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New Species Discovered

Italy Ngala Offline
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Seven new species of Night Frogs (Anura, Nyctibatrachidae) from the Western Ghats Biodiversity Hotspot of India, with remarkably high diversity of diminutive forms
Nyctibatrachus athirappillyensis Garg, Suyesh, Sukesan & Biju, 2017
Nyctibatrachus manalari Garg, Suyesh, Sukesan & Biju, 2017
Nyctibatrachus pulivijayani Garg, Suyesh, Sukesan & Biju, 2017 
Nyctibatrachus radcliffei Garg, Suyesh, Sukesan & Biju, 2017
Nyctibatrachus robinmoorei Garg, Suyesh, Sukesan & Biju, 2017
Nyctibatrachus sabarimalai Garg, Suyesh, Sukesan & Biju, 2017 
Nyctibatrachus webilla Garg, Suyesh, Sukesan & Biju, 2017

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Figure 5: Holotype of Nyctibatrachus pulivijayani sp. nov. (ZSI/WGRC/V/A/902).
(A) Dorsolateral view, in life. (B) Size (SVL 13.3 mm) in comparison to the Indian five-rupee coin (24 mm diameter). © Dorsal view, in life. (D) Dorsal surface third finger disc, in preservation. (E) Dorsal surface of fourth toe disc, in preservation. (F) Ventral view, in life. (G) Femoral glands, in preservation. (H) Close-up of femoral glands after removal of skin showing multiple glands. (I) Lateral view of head, in preservation. (J) Ventral view of hand, in preservation. (K) Ventral view of foot, in preservation. (L) Schematic illustration of foot webbing.

Abstract:
"The Night Frog genus Nyctibatrachus (Family Nyctibatrachidae) represents an endemic anuran lineage of the Western Ghats Biodiversity Hotspot, India. Until now, it included 28 recognised species, of which more than half were described recently over the last five years. Our amphibian explorations have further revealed the presence of undescribed species of Nights Frogs in the southern Western Ghats. Based on integrated molecular, morphological and bioacoustic evidence, seven new species are formally described here as Nyctibatrachus athirappillyensis sp. nov., Nyctibatrachus manalari sp. nov., Nyctibatrachus pulivijayani sp. nov., Nyctibatrachus radcliffei sp. nov., Nyctibatrachus robinmoorei sp. nov., Nyctibatrachus sabarimalai sp. nov. and Nyctibatrachus webilla sp. nov., thereby bringing the total number of valid Nyctibatrachus species to 35 and increasing the former diversity estimates by a quarter. Detailed morphological descriptions, comparisons with other members of the genus, natural history notes, and genetic relationships inferred from phylogenetic analyses of a mitochondrial dataset are presented for all the new species. Additionally, characteristics of male advertisement calls are described for four new and three previously known species. Among the new species, six are currently known to be geographically restricted to low and mid elevation regions south of Palghat gap in the states of Kerala and Tamil Nadu, and one is probably endemic to high-elevation mountain streams slightly northward of the gap in Tamil Nadu. Interestingly, four new species are also among the smallest known Indian frogs. Hence, our discovery of several new species, particularly of easily overlooked miniaturized forms, reiterates that the known amphibian diversity of the Western Ghats of India still remains underestimated."
"Man still bears in his bodily frame the indelible stamp of his lowly origin." C. Darwin
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India Bronco Offline
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( This post was last modified: 03-08-2017, 12:19 PM by Bronco )

The BP oil spill led scientists to discover 60 new animal species living in the Gulf of Mexico

“So far we have identified over 60 species of fishes that have not been previously found in the Gulf, and of these at least seven are undescribed species,” Tracey Sutton, an oceanographer at Nova Southeastern University working on GoMRI, said in an email. An “undescribed species” is one that’s never been seen before, anywhere.

https://qz.com/923053/scientists-hired-by-bp-found-60-new-species-in-the-gulf-of-mexico-after-the-deepwater-horizon-oil-spill/
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Italy Ngala Offline
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( This post was last modified: 03-12-2017, 03:50 AM by Ngala )

Phylogenetic analysis of the Neotropical Pristimantis leptolophus species group (Anura: Craugastoridae): molecular approach and description of a new polymorphic species 
Pristimantis leptolophus Rivera-Correa, Jiménez-Rivillas & Daza, 2017

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From Mauricio Rivera-Correa, photo credits: Jose Fang

