Freshwater Shrimp Species Research Articles

Solomon’s Gold Mine: Description or redescription of 24 species of Caridina (Crustacea: Decapoda: Atyidae) freshwater shrimps from the Solomon Islands, including 11 new species.

Following recent (2014–2017) collections made in the Solomon Islands by the MNHN and the NGO ESSI, we provide a checklist of the species of amphidromous freshwater shrimps of the genus Caridina H. Milne Edwards, 1837 from this region. Using morphological as well as molecular data in an integrative taxonomic perspective, we found a total of 24 species, including 11 new for science, that are described or re-described, illustrated and discussed in relation to their habitat and distribution. Newly described species are Caridina barakoma sp. nov., C. choiseul sp. nov., C. intermedia sp. nov., C. maeana sp. nov., C. nana sp. nov., C. piokerai sp. nov., C. pisuku sp. nov., C. paratypus sp. nov., C. poarae sp. nov., C. sikipozo sp. nov. and C. turipi sp. nov. Caridina gueryi Marquet, Keith & Kalfatak, 2009 is re-validated as a species distinct from C. buehleri Roux, 1934. Lectotypes are designated for C. mertoni Roux, 1911 and C. papuana Nobili, 1905. Diagnoses for 6 informative species groups are provided: C. brevicarpalis group, C. gracilirostris group, C. nilotica group, C. typus group, C. serratirostris group and C. weberi group. A map of the species distribution in the Solomon Islands, as well as the phylogenetic relationships between the species and their relatives, are provided.

Effect of Addition of Cod Liver Oil in the Commercial Feed Protein Retention and Retention Energy Meat Giant Freshwater Prawn (Macrobrachium rosenbergii)

Prawns (Macrobrachiumrosenbergii) is one of the freshwater shrimp species native to Indonesia. Shrimp prawns are the most popular of all freshwater shrimp because of its large size and has a high economic value in both domestic market and abroad. Problems commonly encountered in the cultivation of prawns currently includes several factors such as water quality, disease and feed. Efforts that can be done is by feeding in sufficient quantity and quality and not excessive is a very decisive factor. Technical constraints on the level of farmers are limited in supply mains quality. Therefore, efforts are needed to tackle these problems by managing the stock of prawns parents. This study aims to determine the addition of cod liver oil on a commercial feed can increase protein retention and energy retention prawns (Macrobrachium rosenbergii). This research was carried out experimentally with a completely randomized design (CRD). The treatments were given a dose of cod liver oil 0% (control), and the treatment 1-4 using a 3% increase each treatment dose. Analysis of data using ANOVA followed by Duncan test. Based on the research results giving cod liver oil on a commercial feed effect on increasing protein retention and energy retention of lobster meat. Retention of the best protein found in 4 treatments with a dose of 12%, while the retention of the best energy contained in the second treatment with a dose of 6%.

Identification and in silico structural and functional analysis of a trypsin-like protease from shrimp Macrobrachium carcinus.

Macrobrachium carcinus (Linnaeus, 1758) is a species of freshwater shrimp widely distributed from Florida southwards to southern Brazil, including southeast of Mexico. In the present work, we identified a putative trypsin-like protease cDNA fragment of 736 nucleotides from M. carcinus hepatopancreas tissue by the 3′RACE technique and compared the deduced amino acid sequence to other trypsin-related proteases to describe its structure and function relationship. The bioinformatics analyses showed that the deduced amino acid sequence likely corresponds to a trypsin-like protease closely related to brachyurins, which comprise a subset of serine proteases with collagenolytic activity found in crabs and other crustacea. The M. carcinus trypsin-like protease sequence showed a global sequence identity of 94% with an unpublished trypsin from Macrobrachium rosenbergii (GenBank accession no. AMQ98968), and only 57% with Penaeus vannamei trypsin (GenBank accession no. CAA60129). A detailed analysis of the amino acid sequence revealed specific differences with crustacean trypsins, such as the sequence motif at the beginning of the mature protein, activation mechanism of the corresponding zymogen, amino acid residues of the catalytic triad and residues responsible for substrate specificity.

