Thesis (Ph.D. (Environmental Science))--North-West University, Potchefstroom Campus, 2007.

A total of 782 sea slug species (opisthobranch molluscs) within 161 genera, 56 families, and 7 orders are authentically recorded from Taiwan¡¦s Exclusive Economic Zone. Among these species, 459 species (58.7 %) are identified to species level and the other 323 species (41.3 %) are undescribed species. In terms of the whole Opisthobranchia fauna of the tropical western Pacific Ocean, approximately 1000 species are expected from Taiwan¡¦s EEZ. As most of the previous surveys on within-area species diversity were carried out in daytime, diel variation (i.e., day and night) in the species composition of sea slugs has been neglected. In order to assess whether such estimations for community diversity based only on daytime surveys are accurate, I undertook replicated diel surveys for 12 consecutive months (from December 2009 to November 2010) at Shilang Marine Reserve, Green Island (Lyudao), Taiwan. Phyllidiella pustulosa was observed most often during the daytime surveys, while Tritonia sp. 1 (an undescribed species) was the most abundant species at night. The results showed the species composition was clear different. During the field surveys, I found the difficult to identify the phyllidiid nudibranchs. Hence, I search for the additional taxonomic characters for phyllidiid nudibranchs base on integumentary spicules and gene sequences (COI and 16S genes). The results showed the spicules characters might provide the character to distinguish the Phyllidiella from other phyllidiid genera, but they were not informative at the species level. The results on molecular phylogeny showed that taxonomic status (both at the species and generic levels) of most phyllidiid genera, except Phyllidiella, received strong supports from COI gene and 16S gene. In contrast, each Phyllidiella species did not form a clade (suggesting the possibility of over estimating the species number in this genus). Finally, I described and illustrated three distinctive new species of Tambja (Nudibranchia: Polyceridae) from Taiwan and Australia. Among these three species, two of them were collected from Australia the other was collected from Taiwan. Tambja dracomus sp. nov. which is only distribution in cool temperate coastal waters in southeastern Australia and northern New Zealand; T. caeruleocirrus sp. nov. which is distributed in warm temperate coastal waters in eastern Australia, southeast Pacific Ocean. Tambja pulcherrima sp. nov. is widely distributed throughout the tropical, subtropical and warm temperate waters in western Pacific Ocean from Japan to northern New Zealand.

The linguliform brachiopod fauna from the Stephen Formation have long been thought to be very species poor and only consist of a few genera, but new discoveries from lime-stone beds in the “thick” Stephen Formation shows that this is not the case. The species described herein, Kyrshabaktella cf. tatjanae and Ceratreta hansi sp. nov., are two new additions to described species and genera of the area.The specimens come from a 0.6 meters thick limestone bed, approximately 17 meter above the base of the formation in the Canadian Rocky Mountains, British Columbia, Yoho National Park a few kilometers SSE from Odaray Mountain. The specimens where retained from the rock by dissolution in diluted formic acid for a few days and later coated with a palladium-gold alloy and photographed under a Scanning Electron Microscope (SEM).In addition to the widen knowledge that these specimens of K. cf. tatjanae and C. hansi brings to the paleoecology of the area the two species also expands the knowledge of their families and genera. The coarse filae ornamentation on the exterior shell of K. cf. tatjanae requires the revision of the diagnosis of the family Kyrshabaktellidae and the discovery of the new species C. hansi expands the stratigraphic range of the genus Ceratreta to the middle Cambrian. / Detta arbete behandlar arterna Kyrshabaktella cf. tatjanae och Ceratreta hansi sp. nov. från den ’tjocka’ Stephenformationen. Tidigare har området ansetts vara väldigt art- och släktfattigt på linguliforma brachiopoder. Nya fynd av Caron m.fl. (2010, 2014) visar på att så inte är fallet, och de fynd som behandlas här styrker den bilden. Fynden kommer från ett kalkstenslager beläget ca 17 meter upp i sekvensen på den ’tjocka’ Stephenformationen. Lagret har visat sig vara väldigt rikt på fossil. Med hjälp av dessa exemplar av K. cf. tatjanae har diagnosen av familjen Kyrshabaktellidae kunnat ändras, från att inte ha haft några utsmyckningar alls på de vuxna skalen till att kunna ha bland annat grovt koncentriska ornament (s.k. filae). Detta arbete och dessa nya fynd ska sprida ytterligare ljus över området. Förhoppningen är att denna ska hjälpa till att ge ny kunskap om områdets paleoekologi samt arterna och släktenas geografiska utbredning.Fossilen har separerats från kalkstenen genom att låta stufferna dra i utspädd myrsyra några dagar, tills kalken är upplöst. Fossilen har belagts med en palladium-guld legering och fotograferats med hjälp av ett svepelektronmikroskop (SEM).Syftet med arbetet är att göra en taxonomisk beskrivning av nya exemplar av brachiopodfossil från Stephenformationen.

