Cerritulus gen. nov. can be morphologically distinguished from the remaining described doryctine genera from the American continent by having: 1) tibiae strongly curved on basal quarter, flat and rather wide, 2) femora considerably thick and wide and 3) ovipositor sheaths entirely swollen. This new genus shares most of the above features with the also monotypic, poorly known Oriental genera Ceylonspathius and Termitospathius, though it mainly differs from them by having: 1) all flagellomeres with placoid sensilla (without placoid sensilla in three or four basal flagellomeres in Ceylonspathius and Termitospathius, 2) fore femora with ventroapical rounded tubercle (with a ventroapical pointed tooth in Ceylonspathius and Termitospathius, 3) crenulate precoxal sulcus present (absent in Ceylonspathius and Termitospathius), 4) scutellar depression (scutal sulcus) densely, coarsely crenulated (mainly smooth in Ceylonspathius and Termitospathius) and 5) first metasomal tergite not petiolate, short and considerably wide (distinctly petiolate in Ceylonspathius and Termitospathius).
Cerritulus also differs from Termitospathius by the marginal (radial) cell of fore wing open apically (close in Termitospathius), first discal (discoidal) cell of fore wing distinctly petiolate anteriorly (sessile in Termitospathius), vein 1m-cu (recurrent) of fore wing antefurcal (distinctly postfurcal in Termitospathius) and subbasal (submedial) cell of hind wing distinctly long (short in Termitospathius). Wings in the single known specimen of Ceylonspathius are broken.
Cerritulus shares wing venation features with Embobracon van Achterberg, 1995, described from Panama (van Achterberg, 1995). However, Cerritulus distinctly differs from the latter genus in several other external morphological features, including the structure and shape of legs, structure of the first metasomal tergite, presence of precoxal sulcus and sternauli and presence of vein SC+R (second abscissa of costal vein) in the hind wing.