Notocomplana ferruginea

Notocomplana ferruginea (Schmarda, 1859) Fig. 22 Material examined. Yucatan coast, Mexico • 1; Arrecife Alacranes; 22.4°N, 89.7°W; 1 m; 4 Nov. 2017; A. Hernández leg.; CRPPY -0004; Veracruz coast, Mexico • 6; Veracruz; 19.2°N, 96.1°W; 1 m; 31 Sep. 2018; A. Hernández leg.; CRPPY -0101 • 7; Veracruz; 19.2°N, 96.1°W; 2 m; 1 Sep. 2018; A. Hernández leg.; CRPPY -0103. Distribution. The species was described from Jamaica (Schmarda 1859); Colombia, Antilles, and Bahamas (Hyman 1955; Marcus and Marcus 1968; Quiroga et al. 2004 a, 2004 b). New record for the coasts of Veracruz and Yucatán. New record for the Gulf of Mexico. Description. Body shape oval with rounded anterior and tapered posterior end, margins pale, wavy, 2.5 cm in length and 1 cm in width. Translucent beige colouration, darker in the middle region of the pharynx (Fig. 22 A). Two groups of well-defined cerebral and tentacular eyes (Fig. 23 B). No marginal eyes. A short stylet is present. Prostatic vesicle interpolated. Male atrium very muscular. An elongated atrium, a muscular vagina externa and interna as well as Lang’s vesicle form the female copulatory apparatus (Fig. 22 C, D). Remarks. Research conducted by Oya and Kajihara (2017) and Litvaitis et al. (2019) has led to the transfer of species within Melloplana, a genus belonging to the family Pleioplanidae, to the genus Notocomplana (family Notoplanidae). This transfer is based on analysis of the mitochondrial gene Cox 1 (Oya and Kajihara 2017) and the nuclear gene 28 S (Litvaitis et al. 2019). Only a few morphological differences between Melloplana and Notocomplana have been identified. The main distinction lies in the orientation of the prostatic vesicle chambers: Melloplana prostatic chambers are perpendicular to the intra-vesicular ejaculatory duct, whereas Notocomplana chambers are longitudinally arranged (Faubel 1983). However, both Melloplana and Notocomplana lack a stylet. Considering the limited morphological variation between the genera and recent molecular analyses, there is a tendency to propose eliminating the genus Melloplana, as well as the family Pleioplanidae. However, Pleioplanidae also includes other genera like Izmira, Pleioplana, and Laqueusplana, which are poorly known. Therefore, additional molecular analyses and morphological evidence are necessary to confirm the elimination of the family Pleioplanidae (Dittmann et al. 2019).