Research Article |
Corresponding author: Eliana Zelada-Mázmela ( ezelada@uns.edu.pe ) Academic editor: Luis Ernesto Bezerra
© 2025 Eliana Zelada-Mázmela, Lorenzo E. Reyes-Flores, Luis De Stefano-Beltrán.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Zelada-Mázmela E, Reyes-Flores LE, De Stefano-Beltrán L (2025) Phylogeny of Macrobrachium spp. (Decapoda, Pleocyemata) from Peru based on mitochondrial and nuclear data reveals a species complex comprising M. digueti (Bouvier, 1895) and M. transandicum Holthuis, 1950. ZooKeys 1224: 1-28. https://doi.org/10.3897/zookeys.1224.130537
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Prawns of the genus Macrobrachium represent a highly diverse group of high commercial value worldwide. Eight Macrobrachium species have been reported from the Peruvian Pacific slope, but their phylogenetic relationships are still unknown. To investigate the systematics of Macrobrachium species from Peru, morphological identification and molecular data from nucleotide sequences of three genes were used: cytochrome c oxidase subunit I, 16S rRNA, and 28S rRNA. Based on morphological taxonomy, six species were successfully identified: M. americanum, M. digueti, M. gallus, M. inca, M. panamense, and M. transandicum. However, the phylogenetic inference results supported the species validity of only the first five species; all prawn individuals that were morphologically identified as M. transandicum were recovered within the M. digueti group, showing interspecific genetic distances near zero, suggesting that both species belong to the same species-level lineage, which may represent in the “olfersii species complex”. Our analyses also corroborated the genetic proximity of sibling species M. inca–M. americanum and M. gallus–M. panamense, and the monophyletic origin of Macrobrachium species from Peruvian populations. This study represents the first comprehensive phylogenetic analyses of Macrobrachium species from Peru, and contributes the first publicly available DNA sequences for M. inca and M. gallus, as well as the first sequences of M. americanum, M. panamense, M. digueti, and M. transandicum collected from Peruvian rivers.
Genetic variability, Macrobrachium, molecular phylogenetics, olfersii species complex, Peruvian river prawns, systematics
Prawns of the genus Macrobrachium Spence Bate, 1868 are cosmopolitan species inhabiting freshwater and estuarine ecosystems (
More recently, this group has received special attention with studies mainly related to taxonomy and molecular systematics (
In Peru, eight Macrobrachium species (M. gallus, M. inca, M. transandicum, M. americanum Bate, 1868, M. tenellum (Smith, 1871), M. digueti (Bouvier, 1895), M. hancocki Holthuis, 1950, and M. panamense Rathbun, 1912) have been reported to occur on the Pacific slope (
Currently, there is no established Macrobrachium prawn fishery in Peru, and as with other Macrobrachium species, as it is generally a complementary and artisanal activity associated with the rainy season. The organisms caught are consumed locally or marketed in places close to the fishing grounds. However, their widespread use means that fishing pressure is increasing and the availability of areas for natural production is decreasing, aggravated by pollution, which limits the potential of natural populations. (
Prawns are key elements of the food chain from freshwater environments, playing a major role not only as omnivorous scavengers and detritus feeders, but also as prey for fish, birds, and reptiles. Furthermore, they are considered important ecosystem engineers (
A total of 136 specimens belonging to the genus Macrobrachium were collected between December 2012 and February 2016 in rivers and estuaries from six Peruvian coastal regions including Tumbes, Piura, Lambayeque, La Libertad, Ancash, and Lima (Fig.
Geographic map of Peru showing sampling locations of Macrobrachium species (adapted from https://www.naturalearthdata.com/downloads/10m-raster-data/10m-shaded-relief/).
Total genomic DNA was extracted from the muscle tissue of the pleopods, using the commercial GeneJET Genomic DNA Purification Kit (Thermo Fisher Scientific, Carlsbad, CA, USA). DNA quantification was calculated using an Epoch spectrophotometer (BioTek Instruments, Winooski, VT, USA). Extracted DNA quality was assessed by the 260/280 ratio and its integrity was observed by 1% agarose gel electrophoresis using GelRed Nucleic Acid Gel Stain as a DNA intercalator. Oligonucleotide sequences used for the polymerase chain reaction (PCR) amplification of partial fragments of COI, 16S rRNA, and 28S rRNA genes are shown in Table
Primer sequences used to amplify mitochondrial (COI and 16S rRNA) and nuclear (28S rRNA) genes.
