scholarly journals Co-occurring cryptic species pose challenges for conservation: a case study of the African dwarf crocodile (Osteolaemusspp.) in Cameroon

Oryx ◽  
2014 ◽  
Vol 49 (4) ◽  
pp. 584-590 ◽  
Author(s):  
Nicole L. Smolensky

AbstractThe conservation status of threatened taxa may be obfuscated by the detection of cryptic species complexes, in both vertebrate and invertebrate species. African dwarf crocodiles (Osteolaemusspp.) are hunted throughout their range but their conservation status is unknown. Few population assessments have been carried out and there has been a taxonomic revision of the number of species in the genus. The similar morphologies ofOsteolaemus tetraspisandOsteolaemus osbornipose a challenge for conservation in Cameroon, where they are still managed as a single species. Nocturnal spotlight surveys were conducted in three regions during August–November 2010 and December 2011–February 2012 to provide population assessments ofO. tetraspisandO. osborniand raise awareness of the two species in Cameroon. The mean encounter rates ofO. tetraspisandO. osborniwere 1.02 ± SD 1.34 (65 individuals in 39 surveys) and 0.61 ± SD 0.38 (three in four surveys) crocodiles per km, respectively. TheO. tetraspispopulation comprised juveniles predominantly and had a male-biased sex ratio. The fewO. osbornidetected comprised both adults and juveniles. Both species are threatened in Cameroon, based on low encounter rates, young population structures and the threats of habitat loss and hunting pressure. This study provides distribution maps and serves as a baseline to quantify population trends and inform conservation strategies.

Parasitology ◽  
2008 ◽  
Vol 136 (2) ◽  
pp. 241-252 ◽  
Author(s):  
T. L. F. LEUNG ◽  
D. B. KEENEY ◽  
R. POULIN

SUMMARYRecent studies have shown that some digenean trematodes previously identified as single species due to the lack of distinguishing morphological characteristics actually consist of a number of genetically distinct cryptic species. We obtained mitochondrial 16S and nuclear ITS1 sequences for the redial stages of Acanthoparyphium sp. and Curtuteria australis collected from snails and whelks at various locations around Otago Peninsula, New Zealand. These two echinostomes are well-known host manipulators whose impact extends to the entire intertidal community. Using phylogenetic analyses, we found that Acanthoparyphium sp. is actually composed of at least 4 genetically distinct species, and that a cryptic species of Curtuteria occurs in addition to C. australis. Molecular data obtained for metacercariae dissected from cockle second intermediate hosts matched sequences obtained for Acanthoparyphium sp. A and C. australis rediae, respectively, but no other species. The various cryptic species of both Acanthoparyphium and Curtuteria also showed an extremely localized pattern of distribution: some species were either absent or very rare in Otago Harbour, but reached far higher prevalence in nearby sheltered inlets. This small-scale spatial segregation is unexpected as shorebird definitive hosts can disperse trematode eggs across wide geographical areas, which should result in a homogeneous mixing of the species on small geographical scales. Possible explanations for this spatial segregation of the species include sampling artefacts, local adaptation by first intermediate hosts, environmental conditions, and site fidelity of the definitive hosts.


Botany ◽  
2010 ◽  
Vol 88 (9) ◽  
pp. 787-809 ◽  
Author(s):  
Hyeok Jae Choi ◽  
J. Hugo Cota-Sánchez

The taxonomy, rarity, and conservation status of Allium  L. is revised for the Canadian prairie provinces, based on analyses of herbarium specimens and fieldwork. Five species are recognized: Allium schoenoprasum  L., A. geyeri S. Watson var. tenerum M.E. Jones, A. textile A. Nelson & J.F. Macbride, A. cernuum Roth, and A. stellatum Ker Gawler. Distribution maps and a key to species are provided, as well as complete descriptions of the species examined, including new illustrations, information on nomenclatural types, synonymies, and chromosomal and ecological data. A lectotype is designated for A. geyeri var. tenerum. In this study, A. geyeri var. geyeri reported from Alberta and Saskatchewan and ranked in these provinces as having rarity levels S2 and S1, respectively, by the Nature Conservancy, is excluded from the Canadian flora and the rare list of these provinces because it was misidentified from a herbarium specimen of A. textile. Allium tricoccum Solander in W. Aiton is regarded as a non-native species to Manitoba. The rarity and conservation status of Allium in the Canadian prairie provinces is as follows: (i) A. schoenoprasum, listed as S2 in Saskatchewan, is rare in Manitoba, although its rarity status has not been formally assessed in the province; (ii) A. geyeri var. tenerum is the rarest Allium taxon, with distribution restricted to the Waterton Lakes National Park areas of Alberta, and is currently listed as S2; and (iii) A. cernuum was re-evaluated and a rarity level of S1S2 was recommended for the species in Saskatchewan, particularly in its southwestern distributional habitat.


