Dulichiidae Danaı 1849

Ariyama, Hiroyuki & Hoshino, Osamu, 2019, A new superfamilyı familyı genus and species of marine amphipodı Protodulichia scandensı from Japan (Crustacea: Amphipoda: Senticaudata: Corophiida), Journal of Natural History 53 (39), pp. 2467-2477 : 2468-2469

Protodulichioidea Ariyamaı superfam. nov.

[Japanese name: Bōnobori-yokoebi-jōkaı new]

Type family

Protodulichiidae Ariyamaı fam. nov.

Diagnosis

Body subcylindricalı all pereonitesı pleonites and urosomites free. Head trianguları rostrum well developedı anteroventral margin strongly recessed; eyes largeı round. Antennae elongateı slender; antenna 1 peduncular articles 1ı 3 almost same lengthı shorter than article 2ı accessory flagellum short; antenna 2 longer than antenna 1ı peduncular articles 4ı 5 longı flagellum short. Mandibleı palp with 3 articlesı article 2 longestı article 3 symmetricalı bullet-shaped. Coxae medium-sizedı contiguous; gills present on coxae 2 – 6ı oostegites of female present on coxae 2 – 5. Gnathopod 1 subchelateı carpus longer than propodusı palm oblique. Male gnathopod 2 a little enlargedı subchelate; carpus shorter than propodusı propodus dilatedı palm oblique. Female gnathopod 2 smaller than that of maleı subchelate; carpus slightly shorter than propodusı palm oblique. Pereopods 3ı 4 short; bases slenderı glandular. Pereopods 5ı 6 short; bases expanded. Pereopod 7 greatly elongateı basis weakly expanded. Uropods biramousı uropods 1ı 2 slenderı uropod 3 short; peduncles of uropods 2ı 3 shorter than both rami; outer rami of all uropods shorter than inner ramiı both rami with robust setae. Telson dorsoventrally thickenedı entireı ovateı longer than broad.

Remarks

Myers and Lowry (2003) analysed the corophiidean genera using 41 morphological characters. Protodulichioidea superfam. nov. is different from the genera listed in Appendix 1 of this paper in at least six characters and does not closely resemble any generaı families or superfamilies listed. In particuları character 36 (setae on the uropod 3 outer ramus) differs significantly. The outer ramus of the new superfamily bears 0 – 1 dorsal and 1 apical robust setae (see ‘Description’ and ‘Variation’)ı and such a setation does not correspond with any types given by them.

This new superfamily belongs to the parvorder Caprellida Leach 1814 because length of the antenna 1 article 3 is more than half of the article 2 ( Myers and Lowry 2003). The parvorder consists of seven superfamilies. Protodulichioidea superfam. nov.ı howeverı can be distinguished from the superfamily Aetiopedesoidea Myers and Lowryı 2003 by the glandular bases of pereopods 3ı 4; from the superfamilies Caprelloidea Leach 1814 and Microprotopoidea Myers and Lowryı 2003 by the biramous uropod 3; from the superfamily Isaeoidea Danaı 1852 by the not subchelate pereopods 5 – 7; from the superfamily Neomegamphopoidea Myersı 1981 by the not enlarged gnathopod 1 and the not expanded coxa of male gnathopod 1; from the superfamily Photoidea Boeckı 1871 by the short peduncle of uropod 3; and from the superfamily Rakirooidea Myers and Lowryı 2003 by the separated urosomites 2ı 3.

The most conspicuous character of Protodulichioidea superfam. nov. is a triangular head. This character and the mast-building behaviour (see ‘Ecology’) are shared only with the family Dulichiidae Danaı 1849 among all the families in the infraorder Corophiida . Although Dulichiidae differs from this new superfamily in 12 characters out of 41 [for exampleı the pereonites 6ı 7 fusedı the urosomite 1 extremely elongateı and the uropod 3 absent in Dulichiidae ( Laubitz 1977) ]; this suggests that there may be a relationship between Protodulichioidea and Dulichiidae . Regarding Dulichiidaeı Laubitz (1979) estimated the suborder Caprellidea (in the traditional sense) is derived from an ancestral form close to Dulichiidae . Howeverı Ito et al. (2008) stated that the 18S rRNA gene sequence data did not support a close phylogenetic relationship between them. The relationship between Protodulichioidea and Dulichiidae is also expected to be examined by molecular analysis.

Included family

This superfamily contains only one familyı Protodulichiidae fam. nov.