The sea anemone Metapeachia tropica (Panikkar, 1938), which was described from Madras, India, and belongs in family Haloclavidae, has previously been recorded in the Republic of Singapore but without details of appearance and occurrence. We rediagnose Metapeachia and redescribe M. tropica to accommodate the specimens we studied from Singapore (35 individuals were collected and others were only observed in situ); we designate a neotype for the species. A specimen has a cream-colored column, a patterned oral disc, 16 tentacles, and a conchula. Specimens of another species of Haloclavidae occur rarely in some of the same places as M. tropica in Singapore; we describe it as Synpeachia temasek new genus, new species, based on 8 individuals we collected and others that were only observed in situ. An individual has a reddish-brown column, an oral disc that can be patterned like that of M. tropica, 20 tentacles, and a conchula. We infer S. temasek may range west at least as far as Pakistan. Specimens of both differ from the type specimens of the species described from Annam, Vietnam as Peachia mira Carlgren, 1943, which we have not found in Singapore. We provide a key to some members of the Haloclavidae that differentiates the new genus.

Namalycastis glasbyi Fernando & Rajasekaran, 2007 was originally described from the creek-lined coast north of Mumbai in western India. However, the original description includes some oddities that make species recognition problematic and may confuse future taxonomic evaluations of the genus. Moreover, the type material of the species has been lost and, therefore, this species is herein redescribed, a neotype is assigned, and the distinguishing morphological features are clearly illustrated. The species shares some features with two other Indian species: Namalycastis indica Southern, 1921 and the N. abiuma Müller in Grube, 1871 species group. However, N. glasbyi differs from N. indica in having comparatively smaller antennae, shorter posterior dorsal cirri, a higher count of notochaetae (maximum of three) in the mid and anterior body, and finely serrated blades in sub- and supra-neuroacicular falcigers in the anterior and mid-body. Further, sub-neuroacicular spinigers have finely serrated blades in all parapodia in N. glasbyi, as opposed to the coarsely serrated spinigers from antero-mid body parapodia of N. indica. Moreover, N. glasbyi differs from the N. abiuma species group in lacking coarsely serrated sub-neuroacicular spinigers in the parapodia of mid and posterior parts of the body and in possessing a tripartite pygidium. In addition to these morphological differences, the mitochondrial COI sequence (DNA barcode) of the neotype of Namalycastis glasbyi clearly distinguishes it from other Indian species.

Anelpistina nubigena, new species (Insecta: Zygentoma: Nicoletiidae) is described from the ecotourism center of Las Nubes, in the Selva Lacandona rainforest of Chiapas, Mexico. Sequencing of 16S rRNA of specimens collected from the area revealed that at least one additional sympatric species of Anelpistina inhabits this same locality.

Two new species of Anelpistina (Insecta: Zygentoma) are described. They are the first nicoletiid insects of the subfamily Cubacubaninae from the Yucatan Peninsula, México. Morphology and preliminary sequence data of the 16S rRNA support their relatedness to species from the State of Chiapas in southeastern México.

Botryllophilus kozloffi is described, based on females living in the branchial sac of the zooid of the compound ascidian Clavelina lepadiformis (Müller, 1776) collected at Roscoff, France. The new copepod belongs to subgroup 2 (leg armature formula pattern II) of female morphotype A (urosome 5-segmented) of the genus, and is primarily characterized by the following morphological features: 1) metasome (segmentation indistinct) large and inflated dorsally, anterior prosome strongly curved from left to right, and urosome long cylindrical; 2) on medial margin of mandibular coxa, 2 conical spines each associated with 1 small subconical spine anteroproximally; 3) right leg 1 exopod approximately trapezoidal, bearing 7 long spines (I–VII) on wide distal margin, its central distal portion bearing 4 spines (II–V) distinctly protruded; and 4) leg 5 short stout, directed posterolaterally.

Botryllophilus millari is described on the basis of females living in the compound ascidian Eudistoma caeruleum (Sluiter, 1898) collected in Madagascar. The new copepod provides the diagnostic morphological characters for subgroup 2 of female morphotype A (urosome 5-segmented) of the genus, but armature formula (setae and spines) for right and left legs 1–4 is assigned to the new formula pattern III; seven congeners of subgroup 2 have formula pattern II. The new species is also characterized by the following morphological features including the unique features for legs 1–5: 1) body fusiform, segmentation of metasome indistinct; 2) first to fourth pairs of legs placed obliquely from left side toward right side; 3) right leg 1 exopod modified trapezoidal (medial margin elongated), with 6 long spines on oblique distal margin; and 4) leg 5 short stout, directed anterolaterally. The new copepod is the fourth and last species of Botryllophilus described from the Humes collection in Madagascar (1967).

A new species of tardigrade (Eutardigrada: Isohypsibiidae) was discovered in moss in the Wuyi Mountains, Fujian Province, southeastern China. Doryphoribius mcinnesae, new species, belongs to the evelinae group because it has two macroplacoids and displays cuticular gibbosities. The surface of the body on the dorsal and lateral sides is sculptured with a reticular formation. The first macroplacoid is longer than the second one; lunules and cuticular bars on legs are absent. It differs from the other members of the group by having a different gibbosity configuration (X: 2-3-1-3-1-3-1-2-2-2) or cuticular sculpture. The paper includes a detailed comparison of the new species with other similar but different species.

Analyses of the mitochondrial cytochrome-b gene were used to determine levels of genetic differentiation and patterns of relationship among members of the Neotoma mexicana (Mexican woodrat) species group in Mesoamerica. Three well-supported clades were obtained that conform to the species N. ferruginea Tomes, 1862, N. mexicana Baird, 1855, and N. picta Goldman, 1904. Neotoma ferruginea is the senior name for the clade that contains samples from southern Mexico and Nuclear Central America previously identified as N. isthmica Goldman, 1904, or as subspecies of N. mexicana (chamula Goldman, 1909; vulcani Sanborn, 1935). The phylogeographic pattern observed within the N. mexicana species group resembles that reported for other vertebrates co-distributed in mountains to the west (Trans-Mexican Neovolcanic Belt, Oaxacan sierras) and east (highlands of Chiapas, Mexico, and Nuclear Central America) of the Isthmus of Tehuantepec.

Análisis filogenéticos del gen mitocondrial Citocromo b se utilizaron para determinar los niveles de diferenciación genética y los patrones de relaciones entre miembros del grupo de especies de Neotoma mexicana en Mesoamerica. Se obtuvieron tres clados bien soportandos que están conformados por las especies Neotoma ferruginea Tomes, 1862; N. mexicana Baird, 1855; y N. picta Goldman, 1904. Neotoma ferruginea es el nombre más antiguo para el clado que contiene muestras del sur de México y Centro América Nuclear que previamente fueron identificadas como N. isthmica Goldman, 1904, y una subespecie de N. mexicana (chamula Goldman, 1909; vulcani Sanborn, 1935). El patrón filogeográfico observado entre el grupo de especies de N. mexicana se asemeja al reportado para otros vertebrados co-distribuidos en las montañas del Oeste (Eje neovolcánico transversal, Sierras de Oaxaca) y el Este (tierras altas de Chiapas, México y Centro América Nuclear) del Itsmo de Tehuantepec.