Culture model of Cherax quadricarinatus: Temporary shelter in shed and pond culture

The redclaw crayfish, Cherax quadricarinatus, is a valuable freshwater shrimp species with outstanding advantages and broad prospects for aquaculture. The culture of this crayfish has been gradually rising in the middle and lower sections of the Yangtze Plain. However, several problems such as short cultivation cycles, a lack of cultivation specifications, and low seedling survival rates are encountered when culturing this species in nontropical areas given that this particular crayfish is a tropical species. These conditions have hindered its development in the industry. Therefore, a scientific culture mode must be developed. This study explores the establishment of a culture model suitable for the characteristics of this crayfish: a temporary shelter used in shed and pond culture. The technology is described in terms of pond and shed construction, cleaning and disinfection, fertilization and water quality management, the cultivation of water grass, juvenile crayfish stocking, temporary shed shelter arrangements, pond culture management, disease and pathogen control, and harvesting. Results show that 1) the yield per hectare and survival rate of ponds with sheds were 2739.50 ± 307.53 kg ha−1 and 68.82% ± 4.23%, respectively, exceeding those of ponds with no sheds; 2) the highest yield and survival rate of ponds were measured as 3930.0 kg ha−1 and 77.73%, respectively (the shed area covered 220 m2, the temporary-keeping density was measured as 100 tails m−2, stocking occurred on April 15, 2019, the cultivation cycle lasted 182 days, and stocking density was measured as 87,300 tails ha−1); 3) the crayfish growout season ran from April to November. However, summer was the main growing season for the crayfish. After August, the growth rate decreased. In conclusion, the addition of sheds to temporary shelters provides a clear advantage in terms of both yields and survival rates. This culture model can meet cultivation demand in the middle and lower sections of the Yangtze Plain. Furthermore, the proportion of sheds in ponds should be increased, and stocking (in mid-April or earlier) and saling (appearance on the market in autumn) should occur earlier on. The cultivation cycle should be extended, and shed management should be the primary focus.

Two freshwater shrimp species of the genus Caridina (Decapoda, Caridea, Atyidae) from Dawanshan Island, Guangdong, China, with the description of a new species.

A faunistic and ecological survey was conducted to document the diversity of freshwater atyid shrimps of Dawanshan Island. Two species of Caridina that occur on this island were documented and discussed. One of these, Caridina tetrazonasp. nov. is described and illustrated as new to science. It can be easily distinguished from its congeners based on a combination of characters, which includes a short rostrum, the shape of the endopod of the male first pleopod, the segmental ratios of antennular peduncle and third maxilliped, the slender scaphocerite, and the absence of a median projection on the posterior margin. Live individuals of the new species display a unique coloration pattern with four dark blue transverse bands on the body, and can be easily recognized in the field. So far, despite considerable surveying efforts made on neighboring islands, this species has only been found from a small stream on Dawanshan Island, which suggests that it may have a very limited range, probably endemic to Dawanshan Island. Molecular characteristics of the mitochondrial cytochrome c oxidase subunit I (COI) demonstrate that this species shows sufficient interspecific divergence from its congeners, including C. serrata Stimpson, 1860, which was found in four streams on Dawanshan Island, and has been previously reported on the neighboring islands of Hong Kong, Dong’ao, Wailingding, and Guishan.

Diversity of freshwater shrimp (decapoda) from bandealit rivers meru betiri national park, East Java, Indonesia

Freshwater ecosystems are habitat for macroinvertebrate, fish and reptile groups. One of the macroinvertebrates that can be found in freshwater habitat is shrimp which belongs to the class of Crustaceae, order of Decapoda. This study aims to determine diversity and the abiotic conditions of freshwater shrimp habitat. Determination of sampling locations was done by purposive sampling based on the habitat type of freshwater shrimp and followed by road sampling that takes the straight path from the designated sampling location. The tools used to catch freshwater shrimp are traps and tray nett. The results obtained in the Bandealit river of Meru Betiri National Park were five species of freshwater shrimp consisting of 2 families. The diversity index of freshwater shrimp in the Bandealit river was classified as moderate by the analysis of diversity index. Meru Betiri National Park has ideal abiotic conditions for freshwater shrimp life.

