Pachysphinx modesta (Harris, 1839)

Thorax unicolorous as in Amorpha. Bristles of the pilifer modified mostly to hair-scales. Abdominal tergites are spinose all over, the spines as stout as in Amorpha, less weak than in Sphinx. Anterior tibia ending in a heavy thorn. Frenulum vestigal. Forewing upperside with pattern of five lines in the middle area, like in Amorpha, but the second (within the dark band) is always absent, and the third seldom obvious, forth and fifth are crenate as in Amorpha. Forewing underside with basal area red as in Sphinx. Hindwing upperside red as in Sphinx, colouration intensified subbasally behind the cell forming a patch. Antenna long, strongly compressed, slightly dilated laterad as in Sphinx ocellata., ciliae long. Antenna thin, proximal edges of the segments feebly raised, dorso-lateral expansions of males barely vestigal in females, a proximal series of very slightly prolonged ciliae, surface of segments feebly concave laterally and ventrally. Gnathos broader than in Sphinx and Amorpha, with almost parallel sides. Valve very broad, very obtuse, dilated dorsad at apex; the end of abdomen appearing truncate. Harpe large, ventro-distally produced into two lobes; the dorsal edge of the harpe raised into a broad lobe, which is rough with short pointed tubercules and teeth. Juxta short, without process. Aedeagus comparatively slender and weak without external armature; a conical tooth upon the membrane of the duct inside the sheath. No retinaculum. Vaginal plate with a low thick ridge before the vaginal cavity, without lobes, antevaginal portion of the plate short; the whole eighth segment strongly chitinised.