Abstract:
"Pristimantis, distributed throughout the New World tropics, is the most speciose vertebrate genus. Pristimantis presents an enormous morphological diversity and is currently divided into several demonstrably non-monophyletic phenetic species groups. With the purpose of increasing our understanding of Pristimantis systematics, we present the first phylogenetic analysis using molecular evidence to test the monophyly and infer evolutionary relationships within the Pristimantis leptolophus group, an endemic group of frogs from the highlands of the Colombian Andes. Our phylogenetic reconstruction recovers the group as monophyletic with high support, indicating general concordance between molecular data and morphological data. In addition, we describe a new polymorphic species lacking conspicuous tubercles, a regular attribute among species of the P. leptolophus species group and endemic from the Páramo de Sonsón complex (Antioquia, Colombia). The phylogenetic position of the new species is inferred and other systematic implications in the light of our results are discussed."
"Man still bears in his bodily frame the indelible stamp of his lowly origin." C. Darwin
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Sri Lanka Apollo Offline
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( This post was last modified: 03-23-2017, 05:53 PM by sanjay Edit Reason: Corrected the link )

New species of terrestrial crab found climbing on trees in Hong Kong



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Check the link

Edit: link is corrected
https://phys.org/news/2017-03-species-te...trees.html
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Netherlands peter Offline
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#20

Link doesn't work.
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Italy Ngala Offline
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#21

A new rupicolous species of gecko of the genus Hemidactylus Oken, 1817 from the Satpura Hills, Central India 
Hemidactylus chipkali Mirza & Raju, 2017

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Credits to David Raju.

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Abstract:
"We here describe a new species of rupicolous gecko from the Satpura Hills of central India. The new species is a member of the Hemidactylus brookii complex, and can be distinguished based on the following suite of characters: moderate sized species (SVL 54.3–74.2 mm); anterior postmental width equal to first infralabial; posterior postmental width equal to second infralabial, posterior postmental not in contact with first infralabial; enlarged, keeled, tubercles, fairly regularly arranged in 15–16 longitudinal rows on dorsum; two angular series of seven precloacal femoral pores separated by diastema of eight non-pored scales; non-pored scales equal to size of pored scales; scales bordering anterior edge of pored scales half the size of pored scales; five lamellae on digit I and seven on digit IV of manus as well as pes; lamellae on digit IV and V of pes absent on basal 25% of the digit; legs long and slender; ventral aspect of tail with broad caudal scales covering ~80% of tail; two subconical post cloacal spurs, anterior spur slightly larger than posterior spur."
"Man still bears in his bodily frame the indelible stamp of his lowly origin." C. Darwin
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United States tigerluver Offline
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#22

Rhinogobius mizunoi, A New Species of Freshwater Goby (Teleostei: Gobiidae) from Japan
Toshiyuki Suzuki 1), Koichi Shibukawa 2) & Masahiro Aizawa 3)

Abstract. A new freshwater goby, Rhinogobius mizunoi, is described based on six specimens from a freshwater stream in Shizuoka Prefecture, Japan. The species is distinguished from all congeneric species by the following combination of characters: I, 8 second dorsal-fin rays; 18–20 pectoral-fin rays; 13–18 predorsal scales; 33–35 longitudinal scales; 8 or 9 transverse scales; 10+16=26 vertebrae 26; first dorsal fin elongate in male, its distal tip reaching to base of fourth branched ray of second dorsal fin in males when adpressed; when alive or freshly-collected, cheek with several pale sky spots; caudal fin without distinct rows of dark dots; a pair of vertically arranged dark brown blotches at caudal-fin base in young and females.
 

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United States tigerluver Offline
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#23

Description of a New Blind and Rare Species of Xyliphius (Siluriformes: Aspredinidae) from the Amazon Basin Using High-Resolution Computed Tomography

Abstract:
Xyliphius sofiae, new species, is described based on a unique specimen exhibiting four autapomorphies: eyes absent vs. present (though reduced); color pale, lacking pigment vs. head and body darkly pigmented; branchiostegal rays five vs. four; and unculiferous tubercles on posterior body distributed evenly vs. enlarged unculiferous tubercles typically arranged in five distinct rows above pelvic-fin base to posterior end of caudal peduncle. In addition, the pectoral fin of X. sofiae, new species, has one ossified proximal radial vs. two in congeners (except X. magdalenae, not examined). Xyliphius sofiae, new species, differs from all congeners except X. lepturus by snout tip elongated and narrowly rounded vs. short and broadly rounded, often with small median notch; fifth ceratobranchial relatively narrow with elongate acicular teeth vs. broadly expanded, leaf-shaped, with shorter and broader, conical teeth; anterior limits of branchial apertures separated by distance less than length of aperture vs. greater than length of aperture; anal-fin rays modally nine vs. seven; and lateral line extending onto base of caudal-fin rays vs. finishing in hypural region. Based on the single specimen collected in the main channel of the Río Amazonas near Iquitos, Peru, we describe the osteology of X. sofiae, new species, using a non-invasive technique: high-resolution X-ray computed tomography (HRXCT). We consider Xyliphius lombarderoi Risso and Risso, 1964, a species based on a unique holotype that is now lost, to be a subjective junior synonym of X. barbatus Alonso de Arámburu and Arámburu, 1962. Variable characteristics are summarized for the seven species of Xyliphius treated here as valid, and their distributions are plotted based on a comprehensive review of museum specimens.


