Wednesday, March 21, 2018

[Mollusca • 2018] Bohuslania matsmichaeli • First True Brackish-water Nudibranch Mollusc provides New Insights for Phylogeny and Biogeography and Reveals Paedomorphosis-driven Evolution

Bohuslania matsmichaeli 
Korshunova, Lundin, Malmberg, Picton & Martynov, 2018

A unique example of brackish water fjord-related diversification of a new nudibranch genus and species Bohuslania matsmichaeli gen. n., sp. n. is presented. There are only few previously known brackish-water opisthobranchs and B. matsmichaeli gen. n., sp. n. is the first ever described brackish-water nudibranch with such an extremely limited known geographical range and apparently strict adherence to salinity levels lower than 20 per mille. Up to date the new taxon has been found only in a very restricted area in the Idefjord, bordering Sweden and Norway, but not in any other apparently suitable localities along the Swedish and Norwegian coasts. We also show in this study for the first time the molecular phylogenetic sister relationship between the newly discovered genus Bohuslania and the genus Cuthona. This supports the validity of the family Cuthonidae, which was re-established recently. Furthermore, it contributes to the understanding of the evolutionary patterns and classification of the whole group Nudibranchia. Molecular and morphological data indicate that brackish water speciation was triggered by paedomorphic evolution among aeolidacean nudibranchs at least two times independently. Thus, the present discovery of this new nudibranch genus contributes to several biological fields, including integration of molecular and morphological data as well as phylogenetic and biogeographical patterns.


Fig 2. Morphology of Bohuslania matsmichaeli gen. n., sp. n.
A, Dorsal appearance of the holotype; B. Ventral appearance holotype; C. Living specimen and its egg mass in situ; D, Pharynx and jaws (Paratype GNM 9024); E, Masticatory processes of jaws with denticles 

Fig 2. Morphology of Bohuslania matsmichaeli gen. n., sp. n. F, Radula, central teeth (Holotype); G, Reproductive system of the holotype (non-destructive SEM with “nano-coating”); H, copulative organ (same technique as in G); I, Scheme of reproductive system.
Scales: 10 μm (F, G, H), 500 μm (I).
Abbreviations: a–ampulla, fgm–female gland mass, fgo–female opening, hd–hermaphroditic duct, p–penis, pg–penial gland, pr–prostate, ps–penial sheath, rsp–proximal receptaculum seminis, vd–vas deferens, v–vagina.

Fig 2. Morphology of Bohuslania matsmichaeli gen. n., sp. n. A, Dorsal appearance of the holotype; B. Ventral appearance holotype; C. Living specimen and its egg mass in situ; D, Pharynx and jaws (Paratype GNM 9024); E, Masticatory processes of jaws with denticles;
F, Radula, central teeth (Holotype); G, Reproductive system of the holotype (non-destructive SEM with “nano-coating”); H, copulative organ (same technique as in G); I, Scheme of reproductive system.
 Scales: 10 μm (F, G, H), 500 μm (I). Abbreviations: a–ampulla, fgm–female gland mass, fgo–female opening, hd–hermaphroditic duct, p–penis, pg–penial gland, pr–prostate, ps–penial sheath, rsp–proximal receptaculum seminis, vd–vas deferens, v–vagina.

Fig 1. Phylogenetic tree of aeolidacean nudibranchs based on concatenated molecular data (COI + 16S + 28S + H3) represented by Bayesian Inference (BI). The aeolidacean families are highlighted. The brackish-water living, but non-related taxa Bohuslania gen. n. and Tenellia are indicated as “BW”. Numbers above branches represent posterior probabilities from Bayesian Inference. Numbers below branches indicate bootstrap values for Maximum Likelihood.

Fig 4. Ontogenetic and phylogenetic framework for evidence of parallel paedomorphosis driven-evolution within the brackish-water nudibranchs of the families Cuthonidae (Bohuslania gen. n.) and Trinchesiidae (Tenellia adspersa). Adults (14 and 20 mm) of marine species Cuthona nana and C. divae respectively, considerably differ from adults of brackish-water Bohuslania matsmichaeli gen. n., sp. n., whereas juveniles of C. nana (6 mm length) and C. divae (5 mm length) are similar to the adult of B. matsmichaeli (10 mm length) by presence of only 3–4 anterior ceratal rows and absence of numerous pre-rhinophoral digestive gland branches. Because Bohuslania, compared to Cuthona, does not develop further to reach the stage with numerous anterior ceratal rows, this stage is considered missing in Bohuslania (indicated by “X” on the scheme) due to heterochronic developmental shifts leading to the adult paedomorphic external morphology. The brackish-water species Tenellia adspersa (adult, 6 mm length) demonstrates a striking paedomorphic feature in presence of secondary oral veil. However, it belongs to the family Trinchesiidae which is more distantly related to the family Cuthonidae according to the present molecular phylogenetic analysis (Figs 1 and 2). Since the appearance of the small oral veil occurs in earlier ontogeny of aeolidacean nudibranchs and predates formation of oral tentacles and numerous anterior ceratal rows, the two stages of development of external features are considered as missing in Tenellia adspersa (indicated by two “X” on the scheme).


The molecular phylogenetic results confirm the morphological analysis data. From the only other genus of the family Cuthonidae, Cuthona Alder & Hancock, 1855, Bohuslania gen. n. is morphologically readily distinguished by absence of the pre-rhinophoral rows of cerata and considerably smaller number of rows of the anterior digestive gland.