Of the 430+ extant species of Gyrodactylus, ectoparasitic monogenetic flukes of aquatic vertebrates, Gyrodactylus salaris Malmberg, 1957 is arguably the most well-known. Following the introduction of this species into Norway in the 1970s with consignments of infected Atlantic salmon smolts, Salmo salar L., this species has had a devastating impact on the Norwegian Atlantic salmon population, decimating wild stocks in over 40 rivers. Gyrodactylus salaris is the only OIE (Office International des Epizooties) listed parasitic pathogen of fish and has been reported from 19 countries across Europe, though many of these records require confirmation. The UK, Ireland and some selected watersheds in Finland are currently recognised as G. salaris-free states; however, the threat that this notifiable parasite poses to the salmon industry in the UK and Ireland is of national concern. Current British contingency plans are based on the assumption that if G. salaris were to be introduced, the parasite would follow similar dynamics to those on salmonid stocks from across Scandinavia, i.e. that Atlantic strains of Atlantic salmon would be highly susceptible to infection, with mortalities resulting; that brown trout, Salmo trutta fario L., would be resistant and would lose their infection in a relatively short period of time; and that grayling, Thymallus thymallus (L.), would also be resistant to infection, but would carry parasites, at a low level, for up to 143 days. Two of the objectives of this study were to confirm the current distribution of G. salaris across Europe, and then, to investigate the relative susceptibility of British salmonids to G. salaris, to determine whether they would follow a similar pattern of infection to their Scandinavian counterparts or whether, given their isolation since the last glaciation and potential genetic differences, they would exhibit different responses. It has been almost six years since the distribution of G. salaris across Europe was last evaluated. Some of the European states identified as being G. salaris-positive, however, are ascribed this status based on misidentifications, on partial data resulting from either morphological or molecular tests, or according to records that have not been revisited. Additional Gyrodactylus material from selected salmonids was obtained from several countries to contribute to current understanding regarding the distribution of G. salaris across Europe. From the work conducted in the study, G. salaris is reported from Italy for the first time, alongside three other species, and appears to occur extensively throughout the central region without causing significant mortalities to their rainbow trout, Oncorhynchus mykiss (Walbaum), hosts. The analysis of archive material from G. salaris-positive farms would suggest that G. salaris has been in the country for at least 12 years. Material obtained from rainbow trout from Finland and Germany was confirmed as G. salaris supporting existing data for these countries. No specimens of G. salaris, however, were found in the additional Gyrodactylus material obtained from Portuguese and Spanish rainbow trout, only Gyrodactylus teuchis Lautraite, Blanc, Thiery, Daniel et Vigneulle, 1999, a morphologically similar species was found. Gyrodactylus salaris is now reported from 23 out of ~50 recognised states throughout Europe, only 17 of these however, have been confirmed by either morphology or by an appropriate molecular test, and only ten of these records have been confirmed by a combination of both methods. To assess the susceptibility of English and Welsh salmonids to G. salaris, a number of salmonid stocks of wild origin, were flown to the Norwegian Veterinary Institute (NVI) in Oslo, where they were experimentally challenged with G. salaris. Atlantic salmon from the Welsh River Dee, S. trutta fario from the English River Tyne and T. thymallus from the English River Nidd, raised from wild stock in government hatcheries, were flown out and subsequently challenged with G. salaris haplotype A. After acclimation, each fish was infected with ~50–70 G. salaris and marked, so that parasite numbers on individual fish could be followed. The dynamics on individual fish were followed against a control (Lierelva Atlantic salmon). The experiment found that the number of G. salaris on S. salar from the River Dee continued to rise exponentially to a mean intensity (m.i.) of ~3851 G. salaris fish-1 (day 40 post-infection). These salmon were highly susceptible, more so than the Norwegian salmon control (m.i. ~1989 G. salaris fish-1 d40 post-infection) and were unable to regulate parasite numbers. The S. trutta fario and T. thymallus populations, although initially susceptible, were able to control and reduce parasite burdens after 12 (m.i. ~146 G. salaris fish-1) and 19 (m.i. ~253 G. salaris fish-1) days, respectively when peak infections were seen. Although the latter two hosts were able to limit their G. salaris numbers, both hosts carried infections for up to 110 days (i.e. when the experiment was terminated). The ability of S. trutta fario and T. thymallus