Primer name | Direction | Sequence (5’ -- 3’) | Gene | Reference |
---|---|---|---|---|
Col6bF | Forward | ACAAATCATAAAGATATYGG | COI | Schubart and Heber (2006) |
COH6R | Reverse | TADACTTCDGGRTGDCCAAARAAYCA | ||
1471 | Forward | CCTGTTTANCAAAAACAT | 16S rRNA |
|
1472 | Reverse | AGATAGAAACCAACCTGG | ||
28RDDF D2CFD45F | Forward | TACCGTGAGGGAAAGTTGAAA | 28S rRNA |
|
28D2CRD45R | Reverse | AGACTCCTTGGTCCGTGTTT |
A matrix containing multi-aligned sequences was constructed for each gene analyzed gene (COI, 16S rRNA, and 28S rRNA) using all the obtained sequences from M. americanum, M. digueti, M. panamense, and M. transandicum. In each matrix, we included sequences from three specimens of M. gallus and M. inca collected from each river of our field surveys, avoiding common or shared haplotypes. Palaemon hancocki was used as an outgroup. All DNA sequences obtained in this study have been deposited in GenBank/EMBL/DDBJ databases with accession numbers from OR941326–OR941602 (Suppl. material
Three different phylogenetic methods were performed for each of the three selected genes including maximum parsimony (MP), maximum likelihood (ML) and Bayesian inference (BI), implemented in PAUP v. 4.0 (
Among the 136 collected specimens, a total of six Macrobrachium species (Suppl. material
Overall, the results of phylogeny estimation approaches (MP, ML and BI) inferred with single and concatenated gene datasets showed similar topologies, branch lengths, and high bootstrap support and posterior probabilities. All approaches (MP, ML, and BI) (Figs
Phylogenetic tree based on maximum parsimony generated using 83 partial sequences of the mitochondrial COI gene from six Macrobrachium species collected in Peruvian rivers of the Pacific slope. Bootstrap values ≥ 50% are shown. P. hancocki was used as outgroup. GenBank accession numbers OR941326–OR941408. Abbreviations: Mt: M. transandicum; Mp: M. panamense; Mi: M. inca; Mg: M. gallus; Ma: M. americanum; Md: M. digueti, Ph: P. hancocki; Chir: Chira River; Tb: Tumbes River; Zr, Zar: Zarumilla River; Vir: Virú River; Pat: Pativilca River; JR: Juana Ríos River; Chao: Chao River; Lcr: Lacramarca River; Hb: Nepeña River; For: Fortaleza River; San: Santa River; Moch: Moche River; Chic: Chicama River; Sup: Supe River; Zn: Zaña River.
Phylogenetic tree based on maximum likelihood inference generated under the GTRGAMMA substitution model using 83 partial sequences of the mitochondrial COI gene from six Macrobrachium species collected in Peruvian rivers of the Pacific slope. Bootstrap values ≥ 50% are shown. P. hancocki was used as outgroup. GenBank accession numbers OR941326–OR941408. Abbreviations: Mt: M. transandicum; Mp: M. panamense; Mi: M. inca; Mg: M. gallus; Ma: M. americanum; Md: M. digueti; Ph: P. hancocki; Chir: Chira River; Tb: Tumbes River; Zr, Zar: Zarumilla River; Vir: Virú River; Pat: Pativilca River; JR: Juana Ríos River; Chao: Chao River; Lcr: Lacramarca River; Hb: Nepeña River; For: Fortaleza River; San: Santa River; Moch: Moche River; Chic: Chicama River; Sup: Supe River; Zn: Zaña River.
