Table 2. Relative abundance (± s.d.) of selected microbial genera in each howler group binned using the Ribosomal Database Project (RDP) multiclassifier with bootstrapping >70% across howler habitats and groups.

Genus	CR–Motiepa		CR–Balam		FR		SD–T2		SD–T1		Captive
	Mean (%)	s.d.	Mean (%)	s.d.	Mean (%)	s.d.	Mean (%)	s.d.	Mean (%)	s.d.	Mean (%)	s.d.
Bacteroides	0.003	0.002	0.002	0.002	0.014	0.015	0.000	0.000	0.003	0.006	0.186*	0.143
Blautia	1.009	0.180	0.875	0.144	0.374*	0.204	1.830	0.558	1.500	0.558	2.860	1.834
Butyricicoccus	0.269	0.097	0.268	0.232	0.156*	0.149	0.106	0.055	0.231	0.155	0.036*	0.044
Butyricimonas	0.000	0.000	0.000	0.000	0.000*	0.000	0.000	0.000	0.000	0.000	0.022*	0.013
Butyrivibrio	0.013	0.003	0.017	0.012	0.008	0.003	0.010	0.006	0.008	0.013	0.001*	0.002
Desulfovibrio	0.002	0.003	0.000	0.000	0.006*	0.003	0.002	0.002	0.000	0.002	0.000+	0.000
Lactobacillus	0.015	0.035	0.005	0.005	0.029+	0.018	0.001*	0.001	0.005*	0.004	0.282#	0.333
Marvinbryantia	0.127	0.037	0.108	0.045	0.083+	0.028	0.053*	0.012	0.038*	0.012	0.000#	0.000
Opitutus	0.007	0.003	0.003	0.002	0.026+	0.013	0.000*	0.000	0.000*	0.000	0.001*	0.002
Prevotella	0.052	0.027	0.037	0.011	0.007	0.008	0.003	0.003	0.016	0.014	9.177*	5.153
Pseudobutyrivibrio	0.000	0.000	0.000	0.000	0.000*	0.000	0.000	0.000	0.000	0.000	0.006*	0.007
Ruminococcus	0.510	0.234	0.384	0.178	0.808	0.406	0.302	0.350	0.565	0.504	0.231	0.351
Succinivibrio	0.000	0.000	0.000	0.000	0.001	0.001	0.000	0.000	0.000	0.000	2.255*	2.742

Abbreviations: CR, a continuous evergreen rainforest; FR, evergreen rainforest fragment; SD, semi-deciduous forest.

Symbols indicate significantly different abundances (t-tests, α=0.05). Abundances with matching symbols were not significantly different from each other.