Tambja is a genus of colorful sea slugs, dorid nudibranchs, shell-less marine gastropod mollusks in the family Polyceridae.MolluscaBase (2018). Tambja Burn, 1962. Accessed through: World Register of Marine Species on 2026-03-07.
Biology These nudibranchs feed on bryozoans. They have a radula which bears a rachidian tooth whose upper margin is either smooth or notched; the lateral tooth has two crowns, and the other teeth are so flat as to resemble plates.
Pre-rhinophoral Sensory Organs The most significant external feature of the genus Tambja is the ovular structure of "lateral slots" located between the rhinophores and the oral tentacles. In many species, they look a bit like the "cheekbones" of the animal, and many are coloured as if they have applied blush. In species like Tambja morosa and Tambja verconis they are very pronounced. Yet in other species, like Tambja dracomus and Tambja kava, they are far smaller and more subtle, or can even be obscured by the brim of the anterior mantle margin.
These ovular structures are lamellate upon close inspection, and sit over a horizontal slit in the slug's body that can dilate at will. Dissection led to the discovery that it is connected to the rhinophores internally, confirming that the purpose of these structures are sensory in nature.Willan, R.C. & Chang, Y.-W. [Yen-Wei]. (2017). Description of three new species of Tambja (Gastropoda, Nudibranchia, Polyceridae) from the western Pacific Ocean reveals morphological characters with taxonomic and phylogenetic significance for traditional Polyceridae and related 'phaneorobranch' nudibranchs. Basteria. 81 (1-3): 1-23.
All species of Tambja are considered to have these pre-rhinophoral sensory organs. The only species who are unconfirmed to possess them are species that are only known from a single observation or single preserved specimen. This makes pre-rhinophoral sensory organs the most defining external diagnostic feature of Tambja sea slugs, as neither Nembrotha, Martadoris, nor Tyrannodoris possess these lateral slots. The type species of Roboastra, Roboastra gracilis also does not possess them.
The only exceptions are Roboastra tentaculata and the several related, unnamed Roboastra species do. These animals however can be easily separated from Tambja sea slugs, as they possess the dorso-laterally grooved oral tentacles distinct to Roboastra. The presence of the lateral slots in addition to other very Tambja-like internal anatomyPola M., Cervera J.L., Gosliner T.M.; 2005. Four new species of Tambja Burn, 1962 (Nudibranchia: Polyceridae) from the Indo-Pacific. Journal of Molluscan Studies. 71(3): 257-267 . have lead some to insist they should be removed from genus Roboastra, yet they continue to remain therein on basis of former a sister-clade with R. gracilis.Pola, M.; Cervera, J.L.; Gosliner, T.M.; 2007. Phylogenetic relationships of Nembrothinae (Mollusca: Doridacea: Polyceridae) inferred from morphology and mitochondrial DNA. Molecular Phylogenetics and Evolution. 43, 726–742.Pola, M., Cervera, J.L., Gosliner, T.M., 2008. Description of the first Roboastra species (Nudibranchia, Polyceridae, Nembrothinae) from the Western Atlantic. Bulletin of Marine Science. 83: 391-399.
Species Species in the genus Tambja include:
Tambja abdere Farmer, 1978 Tambja affinis (Eliot, 1904) Tambja amitina (Bergh, 1905) - nomen dubium Tambja anayana Ortea, 1989 Tambja blacki Pola, Cervera & Gosliner, 2006 Tambja brasiliensis Pola, Padula, Gosliner & Cervera, 2014 Tambja caeruleocirrus Willan & Chang, 2017 Tambja capensis (Bergh, 1907) Tambja ceutae Garcia-Gomez & Ortea, 1988 Tambja crioula Pola, Padula, Gosliner & Cervera, 2014 Tambja dracomus Willan & Chang, 2017 Tambja diaphana (Bergh, 1877) - nomen dubium Tambja eliora (Er. Marcus & Ev. Marcus, 1967) Tambja fantasmalis Ortea & García-Gómez, 1986 Tambja gabrielae Pola, Cervera, & Gosliner, 2005 Tambja gratiosa (Bergh, 1890) Tambja haidari Pola, Cervera, & Gosliner, 2006 Tambja kava Pola, Padula, Gosliner & Cervera, 2014 Tambja marbellensis Schick & Cervera, 1998 Tambja morosa (Bergh, 1877) Tambja mullineri Farmer, 1978 Tambja olivaria Yonow, 1994 Tambja pulcherrima Willan & Chang, 2017 Tambja sagamiana (Baba, 1955) Tambja simplex Ortea & Moro, 1999 Tambja stegosauriformis Pola, Cervera, & Gosliner, 2005Pola P. M., Cervera J. L. & Gosliner T. M. (2005). "A new species of Tambja (Nudibranchia: Polyceridae: Nembrothinae)". Journal of the Marine Biological Association of the United Kingdom 85(4): 979-984. PDF. Tambja tenuilineata Miller & Haagh, 2005 Tambja verconis (Basedow & Hedley, 1905) - type species Tambja victoriae Pola, Cervera, & Gosliner, 2005 Tambja zulu Pola, Cervera, & Gosliner, 2005
Species brought into synonymy:
Tambja amakusana Baba,1987: Martadoris amakusanaWillan R.C. & Chang Y.-W. [Yen-Wei]. (2017). Description of three new species of Tambja (Gastropoda, Nudibranchia, Polyceridae) from the western Pacific Ocean reveals morphological characters with taxonomic and phylogenetic significance for traditional Polyceridae and related 'phaneorobranch' nudibranchs. Basteria. 81(1-3): 1-23. (Baba,1987)
Tambja divae (Er. Marcus, 1958): synonym of Martadoris divae (Er. Marcus, 1958) Tambja fusca Farmer,1978: synonym of Tambja abderePola M., Valles Y., Cervera J. L., Medina M. & Gosliner T. M. (2006). "Taxonomic status of Tambja abdere and T. fusca based on morphological and molecular evidence, with comments on the phylogeny of the subfamily Nembrothinae (Nudibranchia, Polyceridae)". Annales Zoologici Fenici 43: 52-64. PDF. Farmer, 1978 Tambja kushimotoensis Baba, 1987: synonym of Tambja morosa (Bergh, 1877) Tambja limaciformis (Eliot, 1908): synonym of Martadoris limaciformis (Eliot, 1908) Tambja mediterranea M. Domínguez, Pola & Ramón, 2015: synonym of Martadoris mediterranea (M. Domínguez, Pola & Ramón, 2015) Tambja oliva K. B. Meyer, 1977: synonym of Martadoris oliva (K. B. Meyer, 1977) Tambja tentaculata Pola, Cervera & Gosliner, 2005: synonym of Roboastra tentaculata (Pola, Cervera & Gosliner, 2005)
References