Hymenodoridae, Lunina & Kulagin & Vereshchaka, 2024

Lunina, Anastasiia, Kulagin, Dmitry & Vereshchaka, Alexander, 2024, The taxonomic status of Hymenodora (Crustacea: Oplophoroidea): morphological and molecular analyses suggest a new family and an undescribed diversity deep in the sea, Zoological Journal of the Linnean Society (Zool. J. Linn. Soc.) 200 (2), pp. 336-351 : 349

Key to species and species complexes of Hymenodoridae

(For the generic diagnoses of Hymenodora and Sclerodora , see Vereshchaka et al. 2022.)

1. Rostral teeth subuliform, integument firm ................... Sclerodora crosnieri Vereshchaka, Kulagin & Lunina, 2021 ( Sclerodora Vereshchaka, Kulagin & Lunina, 2021)

- Rostral teeth ordinary, subtriangular, integument membranous ............................................... 2 ( Hymenodora G.O. Sars, 1877 )

2. Telson terminating in elongated, distally rounded spatulate endpiece laterally armed with spines ( Fig. 2C ) ............................. ........................................................................................................................................................ 3 (‘ Hymenodora acanthitelsonis ’ clade)

- Telson distally truncated ............................................................................................................................................................................. 4

3. Ocular peduncle nearly as long as broad at base; cornea reduced, unpigmented ................ Hymenodora chacei Wasmer, 2022

- Ocular peduncle nearly twice as long as broad at base; cornea faceted, pigmented .......................................................................... ................................................................................................................................................. Hymenodora acanthitelsonis Wasmer, 1972

4. Additional lateral sulcus on carapace present ( Fig. 2A ) .......................................................................................................................... ................................................................................ ‘ Hymenodora glacialis ’ complex ( H. glacialis A, H. glacialis B and H. glacialis C)

- Additional lateral sulcus on carapace absent ........................................................................................................................................... 5

5. Rostrum overreaching distal end of antennular peduncle .................................................... Hymenodora frontalis Rathbun, 1902

- Rostrum not reaching distal end of antennular peduncle ....................................................................................................................... ............................................................................................................... ‘ Hymenodora gracilis ’ complex ( H. gracilis A and H. gracilis B)

Figures

Figure 2. Morphological characters of Hymenodora (scheme).A, lateral carapace view of Hymenodora glacialis. B, second maxilliped of Hymenodora gracilis. C, posterior part of the telson of Hymenodora acanthitelsonis (after Wasmer 1972).