Habitat segregation among freshwater shrimp species in an Amazonian rainforest stream system

Abstract Resource partitioning is a stabilising mechanism known to maintain species diversity in a variety of environments. Assemblages of stream shrimp species are structured by habitat features and predation. Therefore, segregation along habitat dimensions could facilitate coexistence among species in shrimp assemblages even when segregation is a result of predation pressure by fish species. These ecological interactions take place on a background modulated by biogeographic features, such as connectivity among drainages. However, these generalisations are mainly based on studies undertaken in temperate regions. We investigated whether abundances of rainforest shrimp species are related to habitat dimensions, and whether habitat–abundance relationships might be mediated through fish‐assemblage structure and the effect of drainages on connectivity. We detected effects of habitat variation on densities of shrimp species, but the magnitudes of the effects were larger for some species than others. Fish‐assemblage composition also affected shrimp densities. Two of the three species of shrimp showed some degree of habitat specialisation, but only along current‐velocity, depth, and pH gradients. Habitat segregation among species occurred along the current‐velocity and pH gradients. Relationships between density and environmental gradients differed between catchments for only one species and only along the pH gradient. Our findings provide evidence that rainforest‐stream shrimp species respond differently to environmental gradients and this could facilitate coexistence among species. However, interactions with fish seem to have a stronger effect on species densities, and consequently species segregation, than direct effects of the environmental gradients, resulting in apparent competition for these resources.

Estimates of growth and longevity of six species of freshwater shrimps (Macrobrachium spp.) (Decapoda: Caridea: Palaemonidae) from Costa Rica

AbstractInformation about growth is of particular relevance for stock assessment and management as well as for evaluating the aquaculture potential of any decapod species, but this information is lacking for the Central American species of MacrobrachiumSpence Bate, 1868. We collected specimens of six species of Macrobrachium monthly (February 2006 to August 2008) along the Pacific slope of Costa Rica. The collected individuals were sexed and weighted, and total length (TL) and carapace length (CL) were measured. The von Bertalanffy growth model was fitted to the data by applying the maximum likelihood method. The species analyzed reaching theoretically the largest sizes were M. americanum (Spence Bate, 1868), M. tenellum (Smith, 1871), and M. panamenseRathbun, 1912. With few exceptions, maximum sizes of all species were generally higher than those published in previous reports, suggesting that environmental conditions are favorable and anthropogenic impacts may be less severe in Costa Rica than in other countries. Only M. americanum exceeded the asymptotic total length estimates of other species, corroborating that this species is considered as one of the largest congeners worldwide. Estimated maximum age ranged from 3.9 (M. occidentaleHolthuis, 1950) to 11.5 yrs (M. tenellum). All six Macrobrachium species showed a positive allometric growth type. The model describing the length-weight relationship was statistically significant (P < 0.05) for all species. Although the maximum likelihood method has been applied so far mainly to compare different growth models, here we used this method to generate the first growth estimates for the six species from Costa Rica, and future studies might use this method to compare growth patterns among different species.

Exploring community assembly among Javanese and Balinese freshwater shrimps (Atyidae, Palaemonidae) through DNA barcodes

Species proliferate through evolutionary mechanisms but coexist through ecological dynamics. As such, it might be expected that mechanisms of speciation and species maintenance jointly influence the settlement of ecological communities, a process called community assembly. Disentangling the relative contribution of evolutionary and ecological dynamics might be a difficult task, particularly so for the tropical biotas due to their extreme diversity and large knowledge gaps. Here, we explore genetic diversity and distribution of 23 freshwater shrimp species of the genera Caridina and Macrobrachium in Sundaland to examine patterns of species co-occurrence based on 1583 observations across 19 sites in Java and Bali islands. DNA-based species delimitation methods applied to 204 cytochrome oxidase I sequences detected 30 operational taxonomic units and a few cases of deep intraspecific divergence. Species co-occurrence and phylogenetic community structure show no departure from expectations under a random distribution of species in landscapes and support a lottery model of community assembly. Species age estimates expand beyond the geological settlement of Sundaland, suggesting that species proliferation and community assembly are driven by mechanisms acting at distinct spatial and temporal scales.

Komposisi Jenis Udang Air Tawar di Sungai Batambean, Pulau Labobo, Banggai Laut, Sulawesi Tengah, Indonesia

Labobo isle is one of the satellite isle located around the mainland of Sulawesi Island. This study aims to determine the species composition of freshwater shrimp in the Batambean Stream located on Labobo Island, Banggai Laut, Central Sulawesi, Indonesia. A purposive sampling method based on the habitat of freshwater shrimps was applied to collect the shrimps. Measurement of abiotic environmental factors is carried out before samples collection. Furthermore, freshwater shrimp are collected using tray net and hand net. Collected specimens were preserved in alcohol 96%. The specimen wasidentified at the Laboratory of Animal Biosystematics and Evolution, Department of Biology, Faculty of Sciences, Tadulako University. The composition of freshwater shrimp species in the Batambean Stream consists of four species, namely Macrobrachium equidens, M. australe, and M. latidactylus and Caridina gracilipes. The first three species belong to the family Palaemonidae while the latter species is a member of the family Atyidae. The brief description and conservation status of each species were also provided

Molecular identification and expression profiles of four splice variants of Sex-lethal gene in Cherax quadricarinatus.

