First record of Triops cancriformis (Branchiopoda: Notostraca) in Qatar: Its origin and range expansion inferred from genetics, morphology, and reproduction
Data files
Dec 12, 2025 version files 9.75 KB
Abstract
The presence of Triops cancriformis has not been broadly reported outside Europe or North Africa. Among the few exceptions, including the studies on the Middle Eastern populations, genetic information is almost completely absent. This study confirms the presence of T. cancriformis as a single population in Rawdat Nu’man, Qatar, using both morphological and genetic data. The dataset focuses on the morphological traits in members of this only population of the species in Qatar. Their carina and telson were consistent with the traits in the subspecies of T. c. simplex, while their COI and 16S sequence analysis revealed that the population of Rawdat Nu’man is consistent with T. c. cancriformis. As this morphology vs. genetics inconsistency has been reported previously, the observation in the Qatari T. cancriformis further calls for reassessment of the status of the two subspecies. The COI-based phylogeny shows the Nu’man population being most closely related to a population in Königswartha, Germany. Further, the presence of only female individuals, the absence of genetic diversity, and limited local distribution indicate recent colonization in Qatar, possibly through passive dispersal via diapausing cysts carried by avian vectors during seasonal migrations.
Dataset DOI: 10.5061/dryad.0zpc8679n
Description of the data and file structure
These are morphometric data of the tadpole shrimp Triops cancriformis in Qatar. Data are listed by each individual specimen for a total of 106 wild-caught individuals and 8 lab-raised specimens. Wild-caught specimens were used to measure their carapace length, carapace width, carapace height, abdominal length (as Tail length or TL), furca length, all in millimeters. The number of thoracic segment, abdominal segment, and apodal segments of the abdomen were discrete numbers without unit. Sex and gravid status were also included. Lab-raised specimens were used to measure only the ratio of caudal length to carapace length and to identify their sex.
There are two sets of raw data: the morphometry of Triops cancriformis (Morphometrics_Triops_cancriformis-Dryad.csv)and the accession numbers of the sequences obtained from NCBI (Accession_numbers_of_sequences_obtained_on_NCBI.txt).
Morphometrics_Triops_cancriformis-Dryad.csv
Data are listed by each individual specimens collected on four separate dates. Each column indicates the individual specimen collected on the specific date. Each row specifies the morphological traits being measured. Traits measured include the carapace length, carapace width, carapace height, abdominal length (as Tail length or TL), and furca length, all in millimeters. The number of thoracic segment, abdominal segment, and apodal segment of the abdomen were in discrete numbers without unit. The gravidity status were also included. There were a total of 106 wild-caught individuals.
Accession_numbers_of_sequences_obtained_on_NCBI.txt
This table lists the accession numbers of the COI gene sequences and the 16S gene sequences obtained from the NCBI databases. These sequences and the sequence from the Qatari T. cancriformis were analyzed phylogenetically to understand the relationship between the Qatari T. cancriformis population and the populations from other geographic locations.
Morphometry of each specimen was made by measuring the length, width, and depth of the carapace, as well as the length of the exposed abdomen and the furca. The length of the carapace was measured from the anterior terminus along the carina to reach to the sulcus, the width as the widest span, and depth as the greatest thickness of the carapace. In addition, the carina was also subject to assessment for the presence of ridges or spikes.