to carry an infection for long periods increases the window of exposure and the potential transfer of G. salaris to other susceptible hosts. The potential role that brown trout may play in the transmission and spread of G. salaris in the event of an outbreak, needs to be considered carefully, as well as the interpretation of the term “resistant” which is commonly used when referring to brown trout’s susceptibility to G. salaris. The current British surveillance programmes for G. salaris are focused on the screening of Atlantic salmon and on the monitoring of the rainbow trout movements. The findings from this study demonstrate that G. salaris can persist on brown trout for long periods, and suggest that brown trout sites which overlap with Atlantic salmon or rainbow trout sites are also included within surveillance programmes and that the role that brown trout could play in disseminating infections needs to be factored into contingency/management plans. Throughout the course of the study, a number of parasite samples were sent to the Aquatic Parasitology Laboratory at Stirling for evaluation. Some of these samples represented Gyrodactylus material that were associated with fish mortalities, but the species of Gyrodactylus responsible appeared to be new to science. A further aspect of this study was, therefore, to investigate these Gyrodactylus related mortalities in aquaculture stock and to describe the species found in each case, which may represent emerging pathogens. The two new species, Gyrodactylus orecchiae Paladini, Cable, Fioravanti, Faria, Di Cave et Shinn, 2009 and Gyrodactylus longipes Paladini, Hansen, Fioravanti et Shinn, 2011 on farmed gilthead seabream, Sparus aurata L., were collected from several Mediterranean farms. The finding of G. orecchiae in Albania and Croatia was associated with 2–10% mortality of juvenile stock and represents the first species of Gyrodactylus to be formally described from S. aurata. Subsequently, G. longipes was found in Bosnia-Herzegovina and Italy, and at the Italian farm site, it occurred as a mixed infection with G. orecchiae, but these infections did not appear to result in any loss of stock. Unconfirmed farm reports from this latter site, however, suggest that a 5–10% mortality of juvenile S. aurata was also caused by an infection of Gyrodactylus, which is suspected to be G. longipes. Additional samples of Gyrodactylus from a gilthead seabream farm located in the north of France have been morphologically identified as G. longipes, extending the geographical distribution of this potentially pathogenic species to three countries and three different coasts. In addition to these samples, some specimens of Gyrodactylus from a Mexican population of rainbow trout were sent for evaluation.

Water is a scarce and precious resource in South Africa. Not only is the quality and quantity of water available limited by climatic conditions but these resources are often impacted by domestic and industrial effluents, as well as run-off from agriculture. Monitoring the aquatic environment helps to determine the impact of various pollutants. Chemical monitoring, important as it is, can only at best give a "snapshot" of water quality at a particular moment in time. Biomonitoring in particular forms a vital part of monitoring programmes as it gives a time integrated reflection of a particular pollutant or group of pollutants on the ecosystem. Although diatoms have long been studied in South Africa, as well as being used in the past to indicate water quality, the current suite of bioindicator organisms used in this country has not until recently included diatoms, or any autotrophic organisms for that matter. This body of work is presented with the aim of facilitating the use of diatoms as bioindicators of water quality in South Africa. Methods for the collection, preparation and analysis of diatoms have been collated and standardized. A number of European and other indices have been tested in diverse localities for use in indicating recent and historical water quality. The impact of diffuse mine effluent on diatom community structure has also been discussed. A new species common in impacted waters (i.e. a potential indicator species for these conditions) has been described and a guide to the common diatoms of South Africa is presented which, it is hoped, will be of use to those who wish to commence with a study of South Africa's diatom flora. The results of this study show that diatom indices are successful in reflecting both current and past water quality in South Africa. This result justifies the inclusion of diatoms with the current suite of bioindicator organisms as well as in national monitoring initiatives such as the River Health Programme. Concluding comments underline the importance of using diatoms as indicators, not only of water quality, but also as indicators of aquatic microorganism biodiversity, or loss thereof. The need for continued research in the fields of diatom ecology and taxonomy is also highlighted. / Thesis (Ph.D. (Environmental Science))--North-West University, Potchefstroom Campus, 2007.

