Schizochilus espinosai, Diez & Reygel & Artois, 2019

Diez, Yander L., Reygel, Patrick & Artois, Tom, 2019, Schizorhynchia (Platyhelminthes, Rhabdocoela) from eastern Cuba, with the description of fifteen new species, Zootaxa 4646 (1), pp. 1-30 : 21-22

Schizochilus espinosai sp. n.

( Fig. 12 A–B, 15E)

http://zoobank.org/ urn:lsid:zoobank.org:act:2CF67117-9665-4779-96D4-2B0A4272D392

Material. One specimen studied alive and whole mounted, designated holotype ( FMNH https://id.luomus.fi/ KV.617), collected in Bueycabón (type locality) (February 21, 2018), sublittoral, fine-grained sand with organic matter, 0.5 m depth, salinity 33 ‰.

Etymology. Species dedicated to Prof. Em. Dr. José Espinosa Sáez (Instituto de Ciencias del Mar, La Habana, Cuba), specialist in ecology and taxonomy of molluscs, and awarded with the National Award of Marine Sciences of Cuba (2018).

Diagnosis. Species of Schizochilus with a spiny cirrus 71 μm long; spines talon-shaped, about 3 μm long. A 52-μm-long, needle-shaped stylet runs centrally through the cirrus. Copulatory bulb distally forming a 12-μm-long cap.

Description. Animal 0.9 mm long, measured on the whole mount, translucent, without eyes. Proboscis lips ( Fig. 12A : pr) 77–92 μm long (x = 85 μm; n = 2), with a pair of caudal glands. Pharynx ( Fig. 12A : ph) 72 μm in diameter, located at 70%.

Four testes ( Fig. 12A : t) lie in a row rostrally from the pharynx, fused two by two into two pairs. Copulatory bulb ( Fig. 12A : cb, 15E) 77 μm long, comprising the prostate vesicle and the spiny cirrus. The cirrus is 71 μm long and 6 μm wide, measured over its midlength. The spines are talon-shaped and about 2–3 μm long (x = 3 μm; n = 2). A 52-µm-long stylet ( Fig. 12B ) runs centrally through the cirrus. It is 6 μm wide proximally, needle shaped, and tapers to a distal sharp point. The copulatory bulb forms a distal sclerotized cap of 12 μm long and 9 μm wide at the widest point. As such, it surrounds the cirrus for 23% of the latter’s length. The common gonopore ( Fig. 12A : cg) opens at 90%.

A pair of vitellaria ( Fig. 12A : vi) extend between the brain ( Fig. 12A : br) and the copulatory bulb, one vitellarium at each side of the body. A bursa ( Fig. 12A : b) and ovary ( Fig. 12A : ov) are located in the caudal body end. The uterus ( Fig. 12A : ut) is directed forwards, situated beside the copulatory bulb.

Figures

FIGURE 12. Schizochilus espinosai sp. n.. A, body from the live animal. B, cirrus and stylet. Schizochilus atlanticus sp. n.. C–D, cirrus and stylet. Schizochilus bueycabonensis sp. n.. E–F, stylet. Schizochilus banesensis, sp. n.. G, cirrus and stylet. Schizochilus maximus sp. n.. H, cirrus and stylet. B–H, from whole mounts. B–C, F–H, from the holotype. D, E, from a Reference specimen (HU X.1.22).