Cherax quadricarinatus, as one of the world's most valuable freshwater shrimp species, has received extensive attention in recent years. As males grow larger and faster than females, development of the sex control breeding techniques is of great interest, but knowledge on sex determination and differentiation in C. quadricarinatus remains poorly unknown. Sxl (Sex-lethal) is an important gene in the sexual differentiation regulatory hierarchy. It reflects the ratio of sex chromosomes to autosomes into molecule changes and directs sex-specific splicing forms of precursor mRNA. In the present study, the full-length cDNA sequences of four Sxl splice variants were identified from C. quadricarinatus, designated as CqSxl1, CqSxl2, CqSxl3 and CqSxl4, respectively. Sequence analysis determined different splicing sites near the translation termination region of four Sxl transcript isoforms. Two highly conserved classical RRM domains were found according to predicted secondary structures of Sxl proteins. mRNA expression of CqSxl in different tissues, developmental stage of embryos and testes were investigated by real-time quantitative PCR. Among four isoforms, CqSxl3 showed tissue specificity with higher expression levels in testis than in ovary. CqSxl1 and CqSxl4 were found widely expressed in various tissues and CqSxl2 was almost undetectable. In early developmental stages, the expression levels of CqSxl1/3/4 gradually increased along with embyonic development. In addition, CqSxl genes presented the higher transcript levels in the early stage of testis development. Furthermore, CqSxl3 silencing induced a significant decrease of the transcript of Cq-IAG, an androgenic hormone-encoding gene responsible for masculine development. These data indicate that CqSxl3 might be involved in male sex determination in C. quadricarinatus. Our study will contribute to understanding the mechanism of sex determination in C. quadricarinatus, and also can provide theoretical guidance for establishing a sex control technology.

A new freshwater shrimp species of the genus Palaemon Weber, 1795 (Decapoda: Caridea: Palaemonidae) from northeastern Japan.

The palaemonid shrimp genus Palaemon Weber 1795 is currently represented by 87 species worldwide, of which 36 species inhabit freshwater environments. In this study, we describe a new species of the genus, P. septemtrionalis, primarily based on material collected from rivers in Miyagi Prefecture, Tohoku District, northeastern Japan. The present new species is morphologically and genetically close to Palaemon paucidens De Haan, 1841, but it is morphologically distinguishable from the latter by the chela of the pereopod 2 being longer than the carpus (versus shorter than the carpus in P. paucidens) and the possession of a low, laminar convexity on the flexor margin of the pereopod 3 dactylus just proximal to the base of the unguis (such a laminar structure is absent in P. paucidens). Comparison of partial sequences of the mitochondrial 16S rRNA gene supports the recognition of the new species. Examination of museum collections and a BLAST search on GenBank revealed that the geographical range of the new species includes the Sea of Japan side ranging from Hokkaido to Hyogo Prefecture and the Pacific side ranging from Aomori to Miyagi Prefecture. An identification key to the 13 Japanese species of the genus is presented.

Reproductive characteristics of the freshwater shrimp, Macrobrachium macrobrachion (Herklots, 1851) in the water bodies of Benin, West Africa

Abstract The palaemonid shrimp Macrobrachium macrobrachion is widely distributed in coastal rivers, estuaries and inland waters of West Africa. This species is economically important because it is the one of the two main freshwater shrimp commercially exploited by artisanal fisheries in southern Benin, besides showing great potential for aquaculture. Despite this, little is known about its reproductive biology in the natural environment. Considering these facts, the present study aimed to establish some breeding parameters for M. macrobrachion in Benin. Overall, 2424 specimens were collected between May 2015 and October 2016. Monthly changes in gonado-somatic index (GSI) and hepato-somatic index (HSI) suggest that the breeding season runs from July to October. In the Ouémé River Delta, the estimated size at first maturity is 8.16 cm TL in females, while it is 7.47 cm TL in males. In the Mono River/Grand-Popo Lagoon complex, the size at first maturity is 7.27 cm TL in females while it is 6.56 cm TL in males. The structure of the ovary as observed in females from either site just before spawning, shows the presence of two types of oocytes at different sizes and various developmental stages. Analysis of such ovarian structure suggests that M. macrobrachion has a synchronous oogenesis with a breeding season limited to a few months of the year. Fecundity was found to be between 3144 and 26 489 eggs in the Ouémé Delta, while it goes from 3124 to 22 660 eggs in the Mono River/Grand-Popo Lagoon complex. The present study provides important information on the reproductive biology of M. macrobrachion and of freshwater shrimp in general, and can also serve as a significant foundation for the aquaculture of species of freshwater shrimp.

