Trypanedenta, IMAJIMA & HARTMAN, 1964

TRYPANEDENTA IMAJIMA & HARTMAN, 1964 View in CoL ;

FIGS 6E – I View Figure 6 , 8 View Figure 8 , 9 View Figure 9

Trypanosyllis (Trypanedenta) Imajima & Hartman : 125.

Trypanosyllis Claparede, 1864 (partim).

Type species: Trypanosyllis gemmipara Johnson, 1901 .

Diagnosis

Body variable in size, from 7 mm to more than 80 mm in length, and from 1 mm to 5 mm wide, with uniform yellowish coloration ( Figs 6E, G View Figure 6 ). Unidentate or bidentate chaetae, without serration in margin or with a few, minute spines ( Fig. 6F, I View Figure 6 ). Reproduction by clusters of several simultaneous tetraglene stolons ( Fig. 6G, H View Figure 6 ).

Remarks

Trypanedenta View in CoL was considered a subgenus of Trypanosyllis View in CoL , because of the lack of a middorsal tooth in the pharynx ( Imajima & Hartman, 1964). Our study concluded that Trypanedenta Imajima & Hartman, 1964 View in CoL should be raised to genus level, although the synapomorphies for the group require a re-evaluation of pharyngeal teeth during ontogeny (San Martın, 2003). Indeed, the type of reproduction, which differs from that in the other genera analysed, seems to be one of the most important features to differentiate this genus from the remaining genera. Both species included in the genus, Trypanedenta gemmipara View in CoL comb. nov. and Trypanedenta gigantea View in CoL comb. nov., present more than one stolon during their reproductive stages. Trypanedenta gemmipara View in CoL comb. nov. develops a cluster of stolons ( Johnson, 1901; Imajima & Hartman, 1964; Imajima, 1966), whereas Trypanedenta gigantea View in CoL comb. nov. forms a chain of stolons (first report, this paper; Fig. 6G View Figure 6 ). Another character that seems to be important for the diagnosis of the genus is the presence of chaetae with just a few small spines on the margin ( Trypanedenta gigantea View in CoL comb. nov.) or none ( Trypanedenta gemmipara View in CoL comb. nov.) ( Figs 6F, I View Figure 6 , 8E – F View Figure 8 , 9F – H View Figure 9 ). Further molecular studies are required to assess if other species currently included within Trypanosyllis View in CoL , presenting similar chaetae and more than one stolon during their reproductive stage, actually belong to Trypanedenta View in CoL . That may be the case for Trypanosyllis ingens Johnson, 1902 View in CoL , Trypanosyllis sanmartini Cinar, 2007 View in CoL , and Trypanosyllis auranticus Nogueira & Fukuda, 2008 ( Johnson, 1902; Cinar, 2007; Nogueira & Fukuda, 2008). In addition, the budding of numerous simultaneous stolons has also been observed in Trypanobia asterobia Okada, 1933 View in CoL , but the relationship between the recently resurrected genus Trypanobia Imajima & Hartman, 1964 View in CoL (Aguado et al., 2015) and Trypanedenta View in CoL needs further study.

Distribution

Cosmopolitan.

TRYPANEDENTA GEMMIPARA ( JOHNSON, 1901) View in CoL