diff --git a/Makefile b/Makefile
index 8a52da20b7796524e156f63922ed3a4d6f0034f8..d02bedf93dce0bf17a9e3d3b1d0c40791a24a2ef 100644
--- a/Makefile
+++ b/Makefile
@@ -4,5 +4,8 @@ test:testsuite/test_rep.sh
 	@testsuite/test_rep.sh testset1
 	@echo "all tests passed"
 
+test_y:
+	src/phybema.py --tools mash andi dnadiff -- testdata/Yersinia/
+
 clean:
 	@${RM} -r temp out
diff --git a/src/callProg.py b/src/callProg.py
index 3aff7d22cdfd79015e93f7d8999032990d4d9494..967c0cb77a6a04ee364f22c667b592252c9ff531 100644
--- a/src/callProg.py
+++ b/src/callProg.py
@@ -25,6 +25,7 @@ def run_prog(progname,call_list,fixed_out_file_name,progoutfilepath):
   sys.stderr.write("# starting program {}\n".format(progname))
   start_time = datetime.now()
   
+  sys.stderr.write(' '.join(call_list))
   try:
     output = subprocess.run(call_list,stdout=subprocess.PIPE,
                             stderr=subprocess.PIPE, universal_newlines=True)
diff --git a/src/parser.py b/src/parser.py
index 71fd9cca083b31330bd56462ebc23a037b5a0afe..16163eb47b3ec3255705c1f66c3fafe6f04d1587 100644
--- a/src/parser.py
+++ b/src/parser.py
@@ -7,13 +7,13 @@ to create a datatuplelist with the datasets and reftrees.
 author: Birgitta Päuker
 '''
 
-import argparse, os, sys
+import argparse, os, sys, re, subprocess
 from argparse import RawTextHelpFormatter
 from pathlib import Path
 from estimators import DistanceEstimator, estimator_choices
 from root_dir import phybema_root_dir
 
-FASTA_SUFFIXES = [".fasta",".faa",".fna"]
+FASTA_SUFFIXES = [".fasta",".faa",".fna",".fasta.gz"]
 REFTREE_SUFFIXES = [".nh",".tre"]
 
 # Function to parse the phybema options
@@ -92,8 +92,12 @@ def create_datatuplelist(datasetpaths):
       exit(1)
 
     # Create list of files with FASTA_SUFFIXES suffix
-    datafilepaths = [f.path for f in os.scandir(datasetpath) if Path(f).is_file
-                     and os.path.splitext(f)[1] in FASTA_SUFFIXES]
+    datafilepaths = list()
+    for f in os.scandir(datasetpath):
+      if Path(f).is_file:
+        for suffix in FASTA_SUFFIXES:
+          if re.search(r'{}$'.format(suffix),f.path):
+            datafilepaths.append(f.path) 
 
     # Check if a datafile was found
     if not datafilepaths:
@@ -113,6 +117,21 @@ def create_datatuplelist(datasetpaths):
         sys.stderr.write("{}: The found datafile {} is empty.\n"
                          .format(sys.argv[0], datafile))
         exit(1)
+      mo = re.search(r'(.*)\.gz$',datafile)
+      if mo:
+        uncompressed_file = "{}".format(mo.group(1))
+        if not os.path.isfile(uncompressed_file):
+          call_list = ['gzip','-k','-d',datafile]
+          sys.stderr.write('{}\n'.format(' '.join(call_list)))
+          try:
+            output = subprocess.run(call_list,stdout=subprocess.PIPE,
+                                    stderr=subprocess.PIPE, 
+                                    universal_newlines=True)
+          except: 
+            sys.stderr.write('{}: executing {} failed\n'
+                              .format(sys.argv[0],' '.join(call_list)))
+            exit(1)
+        datafile = uncompressed_file
 
     # Create list of files with REFTREE_SUFFIXES suffix
     reftreefilepaths = [f.path for f in os.scandir(datasetpath) if
diff --git a/testdata/Yersinia/.gitignore b/testdata/Yersinia/.gitignore
new file mode 100644
index 0000000000000000000000000000000000000000..83836288e2db3c96f2e4892241bc2a4a262ccc1b
--- /dev/null
+++ b/testdata/Yersinia/.gitignore
@@ -0,0 +1 @@
+sequence.fasta
diff --git a/testdata/Yersinia/sequence.fasta.gz b/testdata/Yersinia/sequence.fasta.gz
new file mode 100644
index 0000000000000000000000000000000000000000..facbeef9e71b92ea380bb59a863ed6bc771dbcd7
Binary files /dev/null and b/testdata/Yersinia/sequence.fasta.gz differ
diff --git a/testdata/Yersinia/tree.nh b/testdata/Yersinia/tree.nh
new file mode 100644
index 0000000000000000000000000000000000000000..6700166e0e58358bee8f9704bda928ea5dcff18d
--- /dev/null
+++ b/testdata/Yersinia/tree.nh
@@ -0,0 +1,4 @@
+(NC_008150:0.00006,((NC_008149:0.00006,NC_004088:0.00003):0.00003,
+(NC_005810:0.00021,((AAKT020000:0.00463,NC_006155:0.00213):0.00336,
+Pestis_F:0.00008):0.00003):0.00003):0.00003,
+NC_003143:0.00003);