A new species of the alpheid shrimp genus Salmoneus Holthuis, 1955, probably an obligate associate of ghost shrimp burrows, is described based on material from Oman (type locality: Darsait near Muscat), Iran and the Philippines. Salmoneus durisi sp. nov. is characterised principally by both chelipeds enlarged, robust, with ventral and dorsal margins of chelae carrying long fine setae, and with minor chela fingers armed with a few large teeth on cutting edges. All specimens of Salmoneus durisi sp. nov. were collected either directly from burrows of larger decapod crustaceans with the aid of a suction pump, or by exposing burrows dug under large subtidal rocks. The Iranian specimen was found together with its presumed host, Neocallichirus calmani (Nobili, 1904). Two additional specimens from Indonesia and the Solomon Islands are tentatively assigned to S. cf. durisi sp. nov., awaiting further studies.

PANGLAO 2004

The present study is based on material collected in the intertidal and shallow subtidal areas of two Islands in the Persian Gulf, Abu-Musa and Larak. The new species, Synalpheus pentaspinosus n. sp., is closely related to S. quinquedens Tattersall, 1921. These two species share a very characteristic, sixth pleonite armed posteriorly with five stout sharp teeth, a feature unique within the genus. The color of ovaries or freshly laid eggs, red-orange in S. pentaspinosus n. sp. vs. green in S. quinquedens, is the most obvious character, by which the new species may be distinguished from S. quinquedens in the field. In addition, the two species can be separated by two characters on the dactylus of the minor cheliped. In the new species, the dactylus is furnished with two prominent rows of setae, one dorsally and one mesially, and has a small concavity on the cutting edge, contrasting to only one mesial row of setae and no obvious concavity in S. quinquedens.

ATIMO VATAE

The present study focuses on shrimps belonging to the genus Lysmata Risso, 1816, collected from Madagascar during the Atimo Vatae expedition carried out in 2010. Lysmata malagasy sp. nov. is a new species belonging to the clade named “long accessory ramous” or “cosmopolitan” in previous phylogenetic studies. The new species can be distinguished from the only two other representatives of this group in the Indo-west Pacific, L. ternatensis De Man, 1902, and L. trisetacea (Heller, 1861), by the accessory ramus of the lateral antennular flagellum consisting of four elongated articles. Lysmata lipkei Okuno & Fiedler, 2010 is reported here from Madagascar with a remarkable extension of its known range after its original description from Japan. This species has also been reported from Singapore and, as alien species, from Brazil. Lastly, L. kuekenthali De Man, 1902 known from numerous localities in the Indo-West Pacific biogeographic area, is reported for the first time from Madagascar. Results of the present morphological and molecular analyses suggest that L. hochi Baeza & Anker, 2008 from the Caribbean Sea is a synonym of the Indo-West Pacific L. kuekenthali, and thus the latter species is alien in the western Atlantic.

ATIMO VATAE

The deep-water alpheid shrimp Batella praecipua De Grave, 2004 was originally described based on two incomplete specimens, both with their first chelipeds missing, collected at 400–440 m off New Caledonia. During the recent KANADEEP 1 expedition in the Coral Sea in 2017, the first complete specimen of B. praecipua was collected at a depth of 370–380 m. The morphology of this specimen is presented in detail, with emphasis on the highly diagnostic chelipeds, which are described and illustrated for the first time. A slight intraspecific variation of B. praecipua is reported and a DNA barcode (CO1) is provided for this species. The main differences between the three presently known species of Batella Holthuis, 1955 are discussed.

KANADEEP

The alpheid snapping shrimp genus Synalpheus Spence Bate, 1888, is a prominent component of arthropod diversity found in coral reefs. Notably, Synalpheus is the only genus of marine organisms known to exhibit eusocial behavior. Although eusociality has evolved at least four times independently in Synalpheus, all described eusocial species are from the West Atlantic, with only a single study documenting possibly eusocial species from Indonesia. In 2008, during an expedition to Madagascar organized by the Florida Museum of Natural History (FLMNH), a diverse array of sponge-dwelling species was collected, including two species of Synalpheus exhibiting colonial behavior. Through detailed examination of these specimens, we have confirmed that these two species are eusocial and represent new eusocial species of Synalpheus outside of the West Atlantic. Consequently, we provide the first official documentation of eusocial species from the Western Indian Ocean and present their taxonomic descriptions and their phylogenetic relationships with other species of the genus in this study.

MADIBENTHOS

The present study deals with the intricate phylogenetic relationships within an important clade of the caridean shrimp family Alpheidae, which includes the genera Salmoneus, Deioneus, and Triacanthoneus. Using molecular data from four genes (16S, 18S, COI, and H3), we herein provide the most comprehensive phylogenetic hypothesis for this alpheid clade, with 161 terminals representing 117 ESUs, i.e. genetically distinct species. Our analysis reveals four well-supported larger Clades, as well as 25 smaller clades, corresponding to species groups or species complexes. The results also show that the symbiotic lifestyle evolved multiple times within this clade, in some instances promoting convergent evolution. Ancestral character state analysis unveils extreme plasticity and independent shifts in the minor cheliped types. Furthermore, the impact of different lifestyles on the evolution of each minor cheliped type is discussed. Finally, we address the resulting paraphyly of Salmoneus and the intergeneric relationships between Salmoneus, Deioneus and Triacanthoneus.

KARUBENTHOS 2012, KAVIENG 2014, KOUMAC 2.3, MADIBENTHOS, PAPUA NIUGINI

Batellopsis paula gen. et sp. nov., a new hexactinellid-associated alpheid shrimp, is described based on a single specimen collected at a depth of 477–503 m north of Île des Pins, New Caledonia. Batellopsis gen. nov. is part of a clade of four genera all containing hexactinellid-associated species, for which a molecular phylogeny is presented. The evolution of several morphological characters, including orbital teeth, a bulge- fossa system on the fingers of the first pereiopod chela, and groups of microserrulate setae on the second pereiopod chela, is discussed in light of phylogenetic results.

EXBODI, KANACONO, KARUBAR, KOUMAC 2.1, MADIBENTHOS, TAIWAN 2002