Prosternum in front of coxae without paired lines or carinae.

Prosternum is well developed, divided into two lobes.

The head and pronotum are granulate, the prosternum is rudimentary, without intercoxal processes.

The extension of the prosternum is broad, with a truncated tip, ending adjacent to the metasternal process.

Procoxae not or slightly projecting below prosternum.

Prosternum smooth, impunctate, covered with uniform, appressed, white or tawny pubescence.

The prosternum is triangular, and extended laterally to the propleuron as a narrow, precoxal bridge.

Anterior edge of prosternum without mesal excavation.

Forechest, commencing at the prosternum, should be well filled and carried well down between the legs with no sense of hollowness.

Anterior edge of prosternum not produced anteriorly, or distinctly produced forming chin piece (rare).

Prosternum in front of coxae concave or biconcave, or flat to moderately convex.

Black setae can be found on both the propleuron and the hypopleuron, with brown setae on the prosternum.

In general the coloration of the beetle was a uniform dark grey, with setae in some ares of the prosternum.

Poorly constructed fronts which are too upright in shoulder, lack prosternum and the chest-fill between the front legs and have loosely connected elbows.

The body proportions are slightly off square, meaning that the dog is slightly longer from prosternum to buttocks as he is from withers to ground.

The length of body, from prosternum to the rear-most projection of the rump, is slightly longer than the height of the dog at the withers.

Paropsides belongs to the Paropsis-group of genera, with similar head, appendages, prosternum, elytra, tarsi and larva.

Thorax: Prosternum that has two moderate blunt spines; meso-and metasternum considerably wide, but do not have distinct lateral lobes.

The Portuguese Water Dog is off-square, slightly longer than tall when measured from prosternum to rearmost point of the buttocks, and from withers to ground.

In general Pygidicranids also have equally sized ventral cervical sclerites, and in having the rearmost sclerite separated from, or only touching the center of the prosternum.

The ventral view or sternum follows the same convention, with the prosternum under the prothorax, the mesosternum under the mesothorax and the metasternum under the metathorax.

A spine on the prosternum can be snapped into a corresponding notch on the mesosternum, producing a violent "click" that can bounce the beetle into the air.

Anterior portion of prosternum at midline shorter than prosternal process, or as long as prosternal process, or longer than prosternal process.

The most distinctive feature of the family is that the tip of the rostrum fits into a groove in the prosternum, where it may be used for stridulation by rasping it against ridges in the groove.