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United States tigerluver Offline
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#24

A new Papiliolebias killifish

Unfortunately the original paper is paywalled, but the above article is just as good.


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Italy Ngala Offline
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#25

A NEW SPECIES OF SEEDEATER (EMBERIZIDAE: SPOROPHILA) FROM THE IBERA GRASSLANDS, IN NORTHEAST ARGENTINA 
Sporophila iberaensis Di Giacomo, Lopez-Lanus & Kopuchian, 2017

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Abstract:
"We describe a new species of capuchino of the genus Sporophila (Emberizidae) of the Esteros del Ibera, province of Corrientes, in northeastern Argentina. This species would have remained unidentified due to lack of ornithological explorations in the central area of the Esteros del Ibera. It has been confused with immature individuals of other Sporophila species. We made observations of behavior and habitat, playback experiments, comparative analyzes of the vocalizations and plumage with other sympatric species of the same genus, and we found this species, which we have named Sporophila iberaensis, inhabiting wet grasslands from the edges of the marshes, having a unique vocal repertoire and a unique plumage. Because of its restricted geographical distribution and the threats that have their habitat, this new species should be categorized as Vulnerable on the IUCN Red List."

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Other articles related:
Archived 2016 topics: The newly described taxon Sporophila iberaensis is to be recognised as a species by BirdLife: request for information
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"Man still bears in his bodily frame the indelible stamp of his lowly origin." C. Darwin
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Italy Ngala Offline
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#26

A new species of Aphanotorulus (Siluriformes: Loricariidae) from the rio Aripuanã basin, Brazil
Aphanotorulus rubrocauda Oliveira, Py-Daniel & Zawadzki, 2017

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Fig. 1 Holotype of Aphanotorulus rubrocauda, INPA 33666, 150.5 mm SL, Brazil, Amazonas State, Apuí Municipality, Resex do Guariba, rio Aripuanã drainage, tributary of the rio Madeira basin, in lateral, dorsal, and ventral views. 

Abstract:
"The cis-Andean genus Aphanotorulus was recently revised and comprises six valid species: A. ammophilus, A. emarginatus, A. gomesi, A. horridus, A. phrixosoma and A. unicolor. Herein, a new species is described from tributaries of the rio Aripuanã basin, in Amazonas and Mato Grosso states, Brazil. The new species is easily distinguished from congeners by its color pattern: caudal fin with upper lobe mostly hyaline with dark spots along rays and membranes, and lower lobe red and without dark spots; and absence of dark spots in the lateral series of mid-ventral plates."
"Man still bears in his bodily frame the indelible stamp of his lowly origin." C. Darwin
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Italy Ngala Offline
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A new limestone-dwelling leaf-toed gecko (Gekkonidae: Dixonius) from Khao Sam Roi Yot massif, peninsular Thailand 
Dixonius kaweesaki Sumantha et al., 2017

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FIGURE 4. Live adult male Dixonius kaweesaki sp. nov.in situ (individual not collected). Photo. by M. Sumontha.

Abstract:
"We describe Dixonius kaweesaki sp. nov. from Khao Daeng, a limestone mountain in Khao Sam Roi Yot massif, Prachuap Khiri Khan Province, peninsular Thailand. It is diagnosed from all other species by a combination of maximal SVL of 41.6 mm; 12 or 13 longitudinal rows of dorsal tubercles; 24 longitudinal rows of ventrals across the abdomen; a continuous series of 9–11 precloacal pores in males, no pores in females; and two bold dark stripes from the snout to the base of the tail separated by a contrasting light vertebral stripe. It is the eighth species in the genus Dixonius. Lastly, we discuss the type locality of Phyllodactylus paviei, currently regarded as a junior subjective synonym of Dixonius siamensis."
"Man still bears in his bodily frame the indelible stamp of his lowly origin." C. Darwin
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Italy Ngala Offline
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Description of a new species of Cnemaspis (Squamata: Gekkonidae) from Knuckles Range of Sri Lanka
Cnemaspis kandambyi Batuwita & Udugampala, 2017

