Bhawatsonia nenoae, Cruz-Gómez, 2021

Cruz-Gómez, Christopher, 2021, A new genus and seven new species of chrysopetalids (Annelida, Chrysopetalidae) from the Tropical Eastern Pacific, Zootaxa 5068 (1), pp. 1-59 : 36

Bhawatsonia nenoae n. sp.

Figs 18 , 26

LSID: urn:lsid:zoobank.org:pub:F0D7412B-5968-4459-9BA4-F1A314BA8EC7

Bhawania sp. 2 .— Cruz-Gómez et al. 2021: 180, Fig. 5D (key of chrysopetalids from Tropical America).

Type locality: Hornos Beach , Acapulco, Guerrero, México .

Type material. Holotype: ECOSUR-269 , Hornos Beach , 16°51´6”N, 99°54´1”W, Acapulco, Guerrero, México, southern Mexican Pacific, on Spondylus sp. April 19, 2008, coll. SSV & LCP.

Description. Based on the holotype: complete with up to 300 segments. TL= 38 mm, TW= 2.3 mm. Body stiffed, long, narrowed posteriorly( Fig. 18A ). Body pale violet to brown, dorsal and ventral cirri bases darker. Paleae fan bright maroon to golden, non-imbricated dorsally.

Prostomium completely retracted among the first six, caused by the fixation method. Antennae, prostomium, nuchal organ not seen; eyes barely noticed. Palps long, cylindrical, visible only in ventral view. Mouth fold small, placed between segment 3 and 4. Pharynx eversible, not exposed and not detected by transparency.

Parapodium from segment 142, notochaetae in three main groups ( Fig. 18B ). Notochaetae: lateral group inserted below notaciculum, 2 paleae, very slender and symmetrical, with 2 internal ribs ( Fig. 18C ); subunit 1, 1 palea, broader and symmetrical, with 12–14 internal ribs ( Fig. 18D ). Main group, 14–16 paleae, broader and symmetrical, with 18–20 internal ribs ( Fig. 18E ). Median group, 2 paleae, curved, shorter and asymmetrical; the distal-most palea with 13 internal ribs and, the proximal-most and smallest with 13 internal ribs ( Fig. 18F–G ).

Neuropodium conical, smaller than the notopodium. Neurochaetae: unit 1, 2 superior spinigers, blades straight and long, 12–13 times longer than wide ( Fig. 18H ). Unit 2, 8 falcigers, blades straight and short, 2–3 times longer as wide ( Fig. 18I–J ). Unit 3, 6 falcigers, blades straight and short, 2–3 times longer than wide ( Fig. 18K–L ). Unit 4, 2 falcigers, blades straight and medium-sized, 4–5 times longer than wide ( Fig. 18M ). Blades bidentate, bended distally. Pygidium conical, with two anal cirri ( Fig. 18N ). Oocytes not seen.

Habitat. Subtidal. The specimen examined was collected as epibiont of bivalves.

Distribution. Only known from Acapulco, Guerrero ( Fig. 26 ).

Remarks. B. nenoae n. sp. resembles B. purpurea n. comb. in having slender main paleae and broad median paleae, but they can be differentiated using the form of main paleae and the features present in the subunit 1 paleae (see B. purpurea n. comb. remarks). Moreover, specimens of B. nenoae n. sp. can be easily recognized by possessing the proximal-most median palea drop-like shape.

Etymology. The species is named after the author’s sister, Jaemy Cruz-Gómez, aka “Neno”, in recognition of her support and company during our childhood and even now regardless of the distance. The epithet is a noun in the genitive case ( ICZN 1999, Art. 31.1.2).

Figures

FIGURE 5. Paleanotus karlyae n. sp., holotype (ECOSUR-258). A) Complete fragmented body. B) Drawing of prostomium, dorsal view. C) Drawing of pygidium, ventral view. D) Parapodium from segment 23. E) Lateral paleae. F) Subunit 1. G) Main palea. H) Apex of G. I–J) Median paleae. K) Unit 1. L) Unit 2. M) Unit 3. N) Unit 4. Scales: 10 µm (KLMN), 20 µm (CEFH), 50 µm (IJ), 100 µm (B), 200 µm (D), 500 µm (A).

FIGURE 18. Bhawatsonia nenoae n. sp., holotype (ECOSUR-269). A) Complete body. B) Parapodium from segment 142. C) Lateral palea. D) Subunit 1. E) Main palea. F–G) Median paleae. H) Unit 1. I) Unit 2. J–L) Unit 3. M) Unit 4. N) Drawing of pygidium, ventral view. Scales: 20 µm (CDHIJKLM), 50 µm (EFGN), 200 µm (B), 1 mm (A).

FIGURE 26. Previous and new records of chrysopetalids in the Tropical Eastern Pacific. Empty symbols indicate historic records.