Remarks onMastigodiaptomus(Calanoida: Diaptomidae) from Mexico using integrative taxonomy, with a key of identification and three new species

Abstract

Background In Mexico, species of four families of free-living calanoid copepods have been recorded as inhabitants of several freshwater systems. These families are Centropagidae, Temoridae, Pseudodiaptomidae and Diaptomidae. The genera Leptodiaptomus and Mastigodiaptomus are the most speciose diaptomid genera in Mexico, and they inhabit natural and artificial lakes, ephemeral ponds, springs, and caverns. Leptodiaptomus is considered as an endemic Nearctic genus, whereas Mastigodiaptomus is a widely distributed Neotropical genus in the southern USA, Mexico, the Caribbean Islands and Central America. Based on new and recent evidence, Mastigodiaptomus diversity has been underestimated: six species of the genus were known before 2000. In this work three new Mastigodiaptomus species have been described from different regions of Mexico by using integrative taxonomy. We also gave amended diagnosis of M. nesus Bowman (1986) and M. patzcuarensis s. str. (Kiefer, 1938). Methods In this work, the taxonomic status of the species was clarified using modern, integrative method based on the COI gene as a DNA marker, plus micro-structural analysis (based on SEM and ligth microscopy). Results Three new species of Mastigodiaptomus were described based on genetic and morphological analyses: M. alexei sp. n., M. ha sp. n. and M. cihuatlan sp. n. Also amended description of M. nesus, morphological variation of M. patzcuarensis s. str., and a comparison of them with all known sequences within the genus are provided. These new findings show that in Mastigodiaptomus differences in several cuticular microstructures of several appendages (such as the antennules, the fifth legs, or the urosomites of these copepods) agree with the interspecific genetic divergence >3% observed in sequences of the COI gene, and the integration of this information is a powerful tool in species delineation.

A new species ofScapholeberisSchoedler, 1858 (Anomopoda: Daphniidae: Scapholeberinae) from the Colombian Amazon basin highlighted by DNA barcodes and morphology

“…We consider that detailed morphological analysis and the use of molecular tools, like DNA barcoding, will help to uncover the real identity of all these species, as the case presented here or with Scapholeberis duranguensis Quiroz-Vazquez & Elías-Gutiérrez, 2009, which was initially cited as S. rammneri by DeWaard et al (2006) and for which the closest species was S. freyi. The GMYC model used as a species delimitation method has been tested in other crustaceans as copepods (Gutierrez-Aguirre et al, 2020). It has been consequent with other methods as the BIN system and morphology, giving strong support to the modern description of species.…”

“…The best fit substitution model was TIM2+G, and it was replaced by GTR+G in MrBayes along with 1 M generations to obtain a tree. The Generalized Mixed Yule Coalescent (GMYC) method was applied as Gutierrez-Aguirre et al (2020) suggested to delimit the species. Finally, with the groups delimited by the GMYC technique, we calculated the mean estimates of evolutionary divergence over sequence pairs between groups.…”

Historical Composition of Zooplankton as an Indicator of Eutrophication in Tropical Aquatic Systems: the Case of Lake Amatitlán, Central America

“…From 1915 to 1997 cladocerans presented the highest species richness with 7 known species, followed by 3 calanoid copepods reported: A. dorsalis, Mastigodiaptomus albuquerquensis, and the endemic M. amatitlanensis [6,9,12,15]. This latter species is considered as a possibly extinct [16], because since its description date by Wilson (1941) [15] it has not been recorded, including this study. Additionaly we report for the first time in Amatitlán lake, two cyclopoid copepods, considered as exotic species for America: Thermocyclops crassus (Euro-Asiatic species) and M. thermocyclopoides (Afro-Asiatic species) [22,25].…”

“…With a historical and actual review of zooplankton biodiversity as well as an actual knowledge of the environmental conditions, we present the distribution, species richness, and spacial and temporal abundance of zooplankton and its relationship with environmental variables. We report the occurrence of two cyclopoid exotic species (Mesocyclops thermocyclopoides (Fischer, 1853) and Termocyclops crassus Harada, 1931) and the absence of the calanoid copepod Mastigodiaptomus amatitlanensis (Wilson, 1941) that was used to be recorded as endemic of the lake [15,16]…”

Dna Barcodes, a Powerful Tool for a Rapid Construction of a Baseline and Conservation of Aquatic Ecosystems in Sian Ka’an Reserve (Quintana Roo State, Mexico) And Adjacent Areas

“…We do not know anything about the biology of any zooplankter in this region. However, it was recently detected an apparent genetic structure in the haplotypes of M. siankaanensis from the center to the south of Yucatan [58], being different haplotypes and possibly in the process of differentiation.…”