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Abstract:
"A new species of Cnemaspis Strauch is described from Knuckles Range of Sri Lanka. This new species had been previously confused with Cnemaspis podihuna Deraniyagala. Cnemaspis kandambyi sp. nov. closely resembles C. podihuna and C. molligodai Wickramasinghe & Munindradasa. Cnemaspis kandambyi sp. nov. differs from C. podihuna by having 7–8 (versus 3–6) unpored scales in each side of the precloacal-femoral pores row, lacking (versus having) an internasal scale, body (axilla to groin) relatively long 47.7–48.3 (versus 38.1–38.7)% of SVL and dorsum dark brown (versus bright yellow). Cnemaspis kandambyi sp. nov. also distinguished from C. molligodai by having 4 (versus 5) precloacal pores, 5–6 (versus 7–9) femoral pores on each side, precloacal pores not in an inverted V-shaped arrangement (versus in inverted V-shaped arrangement), lacking (versus having) a distinct black marking on nape and a black lateral stripe begins behind eye extends laterally beyond the origin of forearm (versus not extending beyond the origin of forearm). Additionally, Cnemaspis kandambyi sp. nov. and C. molligodai show discrete distribution: former restricted to Knuckles Range and the latter confined to Lowland wet zone of Sri Lanka. We confirm that, no type material of Cnemaspis podihuna survive in the current collection of the National Museum of Sri Lanka."

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"Man still bears in his bodily frame the indelible stamp of his lowly origin." C. Darwin
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Italy Ngala Offline
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A new karst dwelling species of the Gekko japonicus group (Squamata: Gekkonidae) from central Laos
Gekko nadenensis Luu, Nguyen, Le, Bonkowski & Ziegler, 2017

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FIGURE 2. A) Dorsolateral view of the holotype (VNUF R.2016.1); B) dorsolateral view of the male paratype (NUOLR.2016.2); C) lateral view of the female paratype VNUF R.2015.16) of Gekko nadenensis sp. nov. Photos V. Q. Luu. Coloration in life. Dorsal surface of head dark grey with grey blotches and brownish spots; posterior part of the orbit with a grey stripe; labials with grey and dark bars; crown region with a grey star aniseed shape; neck with three grey oval-shaped blotches; dorsal surface of body dark grey with grey blotches and brownish spots, largest blotches on the midbody; dorsal surface of fore and hind limbs brownish grey with light transverse bars; ventral surface of head, belly, and limbs cream with black dots; dorsal surface of tail with eight grey transverse bands, more distinct posteriorly; ventral tail grey-brown in forepart and with nearly closed bands in hindpart. Sexual dimorphism. Measurements and scalation of the female paratype are shown in Table 2. The female paratype has a larger size (SVL 77.1 mm versus 61.0–74.3 mm in males) and without precloacal pores. 

Abstract:
"A new species of the Gekko japonicus group is described from Khammouane Province, central Laos, based on morphological characters and molecular data. Morphologically, Gekko nadenensis sp. nov. is differentiated from the remaining congeners by a combination of the following characters: size moderate (SVL 61.0–77.1 mm); nares bordered with rostral; internasals absent; postmentals enlarged; interorbital scales between anterior corners of the eyes 28–30; dorsal tubercles absent; ventral scales between mental and cloacal slit 175–185; midbody scale rows 123–140; ventral scale rows 38–40; subdigital lamellae on first toes 13–15, on fourth toes 14–16; finger and toe webbing present at base; tubercles on dorsal surface of fore and hind limbs absent; precloacal pores six (3+3 or 5+1) in a discontinuous row in males, absent in the female; postcloacal tubercles 1 or 2; tubercles absent on dorsal surface of tail base; subcaudals distinctly enlarged; dorsal surface of body with greyish brown blotches. Molecular analyses demonstrated the new species is closely related to G. bonkowskii and G. thakhekensis, but separated from them by approximately 7% in genetic divergence as shown by a fragment of the mitochondrial ND2 gene."

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"Man still bears in his bodily frame the indelible stamp of his lowly origin." C. Darwin
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India Sanju Offline
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( This post was last modified: 02-15-2019, 12:30 PM by Sanju )

   
The new species, the Central African slender-snouted crocodile (Mecistops leptorhynchus), is the first to be fully described in more than 80 years.
Photograph by Matt Shirley
New crocodile species found hiding in plain sight

Studies of the Central African animal, which has unusually soft skin, also revealed its cousin to be critically endangered.
3 Minute Read By Douglas Main