Phytotaxa ◽  
2017 ◽  
Vol 301 (1) ◽  
pp. 1 ◽  
Author(s):  
LUIZ HENRIQUE M. FONSECA ◽  
SIMONE MIRANDA CABRAL ◽  
MARIA DE FATIMA AGRA ◽  
LÚCIA G. LOHMANN

Dolichandra Cham. emend. L.G.Lohmann is a genus of Neotropical lianas in tribe Bignonieae (Bignoniaceae) that comprises nine species. It is centered in Paraguay, southern Brazil and northeastern Argentina, where six species occur and three are endemic. Species of Dolichandra are generally climbers of dry and wet lowland forests, also growing in swamps and gallery forest formations. The genus is characterized by four main synapomorphies: (i) stems with multiple dissected phloem wedges in cross-section, (ii) trifid and uncate tendrils, (iii) psilate and 3-colpate pollen, and (iv) capsules with four lines of dehiscense. Other features of the genus are the large and membranaceous calyces, dimorphic growth with the juvenile form attaching by its uncinate tendrils, lanceolate prophylls of the axillary buds, congested-cymose inflorescences, and a lobed nectary disk. In this taxonomic revision, we present detailed descriptions for all species recognized, taxonomic and nomenclatural comments, distribution maps and information on the habitat and distribution of each species, as well as information on their conservation status (i.e., IUCN categories), and illustrations of diagnostic characters. Thirty-five names are treated as synonyms, six of which are newly proposed. More specifically, Tecoma maximiliani Mart. ex DC. is synonymized under Dolichandra unguiculata (Vell.) L.G. Lohmann, Bignonia pseudounguis Desf., Bignonia unguis-cati var. radicans DC., and Macfadyena hassleri Sprague are synonymized under Dolichandra uncata (Andrews) L.G. Lohmann, while Bignonia tweediana Lindley and Dolichandra kohautiana Presl are synonymized under Dolichandra ungui-cati (L.) L.G. Lohmann. Lectotypes are proposed for 13 species names, namely Bignonia californica Brandegee, Bignonia gracilis G. Lodd., Bignonia inflata Griseb. Bignonia tweediana Lindley, Bignonia unguis-cati var. guatemalensis K. Schum. & Loes., Bignonia unguis-cati var. serrata Bureau & K. schum., Dolichandra cynanchoides Cham., Dolichandra fenzliana Miq. Macfadyena hassleri Sprague, Parabignonia steyermarkii Sandwith, Paradolichandra chodatii var. brachycalyx , Spathodea mollis and Tecoma maximiliani Mart. ex DC.


2019 ◽  
Author(s):  
Pilar Alda ◽  
Manon Lounnas ◽  
Antonio A. Vázquez ◽  
Rolando Ayaqui ◽  
Manuel Calvopiña ◽  
...  

AbstractCryptic species can present a significant challenge to the application of systematic and biogeographic principles, especially if they are invasive or transmit parasites or pathogens. Detecting cryptic species requires a pluralistic approach in which molecular markers facilitate the detection of coherent taxonomic units that can then be analyzed using various traits (e.g., internal morphology) and crosses. In asexual or self-fertilizing species, the latter criteria are of limited use. We studied a group of cryptic freshwater snails (genusGalba)from the family Lymnaeidae that have invaded almost all continents, reproducing mainly by self-fertilization and transmitting liver flukes to humans and livestock. We aim to clarify the systematics, distribution and phylogenetic relationships of these species with an integrative approach that includes morphology (shell and reproductive anatomy), molecular markers, wide-scale sampling across America, and data retrieved from GenBank (to include Old World samples). Our phylogenetic analysis suggests that the genusGalbaoriginated ca. 22 Myr ago and today comprises six clusters of species. Four of these clusters (G.truncatula,G.cubensis/viator,G.humilisandG.schirazensis) are morphologically cryptic and constitute species or species complexes with wide variation in their genetic diversity, geographic distribution and invasiveness. The other two clusters constitute a single species or a species complex (Galba cousini/meridensis) that demonstrate more geographically restricted distributions and exhibit an alternative morphology more phylogenetically derived than the cryptic one. Further genetic studies are required to clarify the status of bothG. cousini/meridensisandG.cubensis/viator. We emphasize that noGalbaspecies should be identified without molecular markers and that additional sampling is required, especially in North America, Eurasia and Africa to clarify remaining questions in systematics and biogeography. We also discuss several hypotheses that can explain crypsis inGalba, such as convergence and morphological stasis, and hypothesize a role for stabilizing selection in amphibious (rather than strictly freshwater) habitats.


