State of knowledge of the Acotylea (Polycladida, Platyhelminthes) from the Mediterranean coasts of Spain: new records and new species
Author
Marquina, Daniel
Author
Osca, David
Author
Rodríguez, Jorge
Author
Fernández-Despiau, Estrella
Author
Noreña, Carolina
text
Zootaxa
2014
3780
1
108
134
journal article
46182
10.11646/zootaxa.3780.1.4
575e1e54-5332-4e35-bcc3-dc9daa320948
1175-5326
250025
E1E25433-72CD-4592-B9C2-62F4D11F2D82
Trigonoporus cephalophtalmus
Lang, 1884
Figs. 1
(3), 6, 7
Material examined.
Three mature specimens, collected in the Columbretes and Hormigas Islands and Alborán Island from rocky substrate found at 14.3, 23.5 and 36 metres deep, respectively for each location;
Fig. 1
(3).
Description.
Fixed specimen is approximately
2 cm
long by
5 mm
wide. Very elongated body. Colour whitishyellow, partially lost during conservation, with numerous and small brown spots (
Fig. 6
A). Region between the brain and the anterior margin strewn with numerous small eyes spreading out in a fan-like manner (
Fig. 6
B). Marginal eyes arranged along the frontal margin of the body. Tentacles and tentacular eyes lacking. Brain located about
2 mm
from the anterior margin (
Figs. 6
C, 7C). Ruffled pharynx situated in the middle third of the body with the oral pore opening in the centre of it. Ovaries dorsal. Separated gonopores (
Fig. 6
C).
Male copulatory complex directed backwards, near the pharyngeal cavity (
Fig. 6
D).
Vasa deferentia
occupy the middle third of the body due to being dilated, and open laterally into a tubular seminal vesicle thickened in the junctions region (
Figs. 6
D, 7D).The ejaculatory duct runs ventrally from the seminal vesicle to the proximal end of the prostatic vesicle. The prostatic vesicle has a strong muscular envelope and is lined with a smooth and folded glandular epithelium (
Fig. 7
B). The penis papilla, small and unarmed, is conical-shaped, with a strong muscular envelope, housed in a wide, ciliated atrium.
The epidermis around the female pore appears corrugated, forming an adhesive pad (
Figs. 6
D, 7A). The female system consists of an external and internal vagina. The short narrow external vagina runs from the gonopore upwardsto the internal vagina. The internal vagina ascends from the proximal region of the external vagina, curves downwards and backwards and, after receiving the oviducts, continues to the
ductus vaginalis
. Oviducts lead separately into the middle of the internal vagina. Proximal tract of the internal vagina runs forwards, receiving secretions from the well developed cement glands. Lang’s vesicle lacking. The
ductus vaginalis
opens to the exterior behind the female pore.
Distribution.
Trigonoporus cephalophtalmus
has only been found once in the Gulf of Naples,
Italy
(
Lang 1884
). This is the first record for this species both outside of the Gulf of Naples and for the Iberian Peninsula.