Yucatania clavus a new genus and new species for the family Thrombidae is reported from the continental shelf off the Yucatan Peninsula, Mexico. It is the second genus of the family, which is characterized by the presence of a new skeletal character, based on reduced triaenes, which are here termed “demotriaenes,” and constituting the main megasclere spicule. These are arranged in a radial palisade pattern at the periphery with a confused architecture in the choanosome. In addition, Yucatania has the typical skeletal megascleres of the family, i.e., the small acanthotriaene, in addition to the amphiaster type. These characteristics are established to include the type species: Y. clavus. Thrombus, the sole genus of the family up to now, is distinct from Yucatania by possessing a single spicule type, i.e., the small acanthotriaenes. These are arranged with the cladomes tangential to the surface, without reaching a radial or a palisade structure, and only two of the five members of it bear the amphiaster type. A redescription of the family Thrombidae is here included.

The study of Syllidae (Polychaeta) from the southwest Atlantic Ocean revealed the presence of an unknown species, which is herein described as Haplosyllis loboi, new species. According to its morphology, the new species belongs to the species-complex group of Haplosyllis spongicola (Grube, 1855). However, it is distinguished by the presence of a series of denticles between the upper end of the main fang and the lower end of the subdistal tooth and the shape of the dorsal cirri, which are shorter than the body width and tapered, showing slightly alternating lengths. The description of this new species of Haplosyllis supports the growing evidence that H. spongicola, formerly considered to be a cosmopolitan species, has in fact been used for several distinct species.

A new species of the genus Benthoctopus is described and illustrated based on 14 specimens collected from the coast of Central Chile and the Juan Fernández Archipelago, at depths between 436 and 1000 m. This medium sized species (total length between 425 and 770 mm) has no ink sac and presents the following attributes: small biserial suckers; large eyes (diameter between 11 and 23 mm); the first pair of arms longer than the other arms; 63 to 75 suckers in the hectocotylized arm; eight to nine lamellae per demibranch and a W-shaped funnel organ. This new species, which we call Benthoctopus longibrachus, is compared to other species in the genus.

We describe here Magnapinna atlantica, a new species of oegopsid squid in the Magnapinnidae. This is the second described species in the family. The new species is based on two specimens, one of which is in excellent condition. This species has the following characters that are unique within the family: Tentacles more slender than adjacent arms, and proximal region of tentacles without suckers and bearing large glandular swellings. A third species is described but not named due to the poor condition of the squid. We also transfer Mastigoteuthis talismani to the Magnapinnidae, along with another squid, long known in the literature but incorrectly identified.

Loboixys ryukyuensis, a new genus and species of the family Notodelphyidae, is described based on females living in the compound ascidian Diplosoma virens (Hartmeyer). The host was collected on the coral reef in Okinawa, Ryukyu Archipelago, Japan. Among notodelphyids, most of which are associated with compound ascidians, the new copepod closely resembles, in morphology, species of Doroixys Kerschner, 1879. In comparison with all known species of Doroixys and two other allied notodelphyid genera, this copepod can be assigned to a new genus on the basis of the following characters: the inflated body is lobed, the antennule is indistinctly 7-segmented, the labrum has four lobes, the fifth leg consists of one inner seta and a 2-segmented outer lobe with one seta, and the setiferous caudal ramus is extremely reduced.

Thirty-two species of pelagic decapod shrimps are recorded from 57 stations off the southeastern coast of South Africa. The material was trawled from between 200 m and the surface. The assemblage includes typical shelf forms like Solenocera africana Stebbing, 1917 and Pasiphaea semispinosa Holthuis, 1951, as well as typically oceanic species of Sergestes H. Milne Edwards, 1830, Sergia Stimpson, 1860 and Gennadas Bate, 1881. Several species seem to co-occur consistently, especially in the oceanic component of the fauna.

The goal of the present study was to investigate the growth rate of the crab Dissodactylus crinitichelis, its molt increments, and the duration of the intermolt intervals under laboratory conditions, focusing on differences between sexes and between juvenile and adult phases. Crabs were collected at Flamengo Beach, Ubatuba, São Paulo State, Brazil, by scuba divers. In the laboratory, individuals were maintained in isolation and fed nauplii of Artemia sp. daily. The sex and carapace width of exuviae and dead crabs were recorded. During the juvenile phase, mean growth was 11.8 ± 2.7% in males and 11.2 ± 3.6% in females, with their respective intermolt intervals 25.4 ± 9.2 and 26.4 ± 8.3 d (mean ± SD). After reaching morphological sexual maturity, the intermolt intervals increased to 33.4 ± 10.1 d in males and 32.7 ± 10.4 d in females, and the growth rates of both sexes slowed to 6.4 ± 1.9% in males and 5.7 ± 1.6% in females. There was a significant decrease in molt increment and an increase in intermolt intervals associated with the maturation from juveniles to adults, evidencing differential energy allocation during the last phase of ontogeny.

Meganthias carpenteri is described from two specimens collected off Nigeria. An additional specimen of Meganthias, caught in the eastern South Atlantic over Vema Seamount, is considered, as is M. natalensis, the type species of the genus. The three Atlantic specimens of Meganthias are the first of the genus recorded from that ocean. Previously described species of Meganthias are M. natalensis (western Indian Ocean) and M. kingyo (Ryukyu Islands, western Pacific). Meganthias carpenteri differs from them in the morphology of the lips and maxilla.

The morphologies of three unusual tadpoles from slow-flowing, sandy-bottomed, rain forest streams in southeastern Madagascar are described. The large oral apparatus of the tadpole of Boophis picturatus Glaw, Vences, Andreone, and Vallan, 2001 lacks all keratinized structures and has an elaborately-folded lower labium with five, radially oriented, flat-topped ridges.

The tadpole of Mantidactylus guttulatus (Boulenger, 1881) lacks all keratinized mouthparts and has three immense papillae where the upper jaw normally occurs.

The tadpole of Mantidactylus lugubris (Duméril, 1853) has an ornate oral apparatus involving greatly hypertrophied derivatives of jaw serrations and unique structures on the lower labium that resemble labial teeth.

The foliar flavonoid content of 142 individual pine trees (Pinus leiophylla, P. chihuahuana and P. lumholtzii) was analyzed by paper chromatography and ultraviolet spectroscopy with the aim of determining the ability of foliar profiles of flavonoids to distinguish closely related pine species and to determine if Pinus chihuahuana should be recognized as a distinct species or as a variety of P. leiophylla. The flavonoid composition of needles was evaluated within and among the taxa using Principal Coordinates Analysis (PCO). The results support the recognition of P. chihuahuana at the species level. Contrary to other reports, the results from this study suggest that needles of the three studied species contain a much greater number and diversity of flavonoids than previously reported for species of Pinus.