PUBLISHED October 24, 2018
The Central African slender-snouted crocodile (Mecistops leptorhynchus) is one of two species of crocodiles in the genus Mecistops. It was once thought to be a population of the West African slender-snouted crocodile (Mecistops cataphractus) but was elevated to a species after two detailed studies, one in 2014 and the other in 2018.
It’s not every day that you find a new crocodile species. For the first time in more than 80 years, researchers have fully described and named a new species—the Central African slender-snouted crocodile—which is found in a broad swathe of the continent from Cameroon to Tanzania.
This species has been dubbed Mecistops leptorhynchus and characterized in a study published on October 24 in the journal Zootaxa.
The animal was, until now, considered to be the same species as its West African counterpart, Mecistops cataphractus, which will retain its original scientific name. The new designation brings the total population of the West African species down enough that it is now considered critically endangered. There are only about 500 individuals left in the wild, estimates Matt Shirley, study lead author and a researcher at Florida International University.
   
*This image is copyright of its original author
Skin of a specimen from
Gabon
Central African slender-snouted crocs have softer, smoother appearance than their West African cousins, which have larger, heavier scales and rougher skin, Shirley explains. The newly-described croc also lacks the bony crests on its skull found on its counterpart.
But the main differences lie in the genes—and these differences are significant. The paper shows the animals’ genetics first diverged more than eight million years ago, as volcanos arose in and around what is now Cameroon. This volcanic activity created impassable mountains that split the range of the reptiles in two, cutting off gene flow, and the two populations haven’t exchanged genes since, says Shirley, a National Geographic Explorer.
This isolation allowed the two species to diverge, and now the base pairs that make up certain important genes differ by more than five percent, he explains.
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Scientists have, of course, described other new species of crocodiles in recent years. For example, research by George Amato, at the American Museum of Natural History has shown that dwarf crocodiles are not one but three species. Shirley, Amato, and colleagues also discovered that there are actually two different species of Nile crocodiles.
But M. leptorhynchus is the first species since 1935 to go through the full formal descriptive and naming process, Shirley says. This involved sifting through scores of museum samples from around the world with assistance from colleagues at the University of Iowa and the University of Florida. Shirley himself also did intensive fieldwork in 14 African countries, and got malaria more than a dozen times in the course of the research, he says.
Their job was complicated by the fact that the “type” specimen, the original museum animal used to officially identify any given species, was nowhere to be found for M. cataphractus. That’s the Nazis’ fault: It was likely destroyed when German planes bombed London’s Natural History Museum in World War II, Shirley says. So the researchers had to designate a new one. What’s more, the type specimen for M. leptorhynchus is a juvenile, which muddled the effort since young crocs are more difficult to identify.

The study is “a continuing, repeated story about under-described diversity of African crocodiles,” says Amato, the director of conservation genomics at the Sackler Institute for Comparative Genomics, who wasn’t involved in this paper. The study should help spur conservation work for both types of crocodiles, but especially the West African species. Shirley and colleagues are collaborating with the governments of Côte d'Ivoire and Ghana as well as a number of NGOs to breed the animals in captivity and eventually release them to the wild. The largest such effort is taking place at a zoo in Côte d'Ivoire where more than 30 of the animals currently reside.
Habitat loss and poaching affect both species, although there are so few West African slender-snouted crocodiles left, they are almost impossible to find, says Shirley, who spent “months and years” of his life looking for them. In the end, he collected DNA samples from a mere 15 to 20.
The work is more urgent now than ever. “These are genuinely critically endangered,” Shirley says, “and [could] blink out at any moment.”

The species was described in 1835 on the basis of a specimen that had died at the London zoo and had been claimed to have been collected in the Fernando Po. Studies of specimens and their molecular sequences established that there were two different species which occurred in distinct hydrological zones. M. leptorhynchus is easily differentiated morphologically from M. cataphractus by the absence of a round tubercle or boss on the squamosal scale at the back of the head in the former and present in the latter. Gray (1844) listed Mecistops leptorhynchus as a synonym of M. bennettii even though the former has temporal priority. M. bennettii was subsumed as a junior synonym of M. leptorhynchus in Gray's Synopsis of the Species of Recent Crocodilians as he found that the type specimen of M. bennettii (NHMUK 1977.444) is actually an adult M. leptorhynchus. Article 67.9 of the International Code of Zoological Nomenclature (ICZN) states "If a validly fixed type species is later found to have been misidentified, the provisions of Article 70.3 apply." Article 70.3, in turn, states "If an author discovers that a type species was misidentified, the author may select, and thereby fix as type species, the species that will, in his or her judgment, best serve stability and universality, either." Additionally, the ICZN does not allow the specific epithet (species name) to be changed upon removal to a new genus unless that specific epithet already exists in the new genus. Since Mecistops was a new genus at the time of its description, M. bennettii is a nomen novum (replacement name). Shirley et al. (2018) found that the type specimen of M. bennettii is morphologically and geographically readily assignable to M. cataphractus so they synonymized M. bennettii with M. cataphractus.