Phylogenetic tree based on Bayesian Inference approach generated under the GTR+I+G substitution model using 83 partial sequences of the mitochondrial COI gene from six Macrobrachium species collected in Peruvian rivers of the Pacific slope. Bootstrap values ≥ 50% are shown. P. hancocki was used as outgroup. GenBank accession numbers OR941326–OR941408. Abbreviations: Mt: M. transandicum; Mp: M. panamense; Mi: M. inca; Mg: M. gallus; Ma: M. americanum; Md: M. digueti; Ph: P. hancocki; Chir: Chira River; Tb: Tumbes River; Zr, Zar: Zarumilla River; Vir: Virú River; Pat: Pativilca River; JR: Juana Ríos River; Chao: Chao River; Lcr: Lacramarca River; Hb: Nepeña River; For: Fortaleza River; San: Santa River; Moch: Moche River; Chic: Chicama River; Sup: Supe River; Zn: Zaña River.
Intraspecific genetic distances based on a partial fragment of the COI gene. Analyses were conducted using the Kimura 2-parameter model (K2P) with 1000 bootstrap replicates.
Species | Genetic distance (d) | Standard error (SE) |
---|---|---|
M. inca | 0.007875916 | 0.001348432 |
M. gallus | 0.016703893 | 0.002978309 |
M. panamense | 0.009035682 | 0.002716602 |
M. transandicum | 0.004338227 | 0.0015591 |
M. digueti | 0.006141983 | 0.001761096 |
M. americanum | 0.017789742 | 0.003291708 |
P. hancocki | 0.003437498 | 0.001656147 |
Interspecific genetic distances (below diagonal) based on a partial fragment of the COI gene. Analyses were conducted using the Kimura 2-parameter model (K2P) with 1000 bootstrap replicates. Standard error estimates are shown above the diagonal.
Species | M. inca | M. americanum | M. digueti | M. panamense | M. transandicum | M. gallus | P. hancocki |
---|---|---|---|---|---|---|---|
M. inca | – | 0.017348 | 0.020433 | 0.021025 | 0.020447 | 0.019419 | 0.022040 |
M. americanum | 0.179606 | – | 0.018468 | 0.017899 | 0.018470 | 0.018310 | 0.021414 |
M. digueti | 0.238992 | 0.188721 | – | 0.019072 | 0.001463 | 0.017165 | 0.019316 |
M. panamense | 0.228502 | 0.186465 | 0.203847 | – | 0.019046 | 0.021432 | 0.021106 |
M. transandicum | 0.237390 | 0.188609 | 0.005268 | 0.202176 | – | 0.017119 | 0.019351 |
M. gallus | 0.213766 | 0.198608 | 0.189913 | 0.236212 | 0.187403 | – | 0.021735 |
P. hancocki | 0.262074 | 0.238108 | 0.211475 | 0.241439 | 0.210927 | 0.253760 | – |
16S rRNA gene phylogenetic trees based in MP (Fig.
Phylogenetic tree based on Maximum Parsimony approach generated using 93 partial sequences of the mitochondrial 16S rRNA gene from six Macrobrachium species collected in Peruvian rivers of the Pacific slope. Bootstrap values ≥ 50% are shown. P. hancocki was used as outgroup. GenBank accession numbers OR941603–OR941697. Abbreviations: Mt: M. transandicum; Mp: M. panamense; Mi: M. inca; Mg: M. gallus; Ma: M. americanum; Md: M. digueti; Ph: P. hancocki; Chir: Chira River; Tb: Tumbes River; Zr, Zar: Zarumilla River; Vir: Virú River; Pat: Pativilca River; JR: Juana Ríos River; Chao: Chao River; Lcr: Lacramarca River; Hb: Nepeña River; For: Fortaleza River; San: Santa River; Moch: Moche River; Chic: Chicama River; Sup: Supe River; Zn: Zaña River.
Phylogenetic tree based on maximum likelihood inference generated under the GTRGAMMA substitution model using 93 partial sequences of the mitochondrial 16S rRNA gene from six Macrobrachium species collected in Peruvian rivers of the Pacific slope. Bootstrap values ≥ 50% are shown. P. hancocki was used as outgroup. GenBank accession numbers OR941603–OR941697. Abbreviations: Mt: M. transandicum; Mp: M. panamense; Mi: M. inca; Mg: M. gallus; Ma: M. americanum; Md: M. digueti; Ph: P. hancocki; Chir: Chira River; Tb: Tumbes River; Zr, Zar: Zarumilla River; Vir: Virú River; Pat: Pativilca River; JR: Juana Ríos River; Chao: Chao River; Lcr: Lacramarca River; Hb: Nepeña River; For: Fortaleza River; San: Santa River; Moch: Moche River; Chic: Chicama River; Sup: Supe River; Zn: Zaña River.
