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Hyalella azteca


Hyalella azteca is a freshwater epibenthic amphipod of interest to ecotoxicology and evolutionary biology. It is the primary invertebrate crustacean used in the U.S. for sediment toxicity testing and have been the subject of recent gene expression studies in ecotoxicogenomics.

H. azteca is a species complex which has diverged in North America over the past 11 million years creating numerous ecotypes which are the subject of divergent and convergent evolutionary studies.

Please cite the following publication when using the H. azteca genomes Hazt_1.0, Hazt_2.0, annotations BCMv0.5.3, and annotations OGSv1.0:
Community contact:

Image Credit: Helen Poynton. Image license: CC-BY 4.0.

Assembly Information

Analysis Name
Hyalella azteca genome assembly Hazt_2.0.1 (GCA_000764305.3)
AllPathsLG v. 48744; Atlas Link v. 1.0; Atlas GapFill v. 2.2; Redundans v. 0.11b (NA)
BioSample SAMN02978968
Date performed
Materials & Methods

Hazt_2.0.1 is an updated version of Hazt_2.0 ( Hazt_2.0 was resubmitted to NCBI with annotations, and in the process contaminants were removed from the assembly. See for more information. 

Assembly Metrics

Contig N50
Scaffold N50
GC Content

Data Files

NameLast modifiedSize
folder-parentParent Directory
folderBCM-After-Atlas2015-03-19 13:42
folderCurrent Genome Assembly2019-11-05 21:32
folderHazt_2.02018-09-24 11:54
folderHazt_2.0.12019-11-05 21:32