Neocaridinafonticulata, a new land-locked freshwater shrimp from Hengchun Peninsula, Taiwan (Decapoda, Caridea, Atyidae).

A new species of land-locked freshwater shrimp, Neocaridinafonticulatasp. n. (Atyidae), is described from Kenting, Hengchun Peninsula, Pingtung County, southern Taiwan. This new species can be distinguished from its congeners by rostrum structure, pereiopods, and male first and second pleopods. The molecular evidence of mitochondrial cytochrome oxidase subunit I (COI) also supports the establishment of a new species. This is the third endemic species of Neocaridina known from Taiwan.

Procambarus clarkii (Girard, 1852) and crayfish plague as new threats for biodiversity in Indonesia

Abstract Numerous freshwater crayfish species are known to become successful invaders when introduced to new territories. One of the most invasive species in this group is the red swamp crayfish, Procambarus clarkii (Girard, 1852). In addition to other characteristics facilitating its invasiveness, it is also a vector of crayfish plague, a disease mostly lethal to crayfish of non‐North American origin. Procambarus clarkii, at present the most widespread crayfish species globally, is popular in many countries both for human consumption and as an ornamental animal. An established population of this species was documented for the first time within Indonesia, representing the first record for maritime Southeast Asia. The species is also common in the local ornamental pet trade. Infection by the crayfish plague pathogen Aphanomyces astaci Schikora was confirmed both in the outdoor population of P. clarkii and in one of the surveyed pet shops. Furthermore, A. astaci was detected in specimens of freshwater crab and shrimp species coexisting with P. clarkii. Local climatic conditions and the species temperature requirements suggest a high probability of the establishment of P. clarkii in Indonesia. Its further spread could irreversibly damage populations of many native endemic crustaceans in the country (as well as elsewhere in the region), and the thriving local aquacultures of the redclaw crayfish Cherax quadricarinatus (von Martens, 1868) may also be threatened. The total ban of P. clarkii and other crayfish species of North American origin in Indonesia is strongly recommended, especially considering that aquaculture and trade with Australasian species is a viable alternative option.

Spatial distributions and environmental relationships of two species complexes of freshwater atyid shrimps

AbstractKnowledge of cryptic species distributions and their relationships with environmental factors may be extremely valuable for biodiversity conservation. In freshwater ecosystems, morphologically cryptic species often have different geographic distributions that can overlap to varying extents. The importance of differential species responses to environmental conditions in determining their spatial distributions is, however, unclear. Here, we evaluated the importance of species responses to environmental drivers, in particular the physicochemical factors, in the spatial distributions and environmental relationships of two shrimp species complexes Caridina indistincta Calman, 1926 and Paratya australiensis Kemp, 1917. We analyzed shrimp specimens from 89 sites in 17 catchments across South‐East Queensland by sequencing a fragment of the mitochondrial cytochrome c oxidase subunit I gene (COI) to identify individuals. Furthermore, although there is evidence that morphologically the cryptic species of these shrimps differ very little, we made detailed morphological assessments to combine with molecular data, hoping to be able to distinguish among the species more easily and cheaply for future studies. There were significant morphological differences among the three cryptic species of the C. indistincta species complex, specifically in carapace length (cl), number of dorsal teeth (nDt), number of ventral teeth (nVt), teeth posterior to orbital margin (TPOM), and the calculated ratios A/rl, and rl/cl, while the two lineages of the P. australiensis species complex differed in the number of dorsal teeth (nDt) and the calculated ratios of A/rl, rl/cl, and rh/ch. To determine the importance of species responses in explaining the spatial distribution of cryptic species based on the species‐variables relationships, a redundancy analysis (RDA) was used to summarize these relationships. This ordination analysis showed distinct differences among cryptic species in their correlation with water quality variables and elevation. C. indistincta sp. B and C. indistincta sp. D were significantly associated with elevation and dissolved oxygen range, respectively. As well, P. australiensis lineages 4 and 6 were significantly correlated with elevation and conductivity, respectively. Overall, our results demonstrated the advantage of using analyses of biotic and abiotic variables as a valid approach for defining species responses to abiotic factors in cryptic species of atyid freshwater shrimps.