https://www.nationalgeographic.com/anima...rica-news/
https://en.wikipedia.org/wiki/Central_Af..._crocodile

Introduction of the Dwarf crocodile:
The dwarf crocodile (Osteolaemus tetraspis), also known commonly as the African dwarf crocodile, broad-snouted crocodile, or bony crocodile, is an African crocodile that is also the smallest extant crocodile species. Recent sampling has identified three genetically distinct populations. Some feel that the findings should elevate the subspecies to full species status. Osteolaemus tetraspis is currently the only species included in the genus Osteolaemus, with two recognized subspecies:
  • O. t. tetraspis Cope, 1861
  • O. t. osborni (Schmidt, 1919) – Congo (or Osborn’s) dwarf crocodile
The second subspecies has had a somewhat convoluted taxonomical history. It was first described as Osteoblepharon osborni by Schmidt in 1919, based on a few specimens from the Upper Congo River Basin in what is now the Democratic Republic of Congo. However, Inger in a 1948 paper found the specimens wanting of characteristics that would justify a generic separation from Osteolaemus and referred the specimens to Osteolaemus osborni. In 1961, it was reduced to subspecies rank.

A study of morphology published in 2007, and studies of DNA in 2009, 2013 and 2015 indicate that three distinctly different populations of Osteolaemus may merit full species recognition. These are O. tetrapis (Central Africa, except the Congo River Basin), O. osborni (Congo River Basin), and a third possibly unnamed species (West Africa). The name afzelii Lilljeborg, 1867 (type locality: Sierra Leone) may be available for the West African species. Uncertainty exists for the population in Nigeria (between O. tetrapis and the possibly unnamed West African species) as it has not been studied. A fourth clade was found in a study of captives in 2013, but where members of this clade live in the wild is unclear. In some regions, the species may come into contact. For example, Cameroon is home to both O. tetrapis and O. osborni.

Dwarf crocodiles attain a medium adult length of 1.5 m (4.9 ft), though the maximum recorded length for this species is 1.9 m (6.2 ft). Adult specimens typically weigh between 18 and 32 kg (40 and 71 lb), with the largest females weighing up to 40 kg (88 lb) and the largest males weighing 80 kg (180 lb). This makes it the smallest living crocodile species, although the Cuvier's dwarf caiman (Paleosuchus palpebrosus), a member of the family Alligatoridae, is smaller at up to about 1.7 m (5.6 ft). If the Congo dwarf crocodile (O. osborni) is recognized as a valid species, it would be both the smallest crocodile and the smallest crocodilian since it does not surpass 1.2 m (3.9 ft). Adults are all dark above and on their sides, while the underside is yellowish with black patches. Individuals living in caves may have orange patches, apparently due to acidic bat guano that erodes the skin of the crocodile. Juveniles have a lighter brown banding on body and tails and yellow patterns on the head.

As a result of its small size and heightened vulnerability to predation, this species of crocodile has a heavily armoured neck, back, and tail and also has osteoderms on its belly and underside of the neck.

Osteolaemus has a blunt short snout, as long as it is wide, similar to that of a Cuvier's dwarf caiman, probably a result of occupying a similar ecological niche. The dentition consists of four premaxillary teeth, 12 to 13 on the maxilla, and 14 to 15 on the dentary bone.

O. t. tetraspis has lighter colours, a more pointed, upturned snout, and more body armour than O. t. osborni.

Dwarf crocodiles attain a medium adult length of 1.5 m (4.9 ft), though the maximum recorded length for this species is 1.9 m (6.2 ft). Adult specimens typically weigh between 18 and 32 kg (40 and 71 lb), with the largest females weighing up to 40 kg (88 lb) and the largest males weighing 80 kg (180 lb). This makes it the smallest living crocodile species, although the Cuvier's dwarf caiman (Paleosuchus palpebrosus), a member of the family Alligatoridae, is smaller at up to about 1.7 m (5.6 ft). If the Congo dwarf crocodile (O. osborni) is recognized as a valid species, it would be both the smallest crocodile and the smallest crocodilian since it does not surpass 1.2 m (3.9 ft). Adults are all dark above and on their sides, while the underside is yellowish with black patches. Individuals living in caves may have orange patches, apparently due to acidic bat guano that erodes the skin of the crocodile. Juveniles have a lighter brown banding on body and tails and yellow patterns on the head.

