Pseudohaplogonaria cerasina Hooge, Smith & Iii, 2004, sp. nov.
Creators: name: Hooge, Matthew D.
name: Smith, Julian P. S.
name: Iii
Publisher: name: Zenodo
Year: 2004
Subjects: Biodiversity
Taxonomy
Animalia
Xenacoelomorpha
Acoelomorpha
Acoela
Haploposthiidae
Pseudohaplogonaria
Pseudohaplogonaria cerasina

description: Pseudohaplogonaria cerasina sp. nov. (Figs. 11–12)
Type Material: Syntypes. AMNH PLATY 1653 and AMNH PLATY 1654, two sets of 1.5­µm­thick serial oblique longitudinal sections of epoxy­embedded specimens stained with toluidine blue, collected October 2002.
Type Locality. Oak Island, NC, from shallow subtidal coarse to medium grained sand inside Lockwoods Folly Inlet (33° 54' 53"N, 78° 14' 06"W).
Other Material Examined. Living specimens in squeeze preparations; one whole mount for fluorescence imaging of musculature.
Etymology. Species name is from the Latin cerasinus, cherry­colored, and refers to the bright red rhabdoids in this species.
Description. Mature specimens approximately 650 µm long and 100 µm wide (Figs. 11, 12 A). Body cylindrical. Anterior and posterior ends rounded. Uncolored body by transmittted light.
Epidermis completely ciliated. Many bright red as well as uncolored rhabdoids present in body wall; mostly concentrated on ventral side (Fig. 11, 12 C).
Musculature with circular muscles that encircle the body along entire length of animal; straight longitudinal muscles present between frontal organ and anterior edge of mouth; longitudinal muscles with a longitudinal orientation anteriorly but then bend medially to cross diagonally over the body (longitudinal­cross­over fibers) present in both dorsal and ventral body wall; anterior end with ventral diagonal muscles positioned between outer circular and inner longitudinal muscles (data not shown).
Frontal organ well developed; cell bodies of frontal glands positioned ~250 µm behind frontal pore (Fig. 11 A, B).
Mouth opening on ventral surface, middle of body. Digestive central syncytium extends nearly entire length of body.
Ovary unpaired, ventral; extends from mouth posteriorly to bursal nozzle (Fig. 11 B).
Testes paired, dorsal, compact; separate from ovary. Testes extend anteriorly to position ~220 µm behind anterior tip and posteriorly to male copulatory organ.
Female gonopore and vagina absent. Seminal bursa leads to robust bursal nozzle ~30 µm in length (Figs. 11 B, C, 12B, D).
Male gonopore ventral, at posterior end; leads to non­muscular penis composed of spongy tissue with large nuclei (Figs. 11 C, 12B, D). Large masses of sperm present at lateral sides of penis; true seminal vesicle absent.
Remarks. Among species in the family Haploposthiidae, members of the genus Pseudohaplogonaria are united in having a seminal bursa with a sclerotized bursal nozzle, and a weakly developed or absent seminal vesicle. P. cerasina is most similar to P. minima (Ehlers & Dörjes, 1979), which also has paired testes, an unpaired ovary, conspicuous rhabdoids, and a bursal nozzle. P. minima, however, is more stout­bodied than P. cerasina, has a smaller male copulatory organ, and a common gonopore that opens to the seminal bursa via a short vagina.
description: Published as part of Hooge, Matthew D., Smith, Julian P. S. & Iii, 2004, New acoels (Acoela, Acoelomorpha) from North Carolina, pp. 1-24 in Zootaxa 442 on pages 16-18, DOI: 10.5281/zenodo.157611