Enchiridium evelinae Marcus 1949

Bahia, Juliana, Padula, Vinicius, Lavrado, Helena Passeri & Quiroga, Sigmer, 2014, Taxonomy of Cotylea (Platyhelminthes: Polycladida) from Cabo Frio, southeastern Brazil, with the description of a new species, Zootaxa 3873 (5), pp. 495-525 : 511-512

Enchiridium evelinae Marcus 1949

( Figs. 13 and 14 )

Material examined. One specimen (MNRJ-PLAT 48, 26 x 10 mm) as sagittal sections of reproductive structures (16 slides), collected 27.10.2007 at Enseada 2, Ilha do Papagaio, Cabo Frio, Brazil (22°53'45.43"S, 41°59'5.54"W). Two specimens (MNRJ-PLAT 49, 31 x 10 mm; 44 x 11 mm), the larger as sagittal sections of reproductive structures (29 slides), collected 28.10.2007. One specimen (MNRJ-PLAT 50, 20 x 5 mm) collected 0 9.09.2007. Four specimens (MNRJ-PLAT 51, 33 x 10 mm; 25 x 9 mm; 19 x 5 mm; 6 x 4 mm) collected 0 8.12.2007. Two specimens (MNRJ-PLAT 53, 19 x 5 mm; 29 x 10 mm), the larger as sagittal sections of reproductive structures (14 slides), collected 20.04.2008. One specimen (MNRJ-PLAT 54, 26 x 6 mm) collected 21.04.2008. Three specimens (MNRJ-PLAT 56, 28 x 10 mm; 20 x 8 mm; 17 x 7 mm) collected 30.08.2008. One specimen (MNRJ-PLAT 58, 18 x 5 mm) collected 15.11.2008. Four specimens (MNRJ-PLAT 59, 32 x 14 mm; 26 x 10 mm; 30 x 13 mm; 22 x 9 mm) collected 13.12.2008. Two specimens (MNRJ-PLAT 60, 26 x 10 mm; 31 x 11 mm) collected 16.10.2009. All collected at Praia das Conchas, Cabo Frio, Brazil (22°52'33.05"S, 41°58'39.27"W). One specimen (MNRJ-PLAT 52, 23 x 8 mm) collected 10.12.2007. One specimen (MNRJ-PLAT 57, 24 x 9 mm) collected 0 1.09.2008. One specimen (MNRJ-PLAT 61, 17 x 9 mm) as sagittal sections of reproductive structures (14 slides) collected 18.06.2010. The three collected at Canal de Itajuru, Cabo Frio, Brazil (22º53’11’’S, 42º00’08’’W). One specimen (MNRJ-PLAT 55, 26 x 10 mm) as sagittal sections of reproductive structures (12 slides) collected 0 3.08.2008 at Saco do Mimi, Ilha do Papagaio, Cabo Frio, Brazil (22º53’51’’S, 41º58’52’’W). Depth: 6m. All specimens or parts preserved in ethanol 70%.

Distribution. Enchiridium evelinae was described from São Paulo State, Brazil (type locality; Marcus 1949); it was also reported from Curaçao ( Marcus & Marcus 1968), Panama (Rawlinson 2008), and recently from Rio Grande do Norte (Bahia et al. 2012).

Diagnosis. Long and narrow body; dorsal region cream with brown dots, more densely disposed at the median line; margin with orange dots; pharynx reaches 1/3 of the body length; seminal and prostatic vesicles highly muscularized; penis papilla and male atrium long.

Taxonomic remarks. We observed some differences between our specimens and those studied previously (Bahia et al. 2012), mostly related to dot arrangement, with some specimens having more densely clustered dots than others. ( Fig. 14 ). Nutritional status also influenced the coloration, with specimens that presented a full intestine being darker than ones with empty intestine. As we sampled a wider range of sizes we had variations in measures, but the proportion between them remained the same. Some specimens were found to have oviducts with oocytes that reached 130 µm in diameter. Characteristics observed in the specimens we studied are in accordance with the original description of Enchiridium evelinae ( Marcus 1949) . Specimens found in Cabo Frio (from 6 x 4 mm to 44 x 11 mm) reached larger sizes as originally described (15 x 3.3 mm) and later (33 x 8 mm) by Marcus & Marcus (1968).

Ecology. We found our specimens at the three sampled sites. This species was very frequent, which can indicate some adaptative trait, a probable generalist behavior, or more successful larval settlement.

Figures

FIGURE 13. Enchiridium evelinae (MNRJ-PLAT 49) A. in vivo; B. ventral view; C. sagital section of male reproductive structures; D. sagittal section of male and female structures. cg: cement glands; cp: cement pouch; fg: female gonopore; it: main intestine; ma: male atrium; mg: male gonopore; mo: mouth; pe: penis; ph: pharynx; pv: prostatic vesicle; st: stylet; su: sucker; sv: seminal vesicle; ut: uterus; va: vagina.

FIGURE 14. Color variation in Enchiridium evelinae. A. MNRJ-PLAT 51; B. MNRJ-PLAT 55; C. MNRJ-PLAT 51; D. MNRJ-PLAT 48; E. MNRJ-PLAT 57; F. MNRJ-PLAT 53; G. MNRJ-PLAT 59; H. MNRJ-PLAT 54.