As a result of its small size and heightened vulnerability to predation, this species of crocodile has a heavily armoured neck, back, and tail and also has osteoderms on its belly and underside of the neck.

Osteolaemus has a blunt short snout, as long as it is wide, similar to that of a Cuvier's dwarf caiman, probably a result of occupying a similar ecological niche. The dentition consists of four premaxillary teeth, 12 to 13 on the maxilla, and 14 to 15 on the dentary bone. O. t. tetraspis has lighter colours, a more pointed, upturned snout, and more body armour than O. t. osborni.

Dwarf crocodiles range across tropical regions of Sub-Saharan West Africa and Central Africa. Such a distribution greatly overlaps with that of the slender-snouted crocodile, encompassing countries as far west as Senegal, reaching Uganda in the east, and ranging as southerly as Angola. The last confirmed record from Uganda was in the 1940s, but whether the species, which is easily overlooked, still survives there is unclear (it was always marginal in this country, only occurring in the far southwest).

Dwarf crocodiles live from lowlands to mid-altitude in streams, small rivers, swamps, pools and mangrove, but generally, avoid main sections of large rivers. Most of their range is within forested regions, but it may extend into more open regions where the streams or river are well-shaded. Unlike most crocodiles, dwarf crocodiles only rarely bask in the sun. During the night they may move some distance from water on land. Reports exist of dwarf crocodiles in isolated pools in the savannah. Dwarf crocodiles living long-term in caves are known from western Gabon,[18] which stand out as an isolated genetic group.

The dwarf crocodile is a timid and mainly nocturnal reptile that spends the day hidden in pools or burrows, although it occasionally may be active during the day. Foraging is mainly done in or near the water, although it is considered to be one of the most terrestrial species of crocodilian and may expand the feeding pattern to land in extensive forays, especially after rains.

Dwarf crocodiles are generalist predators and have been recorded feeding on a wide range of small animals such as fish, crabs, frogs, gastropods, insects, lizards, water birds, bats and shrews. In a study in the Democratic Republic of the Congo the primary food item was fish, and in a study in Nigeria, the primary food items were gastropods and crabs. In the Congo there is a level of seasonality in its diet, changing from fish in the wet season to crustaceans in the dry season where fish are less available. Plant material has also been found in the stomach of dwarf crocodiles, but it is suspected that this is ingested by accident. They can survive for relatively long periods without food. During the dry season, dwarf crocodiles often retreat to deep holes.

True to its solitary, nocturnal nature, a dwarf crocodile digs out a burrow in which to hide and rest during the day, which can sometimes have a submerged entrance. An individual lacking the right conditions to do so usually lives between tree roots that hang over the ponds where it lives.
https://en.wikipedia.org/wiki/Dwarf_crocodile

The Orange Cave-Dwelling and Digging Crocodiles
Scientists in Gabon discover orange, cave-dwelling crocodiles
Thursday 28 June 2018 - 1:20 pm

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This photograph taken on 11 August 2010, shows an orange cave crocodile captured in a cave in Abanda in the Ogooue-Maritime, in the south-west of Gabon.
LIBREVILLE - The West African state of Gabon is famous for its biodiversity but in a galaxy of spectacular finds, one stands out: orange crocodiles.

Scientists looking for traces of ancient human life stumbled upon the unusual reptiles decade ago as they searched in the gloom of isolated caves in Gabon&39;s southern Omboue region.
"When I approached with the torch in the cave, I saw red eyes... crocodiles!", said geo-archaeologist Richard Oslisly. It was only two years later when they hauled one out into the light that they realised it was orange.
"At first we thought the colour came from their food because we saw that these reptiles ate orange bats," said Oslisly.
The scientists discarded other theories before speculating that lack of light in the Abanda caves may have caused depigmentation and urea in bat droppings may then have induced an orange hue like this: https://youtu.be/Ru2gAI6qKGY

Under this theory, "the bat guano began to attack their skin and transformed their colour," said speleologist Olivier Testa, a member of the research team.
Dwarf crocodiles (Osteolaemus tetraspis) are a well-studied species, but the ones in the cave complex stand out in the way they have adapted to their habitat.

