Abstract
The original description of Neoechinorhynchus (N.) iraqensis Amin, Al-Sady, Mhaisen, Bassat, 2001, from Planiliza abu (Heckel) in the Euphrates River, Iraq, is updated and completed, for the first time, using ocular microscopy and SEM, despite its repeated discovery by various observers in Iraqi waters. No descriptive accounts were provided in these earlier reports. Structures originally described in line drawings are currently demonstrated considerably more clearly in life-like 3-dimensional forms. New morphological features constituting partial revision are reported herein for the first time. Proboscis hooks, anterior trunk topography, reproductive structures organization, and egg anatomy were particularly emphasized. The DNA sequence of the small subunit of nuclear ribosomal RNA (18S) was used to substantiate its morphological distinction. Maximum likelihood and Bayesian inference analyses were performed, which showed that Neoechinorhynchus (N.) iraqensis formed a clade with strong bootstrap support and Bayesian posterior probability.