Ormyrus labotus Walker (Hymenoptera: Ormyridae): another generalist that should not be a generalist is not a generalist

Several recent reappraisals of supposed generalist parasite species have revealed hidden complexes of species, each with considerably narrower host ranges. Parasitic wasps that attack gall-forming insects on plants have life history strategies that are thought to promote specialization, and though many species are indeed highly specialized, others have been described as generalist parasites. Ormyrus labotus Walker (Hymenoptera: Ormyridae) is one such apparent generalist, with rearing records spanning more than 65 host galls associated with a diverse set of oak tree species and plant tissues. We pair a molecular approach with morphology, host ecology, and phenological data from across a wide geographic sample to test the hypothesis that this supposed generalist is actually a complex of several more specialized species, though we identify no single unifying axis of specialization. We find 16-18 putative species within the morphological species O. labotus, each reared from only 1-6 host gall types. We also find cryptic habitat specialists within two other named Ormyrus species. Our study suggests that caution should be applied when considering host ranges of parasitic insects described solely by morphological traits, particularly given their importance as biocontrol organisms and their role in biodiversity and evolutionary studies.

Discovery of a new Steinernema sp. (Rhabditida: Steinernematidae) with higher shelf life and better efficacy against red palm weevil under laboratory conditions

Entomopathogenic nematodes (EPN) are excellent bio-control agents for the management of insect pests of soil and cryptic habitat. One of the greatest challenges in the successful utilization of EPN is the poor shelf life of infective juveniles (IJs) under ambient temperature. The present study aimed to evaluate the survival and virulence of different EPN species for determining a superior one in the bio-suppression of red palm weevil (RPW). Among the five species of Steinernematids and two Heterorhabditid isolates evaluated, Steinernema sp. (S0804) sustained up to 13 months, with a desirable survival of 100 per cent during the first five months to about 64 per cent ten months after storage at ambient temperature. Virulence of Steinernema sp. (S0804) sustained up to ten months of storage, was confirmed using Galleria mellonella inoculation test. However, the viable IJs were observed only up to one month in both the Heterorhabditids and up to a period of four to six months of storage in all other Steinernematids. The Steinernema sp. (S0804) was also found to be efficacious against the grubs of RPW in filter paper bio-assay inducing 100 per cent larval mortality in 72 h when applied @ 200 IJs per grub and confirmed further by leaf petiole bioassay. The study thus revealed higher survival and virulence of Steinernema sp. (S0804) and also found to be a potential bio-control agent against RPW. To the best of our knowledge, this is the first EPN isolate reported, which could survive for more than one year at ambient temperature without any additives.

A new species of the flower bug genus Orius Wolff (Hemiptera: Anthocoridae) cryptically inhabiting Hibiscus tiliaceus L. (Malvaceae)

A new species of the anthocorid genus Orius Wolff (subgenus Heterorius Wagner), O. (H.) hibiscus sp. n., is described, based on specimens recently found from the coastal area of Okinawa Island, Ryukyus, Japan. This new species, evidently most related to Orius (Heterorius) strigicollis (Poppius), was found to prefer cryptic habitat, or bract and flower bud of Hibiscus tiliaceus (L.) (Malvaceae) planted at urbanized zones in Naha City. Diagnostic characters of the new species are described, comparing with those of other Japanese members of Heterorius, based on detailed observation using a SEM. An updated checklist and revised key are provided to aid in identification of all known Japanese Orius species.

Recent thecideide brachiopods from a submarine cave in the Department of Mayotte (France), northern Mozambique Channel

For the first time large numbers of thecideide brachiopods have been collected from the Mozambique Channel, more particularly from the western part of the Comorian Island of Mayotte (France). The moderately diverse brachiopod fauna is from a submarine cave situated on the second barrier reef encircling this island, with three different genera being found: Thecidellina, Ospreyella and Minutella. The last genus is represented by M. cf. minuta (Cooper, 1981), which was first discovered around Madagascar. Ospreyella is represented by a new species (O. mayottensis sp. nov.) as is Thecidellina, which is represented by T. leipnitzae sp. nov. This species is markedly distinct from T. europa Logan et al., 2015 from Europa Island in the southern Mozambique Channel (1,200 km south of Mayotte), providing an example of allopatric speciation in an isolated cryptic habitat.