Oslisly, Testa and an American researcher, Matthew Shirley, have carried out multiple expeditions to study the unusual animals, which can grow to 1.7 metres.
"We think these... crocodiles have been in the Abanda caves for around 3,000 years, which correlates fairly well with a time when the sea level fell and this coastal zone became terrestrial once again," Shirley said.
Mapping the cave complex, the scientists found four orange specimens in a community of 40.
The crocodiles of "normal" colour, they discovered, live in grottos which are connected to the surface.
But the orange-coloured ones live in caverns that are accessible today only from vertical shafts.
However, the cave system also has smaller horizontal connections, which are filled with water or dry according to the level of the groundwater.
One possibility is that the orange crocodiles entered their present habitat through narrow openings which they then outgrew and could not return, and their skin eventually changed colour in response to the bat guano.
In the total darkness, the animals survive on a diet of bats and crickets, unlike above-ground crocodiles of the same species which feed on fish and crustaceans.
"It&39;s an especially challenging environment," Shirley said.
A comparison of cave-dwelling and above-ground crocodiles confirms that they have not become separate species.
However, the subterranean creatures -- whether orange or normal colour -- have developed a specific "genetic signature," apparently from adapting to life underground, and this is transmitted from generation to generation, said Shirley.
The crocodile is already a protected species in Gabon, known for its geological and biological diversity, but Oslisly wants the Abanda site to become a "wholly protected sanctuary".
"There&39;s much more to learn in the Abanda caves," he said, pledging to develop the site for "scientific tourism".
A Unique discovery
The Abanda caves in Gabon host a population of cave-dwelling crocodiles. They spent their entire life in these caves and had to adapt to the underground conditions. Who are these unique reptiles living in the caves of Gabon?
How did these crocodiles happen to be trapped in Abanda caves?

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*This image is copyright of its original author

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We don't have a definite answer to this question. The Abanda cave network is based on a system of faults. Some of the crocodiles live completely isolated from the exterior, the only access being through a 7 m deep shaft.

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*This image is copyright of its original author

We think that entrances existed in the past, but they are now filled with sediments, preventing the crocodiles to escape.
One question needs also to be solved, the reason why these crocodiles initially found shelter in these caves. This is in Africa's Gaban county. In them, some rainforest has a lot of water bodies. In them, are some weird caves, scientists on expedition have taken oxygen masks and luminescence torches in dark muddy caves with full of Bat shit, it was difficult to walk. The caves are filled with dense smoke and poisonous gases. After going deep, they saw some big eyes reflections, it was croc but it is orange in colour. As they go deeper, they found numerous crocs there. Finally, they found that these reptiles are going underground by digging tunnels, they formed a tunnel network under that cave. They formed their own habitat inside that cave environment. This was astonishing and first time discovered by these people. They took blood sample 30-40 crocodiles. When they examined their stomach content, they found strangely, some small cave-dwelling creatures, plant materials like algae and mosses. These incredibly rare crocodiles were about 200 in that cave. Nile crocs are known to aestivate in summer or dry season in underground caves dug by them beside river bed to escape drought in advance. But these are only crocodile species which made dark caves as their natural habitats. These were found to be evolving as separate species from dwarf crocodiles and hence, scientists are doing more research on these caves and crocs.
How many of them are there?
During our two expeditions in 2010 and 2011, organised by IRD and Foundation Liambissi, we observed twenty individuals in the caves. Almost all of them could be captured by Matthiew Shirley, who measured them, took samples, marked them and released them.
Are they different from the outside crocodiles?
They look very close to the Dwarf Crocodile, (Osteolaemus tetraspis), however, they differ by several points. They are broader, almost blind, and their skin is orange-coloured, which has never been observed in the dwarf crocodile from the exterior.
The biggest captured specimen was 1.70m long. This length is very high for the species and the crocodile must be very old. We observed several individuals more than one meter long.
Our hypothesis to explain their orange colour is a chemical attack of the skin. They live permanently in a eau croupie dans laquelle fermentent les excréments de chauves-souris. L'odeur est d'ailleurs presque insoutenable.

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And genetically?
The first DNA analysis made in 2010 showed a genetic difference of a few percents between the crocodile inside the caves and the crocodile found elsewhere in Gabon. The population has therefore been isolated for several thousand years. More blood samples have been taken in 2011, both on cave crocodiles and on outside crocodiles. The number of the sample will give statistically significant results.
In the caves, what are their food diet?
These crocodiles live in the absolute darkness. The food is scarce and poorly diversified. We obtained the stomach content by regurgitation and it appears that the cave crocodiles have a very original diet. Whereas outside crocodiles feed on shrimps, crabs, frogs, we found in cave crocodiles' stomachs crickets, bats, insects and a big amount of algae.

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What will be the next steps of your research?
We want to know why these crocodiles live in what seems to be an inhospitable environment. Is it to survive a past climate change ? to be protected from predators? Have they just been trapped there?
Many questions a new expedition will bring answers.
You can check here the first results of the 2015 Abanda expedition
http://www.abanda-expedition.org/orange-...e-012.html
https://www.enca.com/life/scientists-in-gabon-discover-orange-cave-dwelling-crocodiles









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