PhytoKeys ◽  
2021 ◽  
Vol 177 ◽  
pp. 77-116
Author(s):  
Eric Y. Kataoka ◽  
Lúcia G. Lohmann

Martinella Baill. is a genus of Neotropical lianas in tribe Bignonieae (Bignoniaceae). The genus is monophyletic and well supported by morphological and molecular characters. Members of Martinella are characterized by a continuous interpetiolar ridge surrounding the stem, bilobed or 4–5-parted calyces, and minute triangular prophylls of the axillary buds. Generic circumscription remained unchanged since the description of the genus, although unclear species limits remained. Based on extensive fieldwork, herbarium work, and a molecular phylogenetic hypothesis for the genus, we here recognize five species of Martinella. Of these, three were recognized in earlier treatments for the genus, while two represent new species described here, Martinella lanuginosa Kataoka & L.G.Lohmann, sp. nov. and Martinella tomentosa Kataoka & L.G.Lohmann, sp. nov.Martinella iquitoensis A.Samp. is treated as a synonym of M. insculpta Sprague & Sandwith. In addition, one second-step lectotype is designated for Bignonia martini DC., and neotypes are designated for Doxantha longisiliqua Miers and Martinella gollmeri K.Schum. This work provides a full taxonomic treatment for Martinella, including a complete list of synonyms, morphological descriptions, illustrations, photographs, distribution maps, conservation status, and comments for all five species recognized.


2018 ◽  
Vol 25 (1) ◽  
pp. 19-43 ◽  
Author(s):  
Dhafer Ahmed Alzahrani ◽  
Enas Jameel Albokhari

The genera Tetraena Maxim. and Zygophyllum L. (Zygophyllaceae) present different morphological characters, viz. growth habit, leaf features, flower traits and fruit shape, and have a high diversity of species in Africa, Australia and Asia. Six species of Tetraena [T. alba (L.f.) Beier & Thulin, T. coccinea (L) Beier & Thulin, T. decumbens (Delile) Beier & Thulin, T. hamiensis (Schwein f.) Beier & Thulin, T. propinqua (Decne.) Ghaz. & Osborne and T. simplex (L.) Beier & Thulin], and one species of Zygophyllum (Z. fabago L.) have been identified in Saudi Arabia, most of which grow in sandy soils and saline habitats as shrubs and herbs. One new endemic variety (T. alba var. arabica Alzahrani & Albokhari) along with four new combinations [T. alba var. amblyocarpa (Baker) Alzahrani & Albokhari, T. hamiensis var. qatarensis (Hadidi ex Beier & Thulin) Alzahrani & Albokhari, T. hamiensis var. mandavillei (Hadidi ex Beier & Thulin) Alzahrnai & Albokhari, and T. propinqua subsp. migahidii (Hadidi ex Beier & Thulin) Alzahrani & Albokhari] are proposed. Descriptions, illustrations, distribution maps and a key for identification of the taxa are presented. Conservation status has been proposed for the new variety and combinations.Bangladesh J. Plant Taxon. 25(1): 19-43, 2018 (June)


Phytotaxa ◽  
2016 ◽  
Vol 264 (1) ◽  
pp. 1
Author(s):  
LAWRENCE M. KELLY ◽  
FRANK ALMEDA ◽  
PETER W. FRITSCH

A taxonomic revision of the Mexican and Central American members of Symplocos is presented. Thirty two species are recognized for the region. Two of the species belong to Symplocos sect. Hopea, and 30 are members of S. sect. Symplocos series Symplocos. The species of S. ser. Symplocos are easily distinguished from those of S. sect. Hopea by their connate petals that are adnate to the androecium distinctly beyond the base (versus connate and adnate at the base only), and filaments that are tangentially flattened in cross section and apically constricted (versus terete and not apically constricted). Of the 32 recognized species, ten are endemic to Mexico, 13 are endemic to Central America, two are shared between Central America and South America, seven are shared between Mexico and Central America, and one is shared among Mexico, Central America, and Cuba. One new species, S. nigridentata, is described from Mexico, and lectotypifications or neotypifications are provided for S. coccinea, S. coccinea var. hirta, S. costaricana, S. hartwegii, S. hartwegii var. opaca, S. limoncillo, S. prionophylla, S. pycnantha, S. schiedeana, S. serrulata, S. speciosa, and S. tomentosa. The revision includes keys, full synonymy, descriptions, illustrations for those species not already illustrated elsewhere, distribution maps and assignment of conservation status for all species, and a complete list of exsiccatae.