Class Gastropoda
Order Nudibranchia
Family Cuthonidae Odhner, 1934

Diagnosis: Body wide. Notal edges fully reduced. Cerata non-elevated, numerous per row. Ceratal rows branched. Anus acleioproctic or cleioproctic. Radula formula 0.1.0. Central teeth with strong cusp not compressed by adjacent lateral denticles. Vas deferens short, with weak prostate. Supplementary gland present, inserts to unarmed copulative organ.

Included genera: Cuthona Alder & Hancock, 1855, Bohuslania gen. n.

Genus Bohuslania gen. n.
Type species: Bohuslania matsmichaeli gen. n., sp. n.

Diagnosis: Three to four anterior rows of cerata, pre-rhinophoral cerata absent, head broad, oral tentacles placed towards lateral edges of head, no anterior foot corners, anus acleioproctic, jaws with single row of simple denticles, radular teeth narrow with prominent cusp, penis without stylet.

Etymology: After Bohuslän region in southern Sweden, where the only locality of this new genus and species in the Idefjord is known.

Species included: B. matsmichaeli sp. n.

Bohuslania matsmichaeli sp. n.

Holotype: Sweden, Idefjord, 59° 02.400' N 11° 24.430'E, inner part of the Idefjord, off beach east of Boråsgården, 7 m depth, 2013-10-8, coll. Mats Larsson and Michael Lundin (ZMMU Op-600, 3 mm in length preserved, 10 mm living length).

Type locality: Idefjord, Bohuslän region.

Etymology: This species is named in honour of Mats Larsson and Michael Lundin, who were the first to discover this unique taxon.

Description: The length of the preserved holotype is 3 mm (living is 10 mm). The preserved length of 9 mature paratype specimens ranged from 3 to 4 mm. The body is moderately broad (Fig 2A and 2B). The rhinophores are slightly longer than oral tentacles, smooth. The cerata are relatively long, thin and finger-shaped. Pre-rhinophoral cerata absent. Ceratal formula of the holotype: right (4,5,5; Anus,4,3,3,2,2) left (3,4,5; 4,3,2,2). Paratype specimens possess 3–4 pre-anal branches of anterior digestive gland. The head is broad, semicircular, oral tentacles placed towards edges of the head. The foot is moderate, anteriorly rounded, no foot corners.

Biology: Inhabits mixed environment with stones and mud in shallow (5–7 m) brackish water (15–18 per mille). The athecate hydroid Cordylophora caspia was found in the area and can be a probable food source for B. matsmichaeli. Potentially two techate hydroids could possibly also inhabit the area, Gonothyraea loveni and Laomedea flexuosa but these were not found together with B. matsmichaeli. The egg mass is in the shape of a narrow whitish spiral cord with about 3 whorls (Fig 2C). The egg mass contains about 250 eggs.

Distribution: To date known only from the internal parts of the Idefjord in the Bohuslän region.

Tatiana Korshunova, Kennet Lundin, Klas Malmberg, Bernard Picton and Alexander Martynov. 2018. First True Brackish-water Nudibranch Mollusc provides New Insights for Phylogeny and Biogeography and Reveals Paedomorphosis-driven Evolution.  PLoS ONE. 13(3): e0192177.  DOI:   10.1371/journal.pone.0192177


[Herpetology • 2018] Tropidurus azurduyae • A New Collared Lizard (Tropidurus, Tropiduridae) endemic to the western Bolivian Andes and Its Implications for Seasonally Dry Tropical Forests

Tropidurus azurduyae
Carvalho, Rivas, Céspedes & Rodrigues, 2018

In this study we describe Tropidurus azurduyae, a new species of lizard endemic to the Andes. This species is restricted to inter-Andean dry valleys of central and southern Bolivia, within the ecoregion known as Bolivian Montane Dry Forests. It is currently known from the departments of Chuquisaca, Cochabamba, Potosí, and Santa Cruz, where it ranges in elevation from about 1000 to 2800 m. In addition, our analyses of closely related populations of Tropidurus from Argentina, Bolivia, Brazil, and Paraguay revealed undescribed species in central and northeastern Brazil and eastern Bolivia that render T. etheridgei Cei, 1982, paraphyletic. These results underscore the need for a comprehensive revision of peripheral and disjunct populations currently assigned to widely distributed species of Tropidurus. The phylogenetic relationships and distribution patterns of these new taxa concur with recent findings supporting seasonally dry tropical forests and open formations of dry vegetation from South America as distinct biotic units. Furthermore, they offer no support for seasonally dry tropical forests as closely related areas. In line with these discoveries, we refute biogeographic scenarios based exclusively on vicariance to explain the biogeographic history of Tropidurus

Adult male of Tropidurus azurduyae, sighted (not collected) at the type locality in the Torotoro National Park, Potosí, Bolivia.

FIGURE 1. Habitats visited in the Torotoro National Park, Potosí, Bolivia.
A–D, Prepuna (~2798 m). E–G, Inter-Andean dry valleys at the type locality of Tropidurus azurduyae (~2264 m). H, Adult male of Tropidurus azurduyae, sighted (not collected) at the type locality of the species.

FIGURE 3. Live specimens of Tropidurus azurduyae.
E, G, Adult female (allotype MHNC-R 3009); F, H, Adult male (holotype MHNC-R 3011). 