Phylogenetic tree based on Bayesian Inference approach generated under the K80+I+G substitution model using 93 partial sequences of the mitochondrial 16S rRNA gene from six Macrobrachium species collected in Peruvian rivers of the Pacific slope. Bootstrap values and posterior probabilities ≥ 50% are shown. P. hancocki was used as outgroup. GenBank accession numbers OR941603–OR941697. Abbreviations: Mt: M. transandicum; Mp: M. panamense; Mi: M. inca; Mg: M. gallus; Ma: M. americanum; Md: M. digueti; Ph: P. hancocki; Chir: Chira River; Tb: Tumbes River; Zr, Zar: Zarumilla River; Vir: Virú River; Pat: Pativilca River; JR: Juana Ríos River; Chao: Chao River; Lcr: Lacramarca River; Hb: Nepeña River; For: Fortaleza River; San: Santa River; Moch: Moche River; Chic: Chicama River; Sup: Supe River; Zn: Zaña River.
Intraspecific genetic distances based on a partial fragment of the 16S rRNA gene. Analyses were conducted using the Kimura 2-parameter model (K2P) with 1000 bootstrap replicates.
Species | Genetic distance (d) | Standard error (SE) |
---|---|---|
M. inca | 0.005080317 | 0.001149334 |
M. americanum | 0.001143241 | 0.00077876 |
M. digueti | 0.002001609 | 0.001112749 |
M. panamense | 0.004003013 | 0.002731773 |
M. transandicum | 0.001942077 | 0.000888224 |
M. gallus | 0.007245067 | 0.002351216 |
P. hancocki | 0.002803217 | 0.001658205 |
Interspecific genetic distances (below diagonal) based on a partial fragment of the 16S rRNA gene. Analyses were conducted using the Kimura 2-parameter model (K2P) with 1000 bootstrap replicates. Standard error estimates are shown above the diagonal.
Species | M. inca | M. americanum | M. digueti | M. panamense | M. transandicum | M. gallus | P. hancocki |
---|---|---|---|---|---|---|---|
M. inca | – | 0.014232 | 0.012861 | 0.001992 | 0.012809 | 0.014017 | 0.023743 |
M. americanum | 0.098973 | – | 0.014303 | 0.014626 | 0.014328 | 0.013072 | 0.023497 |
M. digueti | 0.077575 | 0.095831 | – | 0.013265 | 0.000785 | 0.015049 | 0.023423 |
M. panamense | 0.005348 | 0.101574 | 0.079840 | – | 0.013213 | 0.014356 | 0.024126 |
M. transandicum | 0.077179 | 0.096172 | 0.001891 | 0.079458 | – | 0.015013 | 0.023423 |
M. gallus | 0.102915 | 0.092403 | 0.117623 | 0.104548 | 0.117217 | – | 0.024178 |
P. hancocki | 0.209718 | 0.207972 | 0.216827 | 0.213408 | 0.216353 | 0.229778 | – |
The results from phylogenetic approaches (MP, Fig.
Phylogenetic tree based on Maximum Parsimony approach generated using 28 partial sequences of the nuclear 28S rRNA gene from six Macrobrachium species collected in Peruvian rivers of the Pacific slope. Bootstrap values ≥ 50% are shown. P. hancocki was used as outgroup. GenBank accession numbers OR941575–OR9411602. Abbreviations: Mt: M. transandicum; Mp: M. panamense; Mi: M. inca; Mg: M. gallus; Ma: M. americanum; Md: M. digueti; Ph: P. hancocki; Chir: Chira River; Tb: Tumbes River; Zr, Zar: Zarumilla River; Vir: Virú River; Pat: Pativilca River; JR: Juana Ríos River; Chao: Chao River; Lcr: Lacramarca River; Hb: Nepeña River; For: Fortaleza River; San: Santa River; Moch: Moche River; Chic: Chicama River; Sup: Supe River; Zn: Zaña River.
