Skip to main content

Pernambucano worm (Spirobolbolaimus pernambucanus) and Graciele worm (Ixonema gracieleae) from South Atlantic

Pernambucano worm (Spirobolbolaimus pernambucanus) and Graciele worm (Ixonema gracieleae) from South Atlantic

NEWS - New species of Microlaimidae were discovered in sediment samples collected in the South Atlantic, along the continental shelf separating Northeastern Brazil. Pernambucano worm (Spirobolbolaimus pernambucanus) has six outer labial setae and four cephalic setae of almost equal length. Graciele worm (Ixonema gracieleae) has somatic setae on peduncles.

Both are the first species of the genus described from the South Atlantic and greatly contribute to the knowledge and variability of these two genera. The number of Microlaimidae species initially described from sediment samples collected on the Brazilian coast shows that great efforts are still needed to fully understand the richness of continental margins such as the Brazilian coast.

Pernambucanus is the Latin form of the term “pernambucano”. In Brazil, “pernambucano” refers to something or someone originating from the state of Pernambuco. I. gracieleae received its specific epithet in honor of Graciele Mariza dos Santos Alves, wife of the first author.

S. pernambucanus differs from S. undulatus in its length of 1,686-1,848 µm (vs. 2,035-2,558 µm in S. undulatus), absence of articulated outer labial setae (vs. articulated outer labial setae), presence of an outer labial setae nearly as long as the cephalic setae (vs. longer outer labial setae than the cephalic setae), 12 pore-like precloacal supplements (vs. 18-19 precloacal supplements in a series of mid-ventral elevations with pores at the top) and absence of additional teeth (vs. present).

S. pernambucanus differs from S. boucherorum in having 12 precloacal appendages (vs. 7 in S. boucherorum), a gubernaculum length of 19-19.5 µm (vs. 23-30 µm) and the presence of an outer labial seta that is nearly as long as the cephalic seta (vs. the outer labial seta being longer than the cephalic seta).

I. gracieleae differs from Bathynox in having three caudal glands that open through separate outlets in papilla-like extensions (vs. three glands opening in a single outlet), males are diorchid (vs. monorchic) and the gubernaculum lacks an apophysis (vs. the presence of a dorsal apophysis).

I. gracieleae differs from I. powelli by the circular shape of the amphidia fovea (vs. pouch-like in I. powelli), 6 rows of cervical setae (vs. 4 rows of cervical setae) and a gubernaculum 11.5–14.5 µm long (vs. ca. 6 µm). I. gracieleae differs from I. sordidum by having long somatic setae alternating with short somatic setae along the body and the presence of a precloacal supplement.

I. gracieleae differs from I. deleyi by the presence of a gubernaculum (vs. absent in I. deleyi) and a ventral jointed seta located immediately behind the pharynx + two jointed setae closer to the cloaca and a smaller non-continuous seta further away (vs. one non-continuous ventral precloacal seta).

Original research

Manoel A, Neres PF, Esteves AM. 2024. Two new species of Microlaimidae (Nematoda: Microlaimida) from the Continental Shelf off Northeastern Brazil (Atlantic Ocean) with emended diagnosis and dichotomous key. PeerJ 12:e17976, DOI:10.7717/peerj.17976

Dlium theDlium

Popular Posts

Cockspur coral tree (Erythrina crista-galli)

Velvet coral tree or cockspur coral tree ( Erythrina crista-galli ) is a species of plant in the Fabaceae family. It is a small tree, 5-8 meters tall, with a trunk circumference of about 50 cm, irregular branches, light wood, and fissured, soft, and light brown bark. The taproot is white. The leaves are ovate, with three strands, dark green and glossy on the upper surface, and pale green on the underside. The central lobe is up to 17 cm long and up to 11 cm wide. The left and right lobes are up to 15 cm long and up to 10 cm wide. The flowers are red, arranged in racemes, at the apex, pentameric, complete, and bilaterally symmetrical. The flowers are up to 6 cm long and 4 cm wide. The pods are long, containing about 8 seeds, green when young and turning brown as they mature. The seeds are ovate, flat, and brown. It grows well in lowlands up to an elevation of 1,500 meters, with an annual rainfall of 800-1,500 mm/year, and a temperature of 20-32°C. It thrives in well-drained soils, but...

Tanglehead (Heteropogon contortus)

Tanglehead ( Heteropogon contortus ) is a species of Poaceae, an erect grass, up to 65 cm tall, with leaves up to 13 cm long and 0.5 cm wide. The inflorescence is at the top and hairy. The tip is black. This plant forms dense colonies in forests, agricultural lands, roadsides, and abandoned areas. TAXON : Kingdom: Plantae Phylum: Tracheophyta Subphylum: Angiospermae Class: Liliopsida Order: Poales Family: Poaceae Subfamily: Panicoideae Tribe: Andropogoneae Subtribe: Anthistiriinae Genus: Heteropogon Pers. in Syn. Pl. 2: 533 (1807) Species: Heteropogon contortus (L.) P.Beauv. in J.J.Roemer & J.A.Schultes, Syst. Veg., ed. 15[bis]. 2: 836 (1817) HOMOTYPIC SYNONYMS : Andropogon contortus L. in Sp. Pl.: 1045 (1753) Heteropogon contortus var. hirtus Hack. in C.F.P.von Martius & auct. suc. (eds.), Fl. Bras. 2(3): 267 (1883) Heteropogon hirtus Pers. (1807) Holcus contortus (L.) Stuck. in Anales Mus. Nac. Buenos Aires, ser. 3, 4: 48 (1904) Sorghum contortum (L.) Kuntze in Revis. Gen. ...

Humpback whales (Megaptera novaeangliae) manufacture bubble-nets as tools to increase prey intake

NEWS - Humpback whales ( Megaptera novaeangliae ) create bubble net tools while foraging, consisting of internal tangential rings, and actively control the number of rings, their size, depth and horizontal spacing between the surrounding bubbles. These structural elements of the net increase prey intake sevenfold. Researchers have known that humpback whales create “bubble nets” for hunting, but the new report shows that the animals also manipulate them in a variety of ways to maximize catches. The behavior places humpbacks among the rare animals that make and use their own tools. “Many animals use tools to help them find food, but very few actually make or modify these tools themselves,” said Lars Bejder, director of the Marine Mammal Research Program (MMRP), University of Hawaii at Manoa. “Humpback whales in southeast Alaska create elaborate bubble nets to catch krill. They skillfully blow bubbles in patterns that form a web with internal rings. They actively control details such ...