Tropiduridae Bell, 1843
Tropidurus Wied, 1825
Tropidurus azurduyae, n. sp.

Morphological Diagnosis: Tropidurus azurduyae is here morphologically diagnosed as a Tropidurus based on the observation of a set of characters suggested by Frost et al. (2001) as exclusive to the genus: skull not highly elevated at the level of the orbits; “flash” marks on underside of thighs present; circumorbitals distinct from other small supraorbital scales; lateral fringe not developed on both sides of fourth toes; enlarged middorsal scale row absent; tail terete; and hemipenis attenuate without apical disks. The presence of a maxilla not broad, nutritive foramina of maxilla strikingly enlarged, lingual process of dentary extending over lingual dentary process of coronoid, angular strongly reduced, and absence of medial centrale could not be examined without dissecting or clearing and staining specimens. These characters should be revised whenever larger series of individuals become available. 
Tropidurus azurduyae is a member of the T. torquatus group per Frost et al. (2001). It differs from other species groups by lacking an enlarged middorsal scale row (well marked in species of the T. spinulosus group, especially in males), by exhibiting black “flash” marks on the underside of thighs and cloacal flap of adult males (yellow, cream, or orangey “flash” marks are present in males of the T. spinulosus group), and also by lacking a dorsoventrally flattened body (as observed in species of the T. semitaeniatus group and, more moderately, in T. bogerti). 
Tropidurus azurduyae is the only species in the genus with lower flanks pigmented orange, a condition consistently observed in both sexes (fig. 3E–H). Its ventral head is darkly pigmented and offers contrast to the light circular blotches present on chin and also laterally (fig. 3G, H). The ground color of its throat is charcoal gray impregnated with strong orange coloration (fig. 3G, H). A pair of mite pockets is present on the lateral neck, with the posterior one larger; the anterior pocket originates lower than the posterior, but both usually end ventrally at the same level (fig. 3F). No pockets are found in the armpit and inguinal region of the new species. An elliptical or subrhomboidal black mark is present on the mid venter of adult males of T. azurduyae in addition to black “flash” marks on the underside of thighs and precloacal flap (fig. 3H). Tropidurus azurduyae is saxicolous, but may climb tree trunks and fallen logs occasionally (fig. 1H). In combination, this set of characters provides a safe diagnosis, distinguishing T. azurduyae from all other congeners.

Etymology: The species name azurduyae is a noun in the feminine genitive case honoring Juana Azurduy de Padilla (Chuquisaca, Bolivia: July 12, 1780–May 25, 1862), one of the most distinguished Latin American leaders who bravely fought for the independence of the Spanish territory of Upper Peru, which comprised part of today’s Bolivia and Peru, and formed along with Argentina, Uruguay, and Paraguay the Viceroyalty of the Río de La Plata during colonial times. Her memory remained nearly forgotten for more than a century, until President Cristina Kirchner conferred on her the title of General of the Argentinian Army in 2009, and in that same year, the Bolivian Senate promoted Juana Azurduy posthumously to the rank of Marshal of the Republic, declaring her “Liberator of Bolivia.” Although the biography of Juana Azurduy assuredly places her as one of the most important women of Latin America, the history of her fight for freedom and equality has not received enough attention outside history classes and political events. Naming Tropidurus azurduyae we do not aim to merely reverence her as a historical personage and revolutionary soldier, but to genuinely honor her intelligence, courage, and heroic actions against a male-dominated colonialist world whose roots remain alive at the present time. This is an affirmative action to remind all Latin American women and men of our female heritage of strength and combativeness. 

 For a more comprehensive biography of Juana Azurduy, refer to the work of the Argentinian writer Mario “Pacho” O’Donnnel (1994), available online ( Those interested may follow the YouTube link ( to hear the song “Juana Azurduy” in the voice of the Argentinian singer Mercedes Sosa, honoring the valiant spirit of Juana Azurduy.

The taxonomic description and reconstruction of the phylogenetic relationships of Tropidurus azurduyae reflect on our efforts to advance the systematics of widely distributed complexes of cryptic species of Tropidurus. Because tropidurine fossils have not been discovered to date, we were unable to perform a safe chronological analysis to determine minimum ages for clades and species. However, the identification of endemic species restricted to the inter-Andean dry valleys from central and southern Bolivia and other seasonally dry tropical forests and open dry areas from South America allow us to expand the body of evidence supporting these areas as distinct biotic units. Furthermore, our results provide evidence against the Pleistocene Arc hypothesis, and call our attention to revisiting the biogeographic history of the dry areas of South America based on improved data sets and comparative analyses of a larger number of clades. For the first time, our results show with clarity that scenarios based exclusively on vicariance are unlikely to explain the complex biogeographic history of Tropidurus. Nevertheless, even if the distribution data and phylogenetic patterns recovered thus far allow us to rule out certain hypotheses in favor of others, determining the timeframe of the events involved in the diversification and biogeographic history of Tropidurus is crucial. Certainly, the incorporation of the time component (Donoghue and Moore, 2003) remains as a major challenge for us to fully understand the evolutionary history of this lizard clade (Carvalho et al., 2013). 

