Proporus carolinensis, Hooge, Matthew D., Smith, Julian P. S. & Iii, 2004

Hooge, Matthew D., Smith, Julian P. S. & Iii, 2004, New acoels (Acoela, Acoelomorpha) from North Carolina, Zootaxa 442, pp. 1-24 : 19-21

publication ID	https://doi.org/ 10.5281/zenodo.157611
DOI	https://doi.org/10.5281/zenodo.6273414
persistent identifier	https://treatment.plazi.org/id/03CE390F-560F-FF86-FEC3-CA0B313732E5
treatment provided by	Plazi
scientific name	Proporus carolinensis
status	sp. nov.

Treatment

Proporus carolinensis View in CoL sp. nov. ( Figs. 13–15 View FIGURE 13 View FIGURE 14 View FIGURE 15 )

Type Material: Syntypes. AMNH PLATY 1655 and AMNH PLATY 1656, two sets of 1.5µmthick serial sagittal sections of epoxyembedded specimens stained with toluidine blue, collected October 2002. Paratype. AMNH PLATY 1657, epoxyembedded whole mount.

Type Locality. Oak Island, NC, from shallow subtidal medium grained sand at the Lockwoods Folly Inlet (33° 55' 03"N, 78° 13' 58"W).

Other Material Examined. Living specimens in squeeze preparations; one whole mount for fluorescence imaging of musculature.

Etymology. Species name refers to North Carolina, the state from which the type material was collected.

Description. Mature specimens 650 to 800 µm long and ~150 µm wide ( Figs. 13 View FIGURE 13 , 14 View FIGURE 14 A, 15A). Specimens fixed for histological sectioning contracted considerably.

Body cylindrical. Anterior end rounded, posterior end tapers to blunt point.

Epidermis completely ciliated. Two types of rhabdoid glands present in epithelium; one large and cylindrically shaped, the other smaller with an irregular shape ( Fig. 13 View FIGURE 13 , 14 View FIGURE 14 B).

Bodywall musculature a simple gridwork of outer circular muscles and inner longitudinal muscles ( Fig. 15 View FIGURE 15 C).

Frontal organ well developed; cell bodies of frontal glands positioned ~150 µm behind frontal pore in fixed specimens ( Fig. 13 View FIGURE 13 ).

Mouth opening on ventral surface, anterior half of body; usually posterior to statocyst ( Fig 13 View FIGURE 13 , 14 View FIGURE 14 A, 15A), in one fixed specimen mouth opening extended anterior to level of statocyst ( Fig. 15 View FIGURE 15 A). Mouth opens to ciliated pharynx with welldeveloped circular and longitudinal muscle fibers ( Fig. 13 View FIGURE 13 , 15 View FIGURE 15 A, C, D). Digestive central syncytium extends from frontal glands to posterior end of body.

Ovary unpaired, ventral; extends from level of pharynx posterior to middle of body. ( Fig. 13 View FIGURE 13 ). Eggs not present in all examined specimens ( Fig. 15 View FIGURE 15 A).

Testes paired, dorsal, follicular; separate from ovary. Testes extend posteriorly from position behind frontal glands to seminal vesicle ( Figs. 13 View FIGURE 13 , 15 View FIGURE 15 A, B).

Female gonopore absent. Male gonopore terminal at posterior end opens to ciliated, tubular male antrum ( Figs. 13 View FIGURE 13 , 15 View FIGURE 15 B). Wall of antrum with circular and longitudinal muscles, lined with nuclei, but without obvious glands. Proximal end of antrum opens to seminal vesicle with sperm arranged in parallel with longitudinal body axis ( Figs. 14 View FIGURE 14 A, 15B).

Remarks. Proporus carolinensis appears to be most similar to P. lonchitus and P. minimus . These three species have pharynges that open posterior to the level of the statocyst; this is unlike the condition found in the other three known species of Proporus in which the mouth is located anterior to the statocyst. In addition, P. carolinensis and P. l o n chitus are the only known species in the genus to have paired testes. In contrast, P. c a ro linensis lacks the gut musculature found in P. minimus , and the glands surrounding the pharynx of P. lonchitus . Most importantly, P. carolinensis does not have glands opening into the male antrum, as is the case in all other known species in the genus.

Proporus carolinensis View in CoL lacks accessory muscles that fan out from the mouth opening as found in another species of the Proporidae View in CoL , Proporus bermudensis Hooge & Tyler, 2001 View in CoL , and other pharynxbearing turbellarians such as Macrostomum hystricinum View in CoL (see Rieger et al. 1994).