Dictyostelids (Amoebozoa) are a group of social amoebae consisting of approximately 150 species, which are found in terrestrial habitats worldwide. They are divided into eight major clades based on molecular phylogeny, and within these clades are many species complexes. Some species are seemingly cosmopolitan in distribution, while others are geographically restricted. In this thesis dictyostelids were recovered from high latitude habitats (soils in Sweden and Iceland) as well as from the soles of shoes. Morphological characters and DNA sequence analyses were used to identify isolates that were recovered and delimit new species, as well as to investigate the monophyly of Dictyostelium aureostipes. Nine species were reported from Northern Sweden and four from Iceland. Among the isolates recorded in Sweden were two new species, described as D. barbibulus and Polysphondylium fuscans. P. fuscans was among the four species recovered from footwear, contributing evidence for anthropogenic transport of dictyostelids. Ecological patterns were assessed using linear regression and generalized linear models. The ecological analyses of dictyostelids recovered from Iceland indicate that these organisms are most frequently found in soils of near-neutral pH, but also exhibit a species richness peak in moderately acidic soils. These analyses indicate that in Iceland dictyostelid species richness decreases with altitude, and in the northern hemisphere the species richness increases with decreasing latitude. A three-region analysis of the D. aureostipes species complex indicated that this species is in fact made up of at least five phylogenetically distinct clades, and in light of this the group is in need of taxonomic revision. These results indicate that the dictyostelid species richness is higher than previously known, especially in high-latitude regions, and that even seemingly well-defined species may harbour cryptic diversity. Presently, species ranges may be expanding via anthropogenic dispersal but despite this, the dictyostelids are found to exhibit biogeographic trends well known from macroorganisms, such as a latitudinal gradient of species richness.

Water is a scarce and precious resource in South Africa. Not only is the quality and quantity of water available limited by climatic conditions but these resources are often impacted by domestic and industrial effluents, as well as run-off from agriculture. Monitoring the aquatic environment helps to determine the impact of various pollutants. Chemical monitoring, important as it is, can only at best give a "snapshot" of water quality at a particular moment in time. Biomonitoring in particular forms a vital part of monitoring programmes as it gives a time integrated reflection of a particular pollutant or group of pollutants on the ecosystem. Although diatoms have long been studied in South Africa, as well as being used in the past to indicate water quality, the current suite of bioindicator organisms used in this country has not until recently included diatoms, or any autotrophic organisms for that matter. This body of work is presented with the aim of facilitating the use of diatoms as bioindicators of water quality in South Africa. Methods for the collection, preparation and analysis of diatoms have been collated and standardized. A number of European and other indices have been tested in diverse localities for use in indicating recent and historical water quality. The impact of diffuse mine effluent on diatom community structure has also been discussed. A new species common in impacted waters (i.e. a potential indicator species for these conditions) has been described and a guide to the common diatoms of South Africa is presented which, it is hoped, will be of use to those who wish to commence with a study of South Africa's diatom flora. The results of this study show that diatom indices are successful in reflecting both current and past water quality in South Africa. This result justifies the inclusion of diatoms with the current suite of bioindicator organisms as well as in national monitoring initiatives such as the River Health Programme. Concluding comments underline the importance of using diatoms as indicators, not only of water quality, but also as indicators of aquatic microorganism biodiversity, or loss thereof. The need for continued research in the fields of diatom ecology and taxonomy is also highlighted. / Thesis (Ph.D. (Environmental Science))--North-West University, Potchefstroom Campus, 2007.