 André L. G. Carvalho (André Luiz Gomes), Luis Rolando Rivas, Ricardo Céspedes and Miguel Trefaut Urbano Rodrigues. 2018. A New Collared Lizard (Tropidurus, Tropiduridae) endemic to the western Bolivian Andes and Its Implications for Seasonally Dry Tropical Forests. American Museum Novitates. 3896; 1-56. DOI:  10.1206/3896.1


[Gastropoda • 2018] Aenigmatoconcha sumonthai • A New Helicarionid Land Snail (Helicarionidae: Durgellinae) from Chumphon Province, Southern Thailand

 Aenigmatoconcha sumonthai
C. Tumpeesuwan & S. Tumpeesuwan, 2018


 Aenigmatoconcha sumonthai, new species, is described from Tham Chang Phueak, a limestone range in Chumphon province, southern Thailand. The external morphology of the shell and soft parts, the genital system, and radula morphology were examined and compared with the type species of the genus, A. clivicola C. Tumpeesuwan & S. Tumpeesuwan, 2017 from northeastern Thailand. Externally the new species differs from A. clivicola in having a smaller shell, presence of black bands from the base of the long tentacles to the mantle edge, and both mantle shell lobes have numerous tiny white spots and irregular black marbling. The radula comprises approximately 22–35 transverse v-shaped rows of teeth, with each row having 11–150 unicuspid spatulated teeth. In the genital system, the penis is longer than the epiphallus and the base of the gametolytic sac is longer than the middle part. 

Key words. Aenigmatoconcha, mantle shell lobes, radula, karst, endemic taxa, disjunct distribution 

Fig. 2. Aenigmatoconcha sumonthai, new species, in natural habitat at the type locality; photographs taken on June 2017. A, two snails with the dorsal shell surface complately covered by the mantle shell lobes; B, two snails with mantle shell lobes retracted. (Photograph courtesy of Mr. Montri Sumontha).

Superfamily Helicarionoidea Bourguignat, 1877
Family Helicarionidae Bourguignat, 1877
Subfamily Durgellinae Godwin-Austen, 1888
Tribe Durgellini Godwin-Austen, 1888

Genus Aenigmatoconcha C. Tumpeesuwan & S. Tumpeesuwan, 2017
Type species. Aenigmatoconcha clivicola C. Tumpeesuwan & S. Tumpeesuwan, 2017

Aenigmatoconcha sumonthai, new species

Etymology. The species is named after the collector Montri Sumontha; the specific epithet “sumonthai” is from the family name “Sumontha”.

Diagnosis. The characters distinguishing Aenigmatoconcha sumonthai, new species, from A. clivicola are the colour patterns on mantle shell lobes and body, as well as morphology of radula and genital organs. Mantle shell lobes bear irregular black marbling pattern and numerous tiny white spots (Fig. 2A). Two black bands, each running from the base of a long tentacle (eyestalk) to mantle edge, are present (Fig. 2A). Central teeth of radula have a globose unicuspid cusp, with their size smaller than the 1st lateral teeth and only the distal halves of the globose cusps emerge from the 1st lateral teeth (Fig. 4C). The epiphallus is shorter than penis, and the middle part of the gametolytic sac in the new species is shorter than in A. clivicola (Fig. 5).

Chanidaporn Tumpeesuwan and Sakboworn Tumpeesuwan. 2018. Aenigmatoconcha sumonthai, A New Helicarionid Land Snail from Chumphon Province, Southern Thailand (Helicarionidae: Durgellinae). RAFFLES BULLETIN OF ZOOLOGY. 66; 170–176. 

[Herpetology • 2018] Taxonomic Review of the Rare Mexican Snake Genus Chersodromus (Serpentes: Dipsadidae), with the Description of Two New Species

Chersodromus rubriventris (Taylor, 1949)

in Canseco-Márquez, Ramírez-González & Campbell, 2018. 


Chersodromus is an endemic Mexican genus of snakes characterized by fused prefrontals shield. Only two species were previously known within the genus, C. liebmanni and C. rubriventris. We describe two new congeners, one from the Sierra Madre Oriental of northern Puebla and another from the Atlantic lowlands of the Chimalapas region in southeastern Oaxaca. These new species can be clearly differentiated on the basis of their morphology. Diagnostic characters distinguishing congeners include the number of dorsal scale rows, supralabials, and infralabials contacting anterior chinshields; whether or not the mental contacts the first pair of chinshields; and the coloration of the belly. We provide hemipenal descriptions of three species for which males are known.

Keywords: Reptilia, external morphology, Hemipenis, Puebla, Chimalapas, Oaxaca

Luis Canseco-Márquez, Cynthia G. Ramírez-González and Jonathan A Campbell. 2018. Taxonomic Review of the Rare Mexican Snake Genus Chersodromus (Serpentes: Dipsadidae), with the Description of Two New Species. Zootaxa. 4399(2);  151–169. DOI: 10.11646/zootaxa.4399.2.1


Tuesday, March 20, 2018

[Botany • 2018] Begonia adamsensis • A New Species (sect. Baryandra, Begoniaceae) from Luzon Island, the Philippines

Begonia adamsensis 

in Magtoto, Rubite & Austria, 2018.
   DOI:  10.11646/phytotaxa.343.3.10  


Begonia adamsensis from the northern part of Luzon Island is described as a new species endemic to the Philippines. This is the latest addition to the Begonia sect. Baryandra, making the total of Philippine begonias in this section to 56 species. It resembles Begonia hernandioides because its leaves are peltate, with a broad base, acuminate tip, nearly entire margin, and a glabrous peduncle; however, it differs significantly from B. hernandioides because of its broadly ovate red stipule, pubescent petiole, elliptic peltate leaf, pubescent abaxial lamina, and 4 perianth segments in the carpellate flower. Only about 200 individuals were found in a 100-m area that is being developed as a tourist spot in the locality, hence Begonia adamsensis is hereby proposed as critically endangered.