Phylogenetic tree based on maximum likelihood inference generated under the GTRGAMMA substitution model using 28 partial sequences of the nuclear 28S rRNA gene from six Macrobrachium species collected in Peruvian rivers of the Pacific slope. Bootstrap values ≥ 50% are shown. P. hancocki was used as outgroup. GenBank accession numbers OR941575–OR9411602. Abbreviations: Mt: M. transandicum; Mp: M. panamense; Mi: M. inca; Mg: M. gallus; Ma: M. americanum; Md: M. digueti; Ph: P. hancocki; Chir: Chira River; Tb: Tumbes River; Zr, Zar: Zarumilla River; Vir: Virú River; Pat: Pativilca River; JR: Juana Ríos River; Chao: Chao River; Lcr: Lacramarca River; Hb: Nepeña River; For: Fortaleza River; San: Santa River; Moch: Moche River; Chic: Chicama River; Sup: Supe River; Zn: Zaña River.
Phylogenetic tree based on Bayesian Inference approach generated under the GTR+I substitution model using 28 partial sequences of the nuclear 28S rRNA gene from six Macrobrachium species collected in Peruvian rivers of the Pacific slope. Bootstrap values and posterior probabilities ≥ 50% are shown. PP. hancocki was used as outgroup. GenBank accession numbers OR941575–OR9411602. Abbreviations: Mt: M. transandicum; Mp: M. panamense; Mi: M. inca; Mg: M. gallus; Ma: M. americanum; Md: M. digueti; Ph: P. hancocki; Chir: Chira River; Tb: Tumbes River; Zr, Zar: Zarumilla River; Vir: Virú River; Pat: Pativilca River; JR: Juana Ríos River; Chao: Chao River; Lcr: Lacramarca River; Hb: Nepeña River; For: Fortaleza River; San: Santa River; Moch: Moche River; Chic: Chicama River; Sup: Supe River; Zn: Zaña River.
The topology in the phylogenetic trees was also similar: M. americanum and M. panamense were recovered in two discrete clades with high bootstrap support (100 and 98%) and posterior probabilities (100%). The results also showed that the BI phylogenetic tree grouped M. gallus with M. panamense and M. americanum with M. inca in sister clades with high nodal support (100% and 86%, respectively). The two former species have a long rostrum while the two latter species share a similar long and robust shape of the second pair of pereiopods. As shown in Table
Intraspecific genetic distances based on a partial fragment of the 28S rRNA. Analyses were conducted using the Kimura 2-parameter model (K2P) with 1000 bootstrap replicates.
Species | Genetic distance (d) | Standard error (SE) |
---|---|---|
M. americanum | 0.072173333 | 0.008788746 |
M. digueti | 0 | 0 |
M. transandicum | 0 | 0 |
M. gallus | 0 | 0 |
M. inca | 0 | 0 |
M. panamense | 0.021090406 | 0.004236636 |
P. hancocki | 0 | 0 |
Interspecific genetic distances (below diagonal) based on a partial fragment of the 28S rRNA. Analyses were conducted using the Kimura 2-parameter model (K2P) with 1000 bootstrap replicates. Standard error estimates are shown above the diagonal.