Phytotaxa ◽  
2017 ◽  
Vol 330 (1) ◽  
pp. 1 ◽  
Author(s):  
PETER B. HEENAN

A taxonomic revision of the cosmopolitan genus Cardamine is presented for New Zealand. Previous systematic research and the taxonomic history of Cardamine in New Zealand is reviewed, and a phylogenetic analysis of DNA sequences shows most of the species of Cardamine in New Zealand and Australia are closely related. Forty one taxa indigenous to New Zealand are recognised, with thirty-one species newly named and described, ten previously named taxa are accepted, including C. depressa with two subspecies and a new name is provided for one species. An additional four species are accepted as naturalised in New Zealand. Descriptions are presented for all taxa, along with information on distribution, habitats and conservation status. All taxa are illustrated, distribution maps provided, and a dichotomous key presented to assist with identification.


2020 ◽  
Vol 105 (2) ◽  
pp. 195-231
Author(s):  
Alicia Vicente ◽  
Mª Ángeles Alonso ◽  
Manuel B. Crespo

Biscutella L. ser. Biscutella (= Biscutella ser. Lyratae Malin.) comprises mostly annual or short-lived perennial plants occurring in the Mediterranean basin and the Middle East, which exhibit some diagnostic floral features. Taxa in the series have considerable morphological plasticity, which is not well correlated with clear geographic or ecologic patterns. Traditional taxonomic accounts have focused on a number of vegetative and floral characters that have proved to be highly variable, a fact that contributed to taxonomic inflation mostly in northern Africa. A detailed study and re-evaluation of morphological characters, together with recent phylogenetic data based on concatenation of two plastid and one nuclear region sequence data, yielded the basis for a taxonomic reappraisal of the series. In this respect, a new comprehensive integrative taxonomic arrangement for Biscutella ser. Biscutella is presented in which 10 taxa are accepted, namely seven species and three additional varieties. The name B. eriocarpa DC. is reinterpreted and suggested to include the highest morphological variation found in northern Morocco. Its treatment here accepts two varieties, one of which is described as new (B. eriocarpa var. riphaea A. Vicente, M. Á. Alonso & M. B. Crespo). In addition, the circumscriptions of several species, such as B. boetica Boiss. & Reut., B. didyma L., B. lyrata L., and B. maritima Ten., are revisited. Nomenclatural types, synonymy, brief descriptions, cytogenetic data, conservation status, distribution maps, and identification keys are included for the accepted taxa, with seven lectotypes and one epitype being designated here.


Author(s):  
P.H. Hoekstra ◽  
J.J. Wieringa ◽  
P.J.M. Maas ◽  
L.W. Chatrou

This taxonomic revision of the continental African species of Monanthotaxis (Annonaceae) includes 79 species and one variety. Thirteen new species (M. aestuaria, M. bidaultii, M. confusa, M. glabra, M. hexamera, M. mcphersonii, M. quasilanceolata, M. sterilis, M. submontana, M. suffruticosa, M. ursus, M. vulcanica and M. wieringae) are described and 5 new combinations (M. biglandulosa, M. kenyensis, M. ochroleuca, M. pynaertii and M. seretii) are made. The genus Monanthotaxis consists of lianas or lianescent shrubs. It occurs throughout forests in tropical Africa and the highest species diversity is found in the Western Central African rain forests. A key for flowering material is provided, just like a synoptic key including 45 characters. Topics included in the revision are the history of the taxonomy of Monanthotaxis, morphology, leaf anatomy, floral biology, distribution and habitat, phylogeny and finally ethnobotany and phytochemistry. Each species is fully described including synonymy, notes on distribution, habitat & ecology, vernacular names, uses and a preliminary IUCN conservation status. Distribution maps are provided for all species, illustrations for 48 species and photographs of 22 species. An index of exsiccatae and an index of the scientific names are included at the end.


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