Keywords: BegoniaBaryandra, Philippines, Eudicots

Liezel M. Magtoto, Rosario R. Rubite and Celia Austria. 2018. Begonia adamsensis (sect. Baryandra, Begoniaceae), A New Species from Luzon Island, the Philippines. Phytotaxa. 343(3);  289–292.   DOI:  10.11646/phytotaxa.343.3.10 

[Paleontology • 2018] Arkansaurus fridayi • A New Ornithomimosaur from the Lower Cretaceous Trinity Group of Arkansas

Arkansaurus fridayi  Hunt & Quinn, 2018

Illustration by Brian Engh 

Whereas ornithomimosaurs (ostrich-mimic dinosaurs) are well known from Asia during the Early Cretaceous, they are less well known from this time in North America. Represented by a single specimen consisting of pedal elements, a new North American taxonArkansaurus fridayi, gen. et sp. nov., consists of a nearly complete right foot, recovered from the Lower Cretaceous (Albian–Aptian) Trinity Group of Arkansas. Arkansaurus fridayi can be distinguished from other ornithomimosaurs based on differentiated pedal unguals, a laterally compressed third metatarsal that is ovoid in proximal view, and a distal ungual with a very weak flexor tubercle, lacking spurs. The condition of this third metatarsal suggests that Arkansaurus fridayi is more basal than Asiatic ornithomimosaurs of similar age, but consistent with older North American forms. This specimen provides knowledge of a poorly understood radiation of ornithomimosaurs in Appalachia and is the only known saurischian dinosaurian fossil from the state of Arkansas.

FIGURE 3. Arkansaurus fridayi, UAM-74–16-1 to UAM-74–16-3, holotype,
articulated right metatarsals, in A, proximal and B, anterior views. Scale bar equals 10 cm. 

FIGURE 4. Arkansaurus fridayi, holotype, digital surface scans of pedal phalanges.
 UAM-74–16-5, phalanx II-1, in A, proximal, B, distal, C, extensor, D, flexor, E, lateral, and F, medial views.
UAM-74–16-4, phalanx III-1, in G, proximal, H, distal, I, extensor, J, flexor, K, lateral, and L, medial views.
UAM74–16-6, phalanx IV-1, in M, proximal, N, distal, O, extensor, P, flexor, Q, lateral, and R, medial views.
UAM-74–16-7, phalanx III-2, in S, proximal, T, distal, U, extensor, V, flexor, W, lateral, and X, medial views.
 UAM-74–16-8, large ungual, in Y, extensor, Z, lateral, AA, flexor, BB, medial, and CC, proximal views.
UAM-74–16-8, ungual, in DD, proximal, EE, extensor, FF, lateral, GG, flexor, and HH, medial views.
UAM-74–16-8, small ungual, in II, extensor, JJ, lateral, KK, flexor, and LL, medial views.
Scale bar equals 10 cm.

DINOSAURIA Owen, 1842 
SAURISCHIA Seeley, 1887 
THEROPODA Marsh, 1881; Gauthier, 1986 
ORNITHOMIMOSAURIA Barsbold, 1976; Lee et al., 2014 

ARKANSAURUS FRIDAYI, gen. et sp. nov.

Etymology—The genus is named for the state of Arkansas, where the specimen was discovered. The species name is in honor of Joe B. Friday, who discovered the remains in 1972.



Arkansaurus fridayi currently is one of the oldest basal ornithomimosaurs known from North America. Its occurrence in the southeastern portion of the North American continent is significant biogeographically, because most of the Early Cretaceous basal ornithomimosaurs were flourishing in Asia at the time, but are otherwise not well represented in North America. Further discoveries of similar ornithomimosaur taxa in North America will provide better understanding of additional, currently unknown, characters.

 ReBecca K. Hunt and James H. Quinn. 2018. A New Ornithomimosaur from the Lower Cretaceous Trinity Group of Arkansas. Journal of Vertebrate Paleontology. DOI:  10.1080/02724634.2017.1421209


[Crustacea • 2018] A New Yeti Crab Phylogeny: Vent Origins with Indications of Regional Extinction in the East Pacific

Map showing locations of kiwaids and the Cretaceous stem lineage fossil Pristinaspina gelasina in relation to land-masses and mid-ocean ridges.
in Roterman, Lee, Liu, et al., 2018.