Freshwater prawns of the genus Macrobrachium (Decapoda: Palaemonidae) from the San Pedro Mezquital River, Nayarit, Mexico

The San Pedro-Mezquital River basin in Nayarit, Mexico has the majority of freshwater prawns of the genus Macrobrachium reported for the Mexican Pacific coast. Six species of freshwater shrimp are reported Macrobrachium americanum , M. occidentale , M. digueti , M. michoacanus , M. hobbsi and M. tenellum . The higher richness and diversity of freshwater prawns are found on the coastal plain. The presence of prawns in relation to the altitudinal gradient is discussed.

Jenis-jenis udang air tawar dan karakteristik habitat di tujuh sungai Kabupaten Aceh Barat Provinsi Aceh

This study aims to determine the species of freshwater shrimp and habitat character in District West Aceh. The research conducted in April - July 2014, include at seven observation site, Used purposive sampling methode. At each station, samples were collected for 30-45 minutes with a length of 3-5 m sampling area along the river in a direction against the current. Samples were taken to the Basic Biology Laboratory of STKIP Bina Bangsa Meulaboh, for further identification. The identification of shrimp based on morphological features, taxonomic characteristics and body measurements. Shrimp habitats in each site are described and documented. There are five species of freshwater shrimp found in West Aceh, ie: Macrobrachium rosenbergii, M.empulipke, M. equidens, M. australe, and M. lanchesteri. There are different species of Freshwater shrimp found in different habitat characters.

Freshwater shrimps (Macrobrachium depressimanum and Macrobrachium jelskii) as biomonitors of Hg availability in the Madeira River Basin, Western Amazon.

Total mercury (THg) concentrations measured in two freshwater shrimp species (Macrobrachium depressimanum and Macrobrachium jelskii) showed a relationship with the location of artisanal and small-scale gold mining (ASGM) from the Madeira River Basin, Western Amazon. Between August 2009 and May 2010, 212 shrimp samples were collected in the confluence of the Madeira River with three of its tributaries (Western Amazon). THg concentration was quantified in the exoskeleton, hepatopancreas and muscle tissue of the shrimps by cold vapor atomic absorption spectrophotometry. There were no significant differences between the two shrimp species when samples came from the Madeira River, but Hg concentrations were significantly lower in a tributary outside the influence of the gold mining area. Average THg concentrations were higher in the hepatopancreas (up to 160.0ngg-1) and lower in the exoskeleton and muscle tissue (10.0-35.0ngg-1 and < 0.9-42.0ngg-1, respectively). Freshwater shrimps from the Madeira River respond to local environmental levels of Hg and can be considered as biomonitors for environmental Hg at this spatial scale. These organisms are important for moving Hg up food webs including those that harbor economic significant fish species and thus enhancing human exposure.

Integrative taxonomy helps separate four species of freshwater shrimps commonly overlooked as Caridina longirostris (Crustacea : Decapoda : Atyidae) on Indo-West Pacific islands

Caridina longirostris H. Milne Edwards, 1837 described from specimens supposedly from La Macta River near Oran, Algeria, is an emblematic species of the ‘C. nilotica complex’. Until now this species was thought to have a wide distribution in the Indo-Pacific region. Recently, numerous specimens identified as C. longirostris were collected from various Indo-West Pacific localities. In the context of integrative taxonomy, both old and newly collected specimens were morphologically and genetically studied. Four species allied to C. longirostris are here identified: C. appendiculata Jalihal &amp;amp; Shenoy, 1998, C. brevidactyla Roux, 1920, C. gracilipes De Man, 1892 and C. meridionalis Roux, 1926. Detailed re-descriptions of these four species are given as well as their geographical and ecological distributions. Caridina nilotica var. brevidactyla is revalidated as the species C. brevidactyla, and C. coulaborensis Richard &amp;amp; Clark, 2014, C. fritzi Richard &amp;amp; Clark, 2014 and C. solamulieres Richard &amp;amp; Clark, 2014 are considered junior synonyms of C. meridionalis. The position of these species in the troublesome ‘C. nilotica complex’ is clarified and some species are synonymised. A key is provided to facilitate identification.