The highlands, formerly home to endemic species like the Galapagos Miconia (Miconia robinsoniana Cogn.) and the Santa Cruz Scalesia (Scalesia pedunculata Hook. F.) are now overrun by introduced plant species, just like the lower regions of the island are.  

The snails are also killed by introduced ants, especially by the Little Fire Ant, also known as Electric Ant, (Wasmannia auropunctata (Roger)). [2][3]

***

Adelphus’ Galapagos Snail was not found in recent years, despite specific searches, and is considered most likely extinct.  

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References:  

[1] William Healey Dall; Washington Henry Ochsner: Landshells of the Galapagos Islands. Proceedings of the California Academy of Sciences. Ser. 4. Vol. 17.: 141-185. 1928 
[2] Christine E. Parent; Robert P. Smith: Galápagos bulimulids: status report on a devastated fauna. Tentacle 14. 2006
[3] Christine E. Parent; Bernard J. Crepsi: Sequential colonization and diversification of Galapágos endemic land snail genus Bulimulus (Gastropoda, Stylommatophora). Evolution 60(11): 2311-2328. 2006  

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Photo from: ‘William Healey Dall; Washington Henry Ochsner: Landshells of the Galapagos Islands. Proceedings of the California Academy of Sciences. Ser. 4. Vol. 17.: 141-185. 1928’

(under creative commons license (3.0))
https://creativecommons.org/licenses/by-nc-sa/3.0/

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edited: 01.06.2021

Sicyos villosus Hook. f.

Galapagos Bur Cucumber (Sicyos villosus)  

This species is only known from the type material, which was collected in the year 1853 by Charles Darwin on the island of Floreana. He wrote the following note on his herbaria sheet.:  

… in great beds injurious to vegetation ….”  

Therefore, the Galapagos Bur Cucumber obviously was quite common at that time.  

The reason for the complete extinction of this species lies, in all likelihood, in the feral goats, which until very recently could spread unfettered all over every place, on almost every single island in the Galápagos Archipelago.  

***

In the year 2006, a program for the eradication of feral goats (and donkeys) was started on the island of Floreana – the same program had proved very successful over several years on other islands of the archipelago. During this campaign the number of goats shot in the year 2008 alone was 1334.  

Unfortunately, goats are still illegally released on the Islands.  

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References:  

[1] Ira Loren Wiggins; Duncan M. Porter; Edward F. Anderson: Flora of the Galápagos Islands. Stanford University Press 1971 
[2] Alison Pearn: A Voyage Round the World: Charles Darwin and the Beagle Collections in the University of Cambridge. Cambridge University Press 2011

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edited: 11.06.2020

Phycodrina elegans (Setchell & N. L. Gardner) M. J. Wynne

Elegant Red Alga (Phycodrina elegans)

The elegant Red Alga was a marine algae species that was endemic to the ocean surrounding the Galápagos Islands, and it appears to have been very common in former times.

The species disappeared after or during a devastating El Niño event that took place between 1982 and 1983. However, the removal of lobsters and other fish predators from the environment by local fishers lead to a cascade of direct and indirect effects involving explosive population expansion of grazing (algae-feeding) sea urchins.

This again lead to the complete extinction of several endemic marine algae species from the waters around the Galápagos archipelago that happened almost unnoticed by the public.

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References:

[1] Graham J. Edgar; Stuart A. Banks; Margarita Brandt; Rodrigo H. Bustamantes; Angel Chiriboga; Lauren E. Garske; Peter W. Glynn; Jack S. Grove; Scott Henderson; Cleve P. Hickman; Kathy A. Miller; Fernando Rivera; Gerald M. Wellington: El Niño, grazers and fisheries interact to greatly elevate extinction risk for Galapagos marine species. Global Change Biology 16: 2876-2890. 2010

Photo: Macroalgal Herbarium

(under creative commons license (3.0))
http://creativecommons.org/licenses/by-nc/3.0

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edited: 29.11.2018