Leptoclinides lotufoi, Oliveira & Carvalho & Rocha, 2019

Oliveira, Livia M., Carvalho, João Paulo & Rocha, Rosana M., 2019, Leptoclinides (Ascidiacea, Didemnidae) from Brazil: new records and two new species, European Journal of Taxonomy 572, pp. 1-16 : 8-10

Leptoclinides lotufoi sp. nov.

urn:lsid:zoobank.org:act:31D0C00F-2263-4826-8CEC-9782A1704D49

Fig. 3

Etymology

The name of this species is in homage to Dr Tito Lotufo for his studies in ascidian diversity in northeastern Brazil. He collected this material and lent it to us for this study.

Material examined

Holotype

BRAZIL • 1 colony; Rio de Janeiro, Angra Reis , Ilhota dos Porcos; 22°58′46″ S, 44°19′47″ W; 10 m depth; 10 Oct. 1998; T.M.C. Lotufo leg.; ColBio Tun 1245.

Description

The only colony found was attached to a exposed granitic substrate around 10 m deep. This colony was encrusting and small (2 cm wide, 1 mm thick), orange, but lost most of its color when fixed in formalin ( Fig. 3A ). The tunic is malleable and delicate, with a wide cloacal cavity that extends from the thorax to the region of the esophago-rectal peduncle. Only one common cloacal aperture was seen in this specimen; it is broad with a smooth margin. Spicules, in low density, almost unnoticeable, are mainly restricted to the surface layer of the tunic. Spicules are 20 to 30 µm in diameter, with 10–12 (in cross section) conical, pointed rays ( Fig. 3B ). SEM images of the spicules could not be made because of their scarcity and the small size of the colony.

Zooids are orangish, about 1.5 mm long. Twelve muscle fibers run longitudinally along each side of the thorax. The oral siphon is 0.15–0.33 mm long with six rounded lobes. The atrial aperture is very short and opens between the third and fourth rows of the pharyngeal stigmata. The pharyngeal stigmata formula is 10–12, 10, 10, 9–10 per half row. The lateral thoracic organ is round, not salient, usually at about the third row of stigmata, occasionally at the second row, close to the endostyle ( Fig. 3C ). The stomach is slightly elongated and is not overlapped by the intestinal loop. The testis has three oval follicles, overlain by three open turns of the sperm duct ( Fig. 3D ).

Most of the larvae we found were immature. Larvae are oval, yellowish, with about 0.8 mm in trunk length, without vesicles. The tail curves about halfway around the trunk. There are three anterior adhesive papillae with long peduncles. Nine to eleven short, digitiform ampullae are on each side of the larva. The sensorial vesicle is mid-dorsal, with the statocyte somewhat anterior and ventral to the ocellus ( Fig. 3E ).

Remarks

Although this species is being described from one single colony, its characters were different enough from those of other known species. Leptoclinides lotufoi sp. nov. is different from the other Atlantic congeners by having the following characteristics: few spicules restricted to the surface of the colony, few testicular follicles and turns of the sperm duct, and many ectodermal ampullae in the larvae. A few other species of Leptoclinides can have many ectodermal ampullae. The Australian L. brandi Kott, 2001 has a granular colony surface with a high density of spicules and smaller larvae with eight pairs of ampullae. Leptoclinides durus Kott, 2001 has many spicules and larger larvae with eight pairs of ampullae. Leptoclinides echinus Kott, 2001 has more testicular follicles (about 15) and larger larvae with eight pairs of ampullae. From New Caledonia, L. multipapillatus Monniot, 1989 has more testicular follicles, more turns of the sperm duct and more than 20 ectodermal ampullae ( Monniot 1989; Kott 2001).

Distribution

Type locality: Brazil: Rio de Janeiro.

Figures

Fig. 3. Leptoclinides lotufoi sp. nov., holotype (ColBio Tun 1245). A. Preserved colony. B. Spicules under light microscope. C. Thorax. D. Abdomen. E. Larva. Scale bars: A = 0.5 cm; B = 30 µm; C–E = 0.1 mm.