The recent discovery of two new species of kiwaid squat lobsters on hydrothermal vents in the Pacific Ocean and in the Pacific sector of the Southern Ocean has prompted a re-analysis of Kiwaid biogeographical history. Using a larger alignment with more fossil calibrated nodes than previously, we consider the precise relationship between Kiwaidae, Chirostylidae and Eumunididae within Chirostyloidea (Decapoda: Anomura) to be still unresolved at present. Additionally, the placement of both new species within a new “Bristly” clade along with the seep-associated Kiwa puravida is most parsimoniously interpreted as supporting a vent origin for the family, rather than a seep-to-vent progression. Fossil-calibrated divergence analysis indicates an origin for the clade around the Eocene-Oligocene boundary in the eastern Pacific ~33–38 Ma, coincident with a lowering of bottom temperatures and increased ventilation in the Pacific deep sea. Likewise, the mid-Miocene (~10–16 Ma) rapid radiation of the new Bristly clade also coincides with a similar cooling event in the tropical East Pacific. The distribution, diversity, tree topology and divergence timing of Kiwaidae in the East Pacific is most consistent with a pattern of extinctions, recolonisations and radiations along fast-spreading ridges in this region and may have been punctuated by large-scale fluctuations in deep-water ventilation and temperature during the Cenozoic; further affecting the viability of Kiwaidae populations along portions of mid-ocean ridge.

Fig 1. Photographs of known kiwaid squat lobsters (“yeti crabs”).
A) Kiwa puravida modified from Thurber et al. [2011]; B) Kiwa sp. Galapagos Microplate; C) Kiwa araonae [2016]; D) Kiwa hirsuta modified from Muséum National D’Histoire Naturelle (MNHN) crustacean collection–credit Noémy Mollaret; E) Kiwa tyleri modified from Thatje et al. [2015]; (F) Kiwa sp. SWIR courtesy of David Shale. Scale bars are approximate and represent 10 mm. 

Fig 2. Map showing locations of kiwaids and the Cretaceous stem lineage fossil Pristinaspina gelasina in relation to land-masses and mid-ocean ridges.
 Kiwaid representations are: i) Kiwa puravida ii) Kiwa sp. GM, iii) Kiwa hirsuta, iv) Kiwa araonae v) Kiwa tyleri vi) Kiwa sp. SWIR. Land shapes and ridge positions are modified from the InterRidge Vents Database 2.1 static map ( Areas of mid-ocean ridge in light blue denote unexplored regions that may support Kiwaidae. Spreading ridge abbreviations are as follows: NEPR = Northern East Pacific Rise; SEPR = Southern East Pacific Rise; GR = Galapagos Rift; GM = Galapagos Microplate; PAR = Pacific-Antarctic Ridge; AAR = Australian-Antarctic Ridge; CR = Chile Rise; ESR = East Scotia Ridge; AmAR = American-Antarctic Ridge; SWIR = Southwest Indian Ridge; CIR = Central Indian Ridge; SEIR = Southeast Indian Ridge; MAR = Mid-Atlantic Ridge. Photograph of K. puravida modified from Thurber et al. [2011] and Kiwa hirsuta modified from Muséum National D’Histoire Naturelle (MNHN) crustacean collection–credit Noémy Mollaret

This study is an augmentation of Roterman et al. [2013] through the addition of more kiwaids, longer alignments and more fossil calibrations. Tree topologies produced here modify some of the inferences of the previous study. The sister-phyly of Kiwaidae and Chirostylidae within Chirostyloidea is placed in doubt, as are the previous inferences of a seep-to-vent evolutionary progression and a Northern Hemisphere origin for Kiwaidae. Current analyses do support the earlier inference for an East Pacific origin, however, and divergence estimates are broadly similar to previous analyses. Age estimates for the MRCA of Kiwaidae indicate an origin long after the PETM, around the Eocene-Oligocene boundary at a time of deep-water cooling and increased ventilation in the Pacific. Likewise, the rapid radiation of a newly defined Bristly clade appears synchronous with another transition to cooler and more ventilated conditions in the East Pacific during the Middle Miocene. The distribution, diversity, tree topology and divergence timing of vent-associated Kiwaidae in the Pacific is consistent with a pattern of regional extinctions, recolonisations and radiations along fast-spreading ridges over the last 40 million years. This pattern may have been punctuated by large-scale fluctuations in deep-water ventilation and temperature during the Cenozoic; further affecting the viability of Kiwaidae populations along large areas of mid-ocean ridge. The exploration of new vent and seep systems in the Pacific and beyond will help to better resolve the biogeographic history of Kiwaidae and provide new insights into the long-term resilience of metapopulations inhabiting deep-sea chemosynthetic ecosystems.

Christopher Nicolai Roterman, Won-Kyung Lee, Xinming Liu, Rongcheng Lin, Xinzheng Li and Yong-Jin Won. 2018. A New Yeti Crab Phylogeny: Vent Origins with Indications of Regional Extinction in the East Pacific.  PLoS ONE. 13(3): e0194696.  DOI: 10.1371/journal.pone.0194696

Monday, March 19, 2018

[Mammalogy • 2018] Systematics, Distribution and Ecological Analysis of Rodents in Jordan

Acomys russatus lewisi  Atallah, 1967

in Amr, Abu Baker, Qumsiyeh & Eid, 2018.


Distributional and ecological data were given to all rodents of Jordan. The rodent fauna of Jordan consists of 28 species with 20 genera in eight families (Cricetidae, Dipodidae, Gliridae, Hystricidae, Muridae, Myocastoridae, Sciuridae,and Spalacidae), including four introduced species.Keys for families and species were provided, along with diagnosis for each species and cranial illustrations for most species. Habitat preference and zoogeographic affinities of rodents in Jordan were analyzed, as well as their status and conservation.Threat categories and causes of threats on the rodents of Jordan were also analyzed.

