Cryptonome Borda, Kudenov, Bienhold & Rouse, 2012

Cryptonome Borda, Kudenov, Bienhold & Rouse, 2012 View in CoL , emended

Type species. Cryptonome conclava Borda, Kudenov, Bienhold & Rouse, 2012 View in CoL , by original designation.

Diagnosis (emended, Barroso et al. 2018, modifications in bold type). Amphinominae with caruncle reduced, cushion-shaped or tapered, as long as, or shorter than median antenna. Chaetiger 1 incomplete dorsally. Parapodia biramous; notopodia conical often with collars, neuropodia mound-shaped on swollen lobes. Dorsal cirri cirriform, smooth or pseudarticulate. Ventral cirri conical to subulate, tapered, usually smooth. Notochaetae include harpoons, sometimes with two series of denticles (barbed), delicate spurred to bifurcate capillaries, and bifurcate chaetae; notopodial hooks absent. Neurochaetae include bifurcate chaetae, with long basally swollen prongs, and delicately spurred capillaries. Noto- and neuroaciculae hastate. Branchiae dichotomously branching tufts from chaetiger 3, continued almost to last chaetiger. Anus dorsal, in last 1–2 chaetigers; anal cirri unpaired, lobate.

Composition. Borda et al. (2012: 318) included C. turcica ( Çinar, 2008) but overlooked the fact that it has pseudarticulate cirri, and this explains the main emendation; the other ones are after recognizing it as belonging in Amphinominae Savigny in Lamarck, 1818.As a consequence, subfamily features were deleted from earlier diagnosis. Cryptonome currently includes four species (Read & Fauchald 2023): C. barbada Barroso, Kudenov, Halanych, Saeedi, Sumida & Bernardino, 2018 ; C. conclava Borda, Kudenov, Bienhold & Rouse, 2012 ; C. parvecarunculata ( Horst, 1912) ; and C. turcica ( Çinar, 2008) . However, after the diagnosis has been redefined, other species should be integrated into Cryptonome and are herein newly combined and transferred from Pareurythoe Gustafson, 1930 . For example, Pareurythoe americana Hartman, 1951 , or Hipponoe elongata Treadwell, 1931 , briefly characterized below. These two species are newly combined and included in the key below. On the other hand, a key to the genera of Amphinominae is available elsewhere ( Bleeker et al. 2023).

Remarks. Among Amphinomin genera, Cryptonome and Pareurythoe have similar morphologies; both have chaetiger 1 dorsally incomplete, a small caruncle, and branchiae along most body chaetigers. However, there are two differences separating them, in Cryptonome the median antenna is as long as, or longer than caruncle, and first branchiae have many filaments, whereas in Pareurythoe the median antenna is shorter than caruncle, and first branchiae have a few filaments. Another relevant difference is in their ecology, because most Cryptonome species have been found in decaying wood, whereas Pareurythoe species are recorded from sediments.

Key to species of Cryptonome Borda, Kudenov, Bienhold & Rouse, 2012 View in CoL

(modified after Borda et al. 2012)

1 Parapodial cirri smooth, non-pseudoarticulate; median antenna longer than laterals................................. 2

– Parapodial cirri pseudoarticulate, especially along anterior region; size of median antenna variable..................... 5

2(1) Caruncle small, cushion-shaped.......................................................................... 3

– Caruncle elongate, tapered first branchiae with about 10 filaments; median antennae minute, shorter than laterals.................................................................. C. elongata ( Treadwell, 1931) View in CoL n. comb. Caribbean Sea

3(2) First branchiae with about 10 filaments; harpoon notochaetae with two series of denticles (barbed)......................................... C. barbada Barroso, Kudenov, Halanych, Saeedi, Sumida & Bernardino, 2018 View in CoL Southwestern Atlantic

– First branchiae with about 20 filaments; harpoon notochaetae with a single series of denticles......................... 4

4(3) Branchiae of anterior segments very long, covering dorsum.......................................................................................... C. conclava Borda, Kudenov, Bienhold & Rouse, 2012 View in CoL Eastern Mediterranean

– Branchiae of anterior segments short, not covering dorsum........ C. americana ( Hartman, 1951) View in CoL n. comb. Gulf of Mexico

5(1) Median antenna as long as laterals; anterior eyes slightly larger than posterior ones................................................................................................ C. turcica ( Çinar, 2008) View in CoL Eastern Mediterranean

– Median antenna markedly longer than laterals, reaching anterior prostomial margin................................. 6

6(5) Eyes minute, of similar size (deep water form)........................... C. parvecarunculata ( Horst, 1912) View in CoL Malaysia

– Eyes large, anterior eyes larger than posterior ones (shallow water form).............. C. beatrizae View in CoL n. sp. Western Mexico

Remarks. African records of C. parvecarunculata ( Horst, 1912) are questionable. The record from Western Africa ( Augener 1918: 90, Pl. 2, Fig. 3 View FIGURE 3 , Pl. 3, Figs 37, 38) is probably after an eyeless specimen, whereas the one for South Africa ( Day 1967: 128, Fig. 3.2i–l View FIGURE 3 ) has a shorter median antenna, not reaching anterior prostomial margin. They probably belong to different, undescribed species.