Species | M. americanum | M. digueti | M. transandicum | M. gallus | M. inca | M. panamense | P. hancocki |
---|---|---|---|---|---|---|---|
M. americanum | – | 0.018854 | 0.018854 | 0.019530 | 0.019097 | 0.019233 | 0.020815 |
M. digueti | 0.198629 | – | 0.000000 | 0.014078 | 0.013348 | 0.013639 | 0.016511 |
M. transandicum | 0.198629 | 0.000000 | – | 0.014078 | 0.013348 | 0.013639 | 0.016511 |
M. gallus | 0.213409 | 0.114759 | 0.114759 | – | 0.013662 | 0.010068 | 0.015985 |
M. inca | 0.199487 | 0.112660 | 0.112660 | 0.112873 | – | 0.013677 | 0.016695 |
M. panamense | 0.213907 | 0.117536 | 0.117536 | 0.077443 | 0.123234 | – | 0.014860 |
P. hancocki | 0.224814 | 0.143690 | 0.143690 | 0.135800 | 0.155865 | 0.129517 | – |
Overall, the phylogenetic results obtained by using the three concatenated datasets COI-16S rRNA, COI-28S rRNA, and 16S rRNA-28S rRNA (Suppl. material
The diversity of freshwater crustacean decapods from South America is represented by seven families including Palaemonidae. In Peru, twelve Palaemonidae species occur naturally, of which eight belong to the genus Macrobrachium (
Macrobrachium presents low phenotypic variability, so species classification is usually very complicated, creating many taxonomic difficulties within the genus (
During the morphological identification of M. transandicum we observed that both sexes displayed chelae of similar morphology (Suppl. material
To date, there is a lack of molecular studies of Macrobrachium species from Peru and most population study efforts have been focused on a single prawn species: C. (C.) caementarius, whose populations have been monitored periodically since 1996 by the Peruvian Marine Research Institute (IMARPE). Based on the reproductive periods determined for C. (C.) caementarius, a closed fishing season for all freshwater prawn species was established (
The present study represents the first effort to apply molecular data to analyze six of the eight different Macrobrachium species reported for Peru (
The geographic distribution of M. transandicum is not fully known and it has been reported that this species occurs only in three rivers in Colombia and one river in Peru (
The main objective of a molecular phylogenetics analysis is to infer the evolutionary history of a group of organisms and to output the results in a hierarchy branching diagram or phylogenetic tree (
The interspecific morphological conservation observed during the morphological identification of Macrobrachium is contrasted by the levels of genetic distances among species (
The addition of nuclear ribosomal genes for phylogeny studies of decapods has proven to be useful for different reasons including a lower evolutionary rate (
Robust phylogenetic inference is achieved by using good datasets that usually depend on many sequences of long lengths. In this regard, the use of concatenated gene datasets represents a potentially powerful approach. However, this method should be used only with genes that show consistent evolutionary patterns (
Herein, we were able to identify and successfully recover phylogenetic relationships of six out of the eight Macrobrachium species reported for the Peruvian Pacific slope: M. inca, M. gallus, M. transandicum, M. digueti, M. panamense, and M. americanum. Two species, M. tenellum and M. hancocki, were not found in our field surveys and therefore not included in our study]. Based on our molecular analyses of partial fragments of COI, 16S rRNA, and 28S rRNA genes, the validity of five of these six species is supported; all our phylogenetic analyses recovered prawns morphologically identified as M. transandicum within the same clade as M. digueti, showing interspecific genetic distances near zero, and suggesting that both species belong to the same species-level lineage. Therefore, we propose that M. transandicum should be included in the olfersii complex.
Among the three molecular markers used in this study, we found that COI followed by 28S rRNA demonstrated strong resolving power for species identification and phylogenetic inferences of Peruvian Macrobrachium species. The 28S rRNA gene was also useful in resolving the taxonomic status of M. panamense. The hypothesis that M. inca and M. gallus are related to M. americanum and M. panamense respectively, was supported only by the BI phylogenetic tree based on 28S rRNA, whose topology recovered M. inca and M. americanum (rostrum of medium size and second pair of pereiopods with unequal size) and M. gallus–M. panamense (long rostrum and thin and slender second pair of pereiopods) in sister clades; while the COI trees recovered only the clade, M. inca and M. americanum. Finally, the phylogenetic approaches used in this study (MP, ML, and BI) recovered similar topologies for all the analyzed genes (COI, 16S rRNA, 28S rRNA), supporting the monophyletic origin of Peruvian Macrobrachium species.
We express our gratitude to the National University of Santa, for allowing us to use the facilities of the Genetics, Physiology, and Reproduction Laboratory, as well as for providing most of reagents and supplies that were used in the present study, and to the anonymous reviewers for their valuable comments and suggestions.
The authors have declared that no competing interests exist.
No ethical statement was reported.
No funding was reported.