Orientador: Ricaro Cardoso Benine / Resumo: A subfamília Stethaprioninae foi proposta por Eigenmann, 1907, e é distinguido dos demais representantes de Characidae por apresentar porte pequeno, corpo alto e comprimido, com um espinho ósseo localizado à frente do primeiro raio da nadadeira dorsal e pela presença de ganchos ósseos distribuídos de maneira assimétrica na nadadeira anal de machos maduros; esses dois últimos caracteres parecem ser sinapomórficos e sustentam a monofilia do grupo. A revisão taxonômica das espécies de Stethaprioninae foi realizada, e nove espécies novas foram descritas por meio da análise de material depositado em coleções ictiológicas. As descrições foram feitas a partir da análise de aproximadamente 2.500 exemplares, dos quais foram tomadas 44 variáveis morfométricas e 14 merísticas, além de dados osteológicos e padrão de colorido. Como resultados, foram consideradas válidas e redescritas 13 espécies: Poptella brevispina, P. compressa, P. longipinnis, P. paraguayensis, Orthospinus franciscensis, Stethaprion erythrops, S. crenatum, Brachychalcinus copei, B. nummus, B. Orbicularis, B. parnaibae, B. retrospina, e B. reisi; além da descrição de nove novas espécies. Orthopinus é um gênero monotípico e endêmico da bacia do rio São Francisco. Stethaprion apresenta duas espécies distribuídas na bacia do rio Amazonas e foi acresentado em nosso trabalho uma nova característica autapormórfica desse gênero, que é a presença de escamas na nadadeira adiposa. Para Poptella, foram diagnosticadas sete espécies... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The subfamily Stethaprioninae was proposed by Eigenmann, 1907, and is distinguished from the other representatives of Characidae because of its small size, tall, compressed body, and a bony spine located in front of the first ray of the dorsal fin and the presence of bony hooks distributed asymmetrical way in the anal fin of mature males; these last two characters are synapomorphic and support the group monophyly. The taxonomic revision of the species of Stethaprioninae was carried out, and nine new species were described through the analysis of deposited material in ichthyological collections. The descriptions were made from the analysis of approximately 2,500 specimens, of which 44 morphometric and 14 meristic variables were taken, in addition to osteological data and color pattern. As a result, 12 species were redescribed: Poptella brevispina, P. compressa, P. longipinnis, P. paraguayensis, Orthospinus franciscensis, Stethaprion erythrops, S. crenatum, Brachychalcinus copei, B. nummus, B. orbicularis, B. parnaibae,B. retrospina, and B. reisi, in addition to the description of ten new species. Orthospinus is a monotypic and endemic genus of the São Francisco river basin. Stethaprion presents two species distributed in the basin of the Amazon River, and is characterized mainly by the presence of scales in the adipose fin, being indicated in our work as an autopormorphic feature of this genus. For Poptella, seven new species were diagnosed, of which three are distributed in t... (Complete abstract click electronic access below) / Doutor

Os gêneros Hebanthe Mart. e Pfaffia Mart. pertencem à família Amaranthacaeae, atualmente representada por 170 gêneros e 2.000 espécies, concentradas nas regiões tropicais e subtropicais da América e África. No Brasil ocorrem 20 gêneros e 100 espécies. A presente tese trata do estudo taxonômico e fitogeográfico dos gêneros Hebanthe e Pfaffia no Brasil. A tese consiste de cinco capítulos: 1) “O gênero Pfaffia Mart. (Amaranthceae) no Brasil”. Foram confirmadas 20 espécies e dois nomes foram considerados sinônimos. São apresentadas descrições dos táxons, ilustrações, chaves analíticas, bem como dados de fenologia, hábitat e distribuição geográfica. 2) “Novas espécies de Pfaffia Mart. para o Brasil”. Dois artigos descrevendo as espécies novas de Pfaffia são apresentados. a) Pfaffia siqueiriana, b) Pfaffia cipoana e Pfaffia rupestris 3) “O gênero Hebanthe Mart. (Amaranthaceae) no Brasil”. Foram confirmadas seis espécies e sete nomes foram considerados sinônimos. São apresentadas descrições dos táxons, ilustrações, chave analítica, bem como dados de fenologia, hábitat e distribuição geográfica. 4) “Fitogeografia das espécies brasileiras de Pfaffia Mart. (Amaranthaceae)”. A província biogeográfica do Cerrado apresenta a maior riqueza com 19 espécies, sendo o estado de Minas Gerais considerado o centro de diversidade e endemismo do gênero. As espécies apresentam padrões de distribuição desde amplos até endêmicos. 5) “Análise da distribuição geográfica dos táxons brasileiros de Hebanthe Mart. (Amaranthaceae)”. A riqueza de espécies está concentrada em três províncias biogeográficas: Atlântica, Cerrado e Paranaense com quatro táxons em cada uma. São apresentados dois padrões de distribuição: amplo sul-americano e amplo brasileiro. / The genera Hebanthe Mart. and Pfaffia Mart belong, to the Amarathaceae, nowadays represented by 170 genus and 2.000 species, concentrated in the tropical and subtropical regions of the America and Africa. In the Brazil ca 20 genera and 100 species can be found. The thesis consists of five chapters: 1) “The genus Pfaffia Mart. (Amaranthaceae) in Brazil”. Tweenty species were confirmed and two names were considered as synonyms. Morphological descriptions, illustrations, analytical keys and also data about fenology, habitat and geographical distribution are presented. 2) “New species of Pfaffia Mart. in Brazil”. Two articles describing new species of Pfaffia described presented in this chapter. a) Pfaffia siqueiriana, b) Pfaffia cipoana and Pfaffia rupestris. 3) “The genus Hebanthe Mart. (Amaranthaceae) in Brazil”. Six species are confirmed, seven names were considered as synonyms. Morphological descriptions, illustrations, analytical key and also data related to fenology, habitat and geographical distribution are presented. 4) “Phytogeography of the Brazilian species of Pfaffia Mart. (Amaranthaceae)”. The biogeographic province of the “Cerrado” present, highest richness, with 19 species. The State of Minas Gerais can be considered the center of diversity and endemism of the genus. The species present distribution ranging from wide to endemic. 5) “Analysis of the geographic distribution of the Brazilian taxa of Hebanthe Mart. (Amaranthaceae)”. Hebanthe species richness is concentrated in three biogeographic provinces: “Atlântica”, “Cerrado” and “Paranaense” with four species each. Two distribution patterns, a wide South American and wide Brazilian are recognized.