        The distribution of rodents in Jordan represents a reflection of their global distribution ranges and habitat preferences. Species associated with the temperate forest of northern Jordan includes Sciurus anomalus and two wood mice, Apodemus mystacinus and A. flavicollis, while non-forested areas are represented by Nannospalax ehrenbergi and Microtus guentheri. Strict sand dwellers include Gerbillus cheesmani and G. gerbillus. Petrophiles associated with sandstone or black lava deserts are exemplified by Acomys russatus, A. r. lewsi, H. indica and S. calurus. Others including: Jaculus jaculus, G. nanus, G. henleyi, Meriones crassus, and M. libycus are all desert-adapted species with wider ranges of distribution where scarce vegetation, wadibeds, and marabs with clay, loess, or gravel surfaces provide foraging grounds and shelter. A single species, Gerbillus dasyurus, exhibits a wide range of distribution over diverse habitat types.

        The rodent fauna of Jordan consists of assemblages of different zoogeographical affinities. Nine, three, and seven were restricted or had most of its range within the Mediterranean, Irano-Turanian, and Saharo Arabian, respectively. Sciurus anomalus, Apodemus sp., Nannospalax ehrenbergi, and Microtus guentheri reached their most southern range of distribution in the Mediterranean regions of Jordan. The distribution of Gerbillus cheesmani extends from Asian deserts in India westwards into the Arabian Peninsula crossing Jordan as its most western range of distribution. Typical rodents of Saharo-Arabian affinities are represented by desert jerboas, gerbils, and jirds. North African species such as G. andersoni, G. gerbillus reached their most eastern distribution in southern Jordan. Both G. henleyi and G. nanus are widely-distributed species across North Africa reaching as far as India to the east, representing most northern outpost for these two species. Sekeetamys calurus is a nearly endemic to the Eastern Mediterranean region within southern Jordan and Sinai. Relicts are represented by Eliomys melanurus and Acomys russatus lewisi.

        Several threats affecting the rodent biodiversity in Jordan were identified including habitat loss and degradation, human disturbance and related activity, legislative and public awareness. The global conservation status of the rodents of Jordan according to the IUCN Red List include 22 species as least concern, one as near threatened (Allactaga euphratica), and one as data deficient (Nannospalax ehrenbergi). According to the regional assessment, one species is critically endangered, three species are considered endangered, one vulnerable.

Keywords: Mammalia, biodiversity, habitat preference, Jordan, rodents, zoogeography

Acomys russatus lewisi Atallah, 1967 

Zuhair S. Amr, Mohammad A. Abu Baker, Mazin Qumsiyeh and  Ehab Eid. 2018.  Systematics, Distribution and Ecological Analysis of Rodents in Jordan. Zootaxa. 4397(1);  1-94.   DOI:  10.11646/zootaxa.4397.1.1

[Mammalogy • 2017] Rediscovery of the Hispid Hare (Caprolagus hispidus) in Chitwan National Park, Nepal After Three Decades

Caprolagus hispidus (Pearson, 1839)

in Khadka, Yadav, Aryal & Aryal, 2017. 

The critical endangered hispid hare (Caprolagus hispidus) was first recorded as present in Chitwan, Bardiya and Shuklaphanta National Parks of Nepal in 1984. Since then, the species was recorded only in Bardiya and Suklaphanta National Parks. For more than three decades, it had not been observed in Chitwan National Park (CNP), where it was consequently considered extinct. In January 2016, a new recording for the hispid hare took place in CNP, placing that rare mammal again within CNP mammal assemblages. We reported the first photographic confirmation of the presence (30 Jan 2016) of the species in the CNP after 1984. The presence of hispid hare is confined to isolate patched of grassland of the national park. The population of the hispid hare is rapidly declining due to anthropogenic pressure and grassland fire from its distributed range (only found in Nepal, India, and Bhutan). Therefore, further study about their presence-absence, population status need to do throughout the grassland of the low land of Nepal including the newly rediscovering park.

Keywords: Hipsid hare, Chitwan National Park, new records, small mammals 

Hispid hare individual which was recorded in Chitwan National Park in 2016, as captured by camera-traps. The present recording is the 2nd observation of the species in the region since 1984.
photo: Bed Khadka

Bed Bahadur Khadka, Bhupendra Prasad Yadav, Nurendra Aryal and Achyut Aryal. 2017. Rediscovery of the Hispid Hare (Caprolagus hispidus) in Chitwan National Park, Nepal After Three Decades.   Conservation Science. 5(1); 10-12. DOI:  10.3126/cs.v5i1.18560

Small mammal thought to be extinct rediscovered in Nepal's national park via @physorg_com

Sunday, March 18, 2018

[Herpetology • 2018] Insular Diversification and Mountain Uplift were Complementary Drivers of Diversification in A Diverse Melanesian Lizard Radiation (Gekkonidae: Cyrtodactylus)

in Tallowin, Tamar, Meiri, et al., 2018.
  DOI: 10.1016/j.ympev.2018.03.020

• Australo-Papuan Cyrtodactylus geckos initially colonized and diversified within proto-Papuan islands in the early to mid-Miocene.
• Diversification was predominantly localized within distinct geological regions.
• Montane uplift played a critical role in the diversification of the regions Cyrtodactylus.