Conceptualization: LDSB, EVZM. Data curation: LERF. Formal analysis: EVZM. Funding acquisition: EVZM. Investigation: EVZM. Methodology: EVZM, LERF. Validation: LERF. Writing - original draft: EVZM. Writing - review and editing: LDSB.
Eliana Zelada-Mázmela https://orcid.org/0000-0002-5813-0954
Lorenzo E. Reyes-Flores https://orcid.org/0000-0002-1993-8010
Luis De Stefano-Beltrán https://orcid.org/0000-0002-5432-2916
All of the data that support the findings of this study are available in the main text or Supplementary Information.
Morphological identification of the six Macrobrachium species and Phylogenetic trees based on Bayesian inference
Data type: 7z
Explanation note: fig. S1. Macrobrachium transandicum Holthuis, 1950. A Female (collected from Zarumilla River) B Rostrum in close-up view. fig. S2. Macrobrachium transandicum Holthuis, 1950. Female (collected from Zarumilla River). A Major chela B Minor chela C Gonopore in coxae of the third pair of periopods. Note the width of the area around the fifth pair of periopods. fig. S3. Macrobrachium transandicum Holthuis, 1950. A Male (collected from Tumbes River) B Rostrum in close-up view C Major chela. fig. S4. Macrobrachium transandicum Holthuis, 1950. Male (collected from Tumbes River). A Minor chela B Gonopore, coxa fifth pair of periopods. Note the width of the area. fig. S5. Macrobrachium digueti (Bouvier, 1895). A Male (collected from Zarumilla River). B Rostrum in close-up view C Major chela. fig. S6. Macrobrachium panamense Rathbun, 1912. A Male (collected from Tumbes River) B Telson in close-up view C Rostrum close-up view. fig. S7. Macrobrachium gallus Holthuis, 1950. A Male (collected from Zarumilla River) B close-up view C Telson in close-up view. fig. S8. Macrobrachium americanum Spence Bate, 1950. A Male (collected from Zarumilla River) B Telson in close-up view. fig. S9. Macrobrachium inca Holthuis, 1950. A Male (collected from Chicama River) B Rostrum in close-up view C Rostrum close-up view of a female (collected from Santa River) D Telson in close-up view. fig. S10. Phylogenetic tree based on Bayesian inference approach generated under the GTR+I+G substitution model using concatenated dataset of the mitochondrial COI-16S rRNA genes from six Macrobrachium species collected in Peruvian rivers of the Pacific. Bootstrap values and posterior probabilities ≥ 50% are shown. P. hancocki was used as outgroup. Abbreviations: Mt: M. transandicum; Mp: M. panamense; Mi: M. inca; Mg: M. gallus; Ma: M. americanum; Md: M. digueti; Ph: P. hancocki. fig. S11. Phylogenetic tree based on Bayesian inference approach generated under the GTR+I+G substitution model using concatenated dataset of COI-28S rRNA genes from six Macrobrachium species collected in Peruvian rivers of the Pacific. Bootstrap values and posterior probabilities ≥ 50% are shown. P. hancocki was used as outgroup. Abbreviations: Mt: M. transandicum; Mp: M. panamense; Mi: M. inca; Mg: M. gallus; Ma: M. americanum; Md: M. digueti; Ph: P. hancocki. fig. S12. Phylogenetic tree based on Bayesian inference approach generated under the GTR+I+G substitution model using concatenated dataset of the 16S rRNA-28S rRNA genes from six Macrobrachium species collected in Peruvian rivers of the Pacific. Bootstrap values and posterior probabilities ≥ 50% are shown. P. hancocki was used as outgroup. Abbreviations: Mt: M. transandicum; Mp: M. panamense; Mi: M. inca; Mg: M. gallus; Ma: M. americanum; Md: M. digueti; Ph: P. hancocki.
Additional information
Data type: 7z
Explanation note: table S1. Coordinates of collection sites of Macrobrachium species in rivers of the Peruvian coast. table S2. Macrobrachium species identified in this study by morphological taxonomy 230 and molecular analyses. Sampling number (n), Peruvian rivers surveyed, and GenBank 231 accession numbers for each locus are shown. table S3. Key to species of Macrobrachium from Peru (