Cryptic habitat use of white sharks in kelp forest revealed by animal-borne video

Traditional forms of marine wildlife research are often restricted to coarse telemetry or surface-based observations, limiting information on fine-scale behaviours such as predator–prey events and interactions with habitat features. We use contemporary animal-attached cameras with motion sensing dataloggers, to reveal novel behaviours by white sharks, Carcharodon carcharias , within areas of kelp forest in South Africa. All white sharks tagged in this study spent time adjacent to kelp forests, with several moving throughout densely kelp-covered areas, navigating through channels and pushing directly through stipes and fronds. We found that activity and turning rates significantly increased within kelp forest. Over 28 h of video data revealed that white shark encounters with Cape fur seals, Arctocephalus pusillus pusillus , occurred exclusively within kelp forests, with seals displaying predator evasion behaviour during those encounters. Uniquely, we reveal the use of kelp forest habitat by white sharks, previously assumed inaccessible to these large predators.

Habitat utilization by an intertidal isopod, Dynoides dentisinus Shen, 1929 (Isopoda, Sphaeromatidae)

Intertidal isopods use a variety of living or non-living objects as habitats, although only a few studies have been made on their ecological function and significance. In the present study, the habitat utilization by the sphaeromatid isopod, Dynoides dentisinus was recorded based on observations on intertidal rocky shores in the warm temperate zone of Japan during the period from 2014 to 2018. The adults of this species have a remarkable sexual dimorphism in the morphology of their armature: adult males possess an elongate pleonal process, like a large horn, on the dorsal side of the pleon and have large uropods. On the other hand, females do not have such a horn, and the uropods are small. Differences in habitat use were seen according to the stage in the life history of the species. Juveniles lived on, or amongst, algae and were sometimes associated with molluscs such as chitons, limpets and whelks. Adults inhabited the cryptic habitats such as gaps in algal holdfasts, oscula of demosponges, dead barnacle shells, cavities of dead corals, and crevices in sand rocks. Generally, a single adult male was present in each cryptic habitat, keeping head in down position, and one or more females cohabited inside with the male. These suggest that D. dentisinus has a biphasic life history; juveniles live and feed on algal cover or use the spaces between the ventral sides of the molluscs and the surfaces of the rocks as a refuge from desiccation. Adults breed in the cryptic habitats, forming a polygynous group.

Disentangling nematode-bacteria interactions using a modular soil model system and biochemical markers

Interactions between bacteria and nematode grazers are an important component of soil food webs yet, due to the cryptic habitat, they are almost exclusively investigated in artificial agar substrate. Transport, food choice and foraging experiments were performed in a modular microcosm system with the nematode Acrobeloides buetschlii and bacterial diets (Escherichia coli, Pseudomonas putida and Bacillus subtilis) in gamma-irradiated soil. Bacterial biomass was assessed by soil phospholipid fatty acids (PLFAs). Continuous random foraging of nematodes was affected by soil type. Food choice experiments revealed diet switch and time lag preference responses, suggesting that nematode population fluctuations are driven by multiple factors such as bacterial attractants, defence strategies or food quality. Application of PLFA markers revealed a strong nematode predation pressure, as biomass in P. putida declined by 50%, whereas no transport of bacteria through soil was indicated. Overall, semi-natural experimental systems are an essential prerequisite to gain a realistic picture in microbial-microfaunal interactions.

Satellite tracking reveals novel migratory patterns and the importance of seamounts for endangered South Pacific humpback whales

The humpback whale population of New Caledonia appears to display a novel migratory pattern characterized by multiple directions, long migratory paths and frequent pauses over seamounts and other shallow geographical features. Using satellite-monitored radio tags, we tracked 34 whales for between 5 and 110 days, travelling between 270 and 8540 km on their southward migration from a breeding ground in southern New Caledonia. Mean migration speed was 3.53±2.22 km h −1 , while movements within the breeding ground averaged 2.01±1.63 km h −1 . The tag data demonstrate that seamounts play an important role as offshore habitats for this species. Whales displayed an intensive use of oceanic seamounts both in the breeding season and on migration. Seamounts probably serve multiple and important roles as breeding locations, resting areas, navigational landmarks or even supplemental feeding grounds for this species, which can be viewed as a transient component of the seamount communities. Satellite telemetry suggests that seamounts represent an overlooked cryptic habitat for the species. The frequent use by humpback whales of such remote locations has important implications for conservation and management.

New records of Catenicella de Blainville, 1830 (Catenicellidae: Cheilostomata: Ascophora) in Rio de Janeiro State, Brazil

Although there are six species of Catenicellidae recorded in Brazil, the three Catenicella species described here are the first mention of the genus in the state of Rio de Janeiro, enlarging their distribution along the Brazilian coast. Previously, C. contei was recorded in Pernambuco and São Paulo, while C. elegans was recorded in the states of Alagoas and São Paulo. The recent identification of these species in the state of Rio de Janeiro suggests two possibilities: it is difficult to find them due to small size and cryptic habitat, and/or they represent introduced species.