Regions with complex geological histories present a major challenge for scientists studying the processes that have shaped their biotas. The history of the vast and biologically rich tropical island of New Guinea is particularly complex and poorly resolved. Competing geological models propose New Guinea emerged as a substantial landmass either during the Mid-Miocene or as recently as the Pliocene. Likewise, the estimated timing for the uplift of the high Central Cordillera, spanning the length of the island, differs across models. Here we investigate how early islands and mountain uplift have shaped the diversification and biogeography of Cyrtodactylus geckos. Our data strongly support initial colonisation and divergence within proto-Papuan islands in the Early- to Mid-Miocene, with divergent lineages and endemic diversity concentrated on oceanic island arcs in northern New Guinea and the formerly isolated East-Papuan Composite Terrane. At least four lineages are inferred to have independently colonised hill- and lower-montane forests, indicating that mountain uplift has also played a critical role in accumulating diversity, even in this predominantly lowland lineage. Our findings suggest that substantial land in northern New Guinea and lower-montane habitats date back well into the Miocene and that insular diversification and mountain colonisation have synergistically generated diversity in the geologically complex Papuan region.

Keywords: biogeography; geology; Papuan region; time calibration

Oliver J.S. Tallowin, Karin Tamar, Shai Meiri, Allen Allison, Fred Kraus, Stephen J. Richards and Paul M. Oliver. 2018.  Insular Diversification and Mountain Uplift were Complementary Drivers of Diversification in A Diverse Melanesian Lizard Radiation (Gekkonidae: Cyrtodactylus).  Molecular Phylogenetics and Evolution. DOI: 10.1016/j.ympev.2018.03.020

[Arachnida • 2018] Repeated Diversification of Ecomorphs in Hawaiian Stick Spiders, Ariamnes spp.

Gillespie, Benjamin, Brewer, et al., 2018.

• Hawaiian stick spiders show adaptive radiation with repeated evolution of ecomorphs
• This phenomenon is found in only a few adaptive radiations of island insectivores
• Camouflage against a finite set of predators and wandering habit play key roles
• Limited pathways for the development of color contribute to deterministic evolution

Insular adaptive radiations in which repeated bouts of diversification lead to phenotypically similar sets of taxa serve to highlight predictability in the evolutionary process. However, examples of such replicated events are rare. Cross-clade comparisons of adaptive radiations are much needed to determine whether similar ecological opportunities can lead to the same outcomes. Here, we report a heretofore uncovered adaptive radiation of Hawaiian stick spiders (Theridiidae, Ariamnes) in which different species exhibit a set of discrete ecomorphs associated with different microhabitats. The three primary ecomorphs (gold, dark, and matte white) generally co-occur in native forest habitats. Phylogenetic reconstruction mapped onto the well-known chronosequence of the Hawaiian Islands shows both that this lineage colonized the islands only once and relatively recently (2–3 mya, when Kauai and Oahu were the only high islands in the archipelago) and that the distinct ecomorphs evolved independently multiple times following colonization of new islands. This parallel evolution of ecomorphs matches that of “spiny-leg” long-jawed spiders (Tetragnathidae, Tetragnatha), also in Hawaii. Both lineages are free living, and both have related lineages in the Hawaiian Islands that show quite different patterns of diversification with no evidence of deterministic evolution. We argue that repeated evolution of ecomorphs results from a rugged adaptive landscape, with the few peaks associated with camouflage for these free-living taxa against the markedly low diversity of predators on isolated islands. These features, coupled with a limited genetic toolbox and reduced dispersal between islands, appear to be common to situations of repeated evolution of ecomorphs.

Figure 2. Ecological Forms of the Hawaiian Ariamnes Colored boxes around images show the different ecomorphs: matte white, dark, and gold.
 (A) Ariamnes huinakolu; Kauai, Makalehas; July 2008. (B) A. sp.; Kauai, Pihea; November 2016. (C) A. kahili; Kauai, Wailua River; November 2016. (D) A. sp.; Oahu, Pahole; August 2008. (E) A. makue; Oahu, Kaala; November 2016. (F) A. uwepa; Oahu, Poamoho; November 2016. (G) A. corniger; East Maui; November 2016. (H) A. laau; East Maui; July 2013. (I) A. sp.; Molokai; November 2016. (J) A. waikula on web of Orsonwelles; Hawaii; July 2013. (K) A. hiwa; Hawaii; July 2014. (L) A. waikula; Hawaii, Saddle Road; July 2013.

Note that all of the gold forms—(C), (F), (I), and (L)—can exhibit color polymorphism, with red superimposed on the gold, as shown in (I). Photo credits: G. Roderick, (A–J), A. Rominger, (K), D. Cotoras, (L). Insets (B1, F1, and G1) show details of the guanine structure of the respective forms.

Ariamnes corniger, a stick spider from East Maui, Hawaiian Archipelago. This white matte ecomorph is cryptic against lichen.
 photo: George Roderick

Gold Molokai spider.
photo: George Roderick

An undescribed species of Ariamnes from Kauai, Hawaiian Archipelago. It is an example of the dark ecomorph.
photo: George Roderick 

Rosemary G. Gillespie, Suresh P. Benjamin, Michael S. Brewer, Malia Ana J. Rivera and George K. Roderick. 2018.  Repeated Diversification of Ecomorphs in Hawaiian Stick Spiders. Current Biology. DOI: 10.1016/j.cub.2018.01.083

How brightly colored spiders evolved on Hawaii again and again... and again   @physorg_com