This review was based on the taxonomic study of collections of specimens belonging to the genus Speocarcinus Stimpson, 1859, deposited at the Museum of Zoology, University of São Paulo (MZUSP), Department of Oceanography, Federal University of Pernambuco (DOUFPE) and the National Museum of Natural History, Smithsonian Institution (USNM). All species (S. amazonicus Brandão, Tavares & Coelho-Filho, 2010, S. carolinensis Stimpson, 1859, S. lobatus Guinot, 1969, S. granulimanus Rathbun, 1894, S. meloi D Incao & Silva, 1991, S . monotuberculatus Felder & Rabalais, 1986 and S. spinicarpus Guinot, 1969) currently assigned to the genus were studied, except the fossil species S. berglundi Tucker, Feldmann & Powell, 1994. The present study enabled to correct identification errors, faults and inaccuracies in descriptions and diagnoses of species. Upon completion of this work Speocarcinus includes nine species: S. berglundi, S. amazonicus, S. carolinensis, S. lobatus, S. granulimanus, S. meloi, S. monotuberculatus, S. spinicarpus and Speocarcinus sp. n. Speocarcinus amazonicus and Speocarcinus sp. n. comes from the brazilian coast, and has been mistakenly attributed to S. carolinensis. The geographical distribution of S.carolinensis is restricted to the region between North Carolina and the Gulf of Mexico and West Indies, not happening in Brazil so far. Currently two endemic species occur in Brazil: S. meloi and Speocarcinus sp. n. And one of them, S. meloi, has expanded its geographic north, occurring in Alagoas, Rio de Janeiro, São Paulo and Rio Grande do Sul / Fundação de Amparo a Pesquisa do Estado de Alagoas / A presente revisão taxonômica se baseou no estudo de coleções de exemplares pertencentes ao gênero Speocarcinus Stimpson, 1859, depositados no Museu de Zoologia da Universidade de São Paulo (MZUSP), no Departamento de Oceanografia da Universidade Federal de Pernambuco (DOUFPE) e no National Museum of Natural History, Smithsonian Institution (USNM). Todas as espécies (S. amazonicus Brandão, Tavares & Coelho-Filho, 2010, S. carolinensis Stimpson, 1859, S. lobatus Guinot, 1969, S. granulimanus Rathbun, 1894, S. meloi D Incao & Silva, 1991, S. monotuberculatus Felder & Rabalais, 1986 e S. spinicarpus Guinot, 1969) atualmente atribuídas ao gênero foram estudadas, exceto a espécie fóssil S. berglundi Tucker, Feldmann & Powell, 1994. O presente estudo possibilitou a correção de erros de identificação, falhas e imprecisões de descrições e diagnoses das espécies. Ao término deste trabalho Speocarcinus inclui nove espécies: S. berglundi, S. amazonicus, S. carolinensis, S. lobatus, S. granulimanus, S. meloi, S. monotuberculatus, S. spinicarpus e Speocarcinus sp. n. Speocarcinus amazonicus e Speocarcinus sp. n. provêm da costa brasileira, e têm sido, equivocamente, atribuídas a S. carolinensis. A distribuição geográfica de S. carolinensis é restrita à região compreendida entre a Carolina do Norte e o Golfo do México e Antilhas, não ocorrendo no Brasil até o momento. Atualmente duas espécies endêmicas ocorrem no Brasil: S. meloi e Speocarcinus sp. n. E uma delas, S. meloi, teve sua distribuição geográfica ampliada ao Norte, ocorrendo em Alagoas, Rio de Janeiro, São Paulo e Rio Grande do Sul.