Cyerce ellingsonorum Moreno & Rico & Middlebrooks & Medrano & Valdés & Krug 2024, sp.nov.
Creators: name: Moreno, Karina
name: Rico, Diane M.
name: Middlebrooks, Michael
name: Medrano, Sabrina
name: Valdés, Ángel A.
name: Krug, Patrick J.
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Sacoglossa
Hermaeidae
Cyerce
Cyerce ellingsonorum

description: Cyerce ellingsonorum sp.nov.
(Figs 1–3, 5, 8C, 16)
ZooBank registration: lsid:zoobank.org:act: 960213E3-2A4A-4173-9413-55EE6D137788
Cyerce antillensis — Thompson 1977: 135–137, figs 22g, 30.
Type material
Holotype: Discovery Bay, Jamaica, March 2006, 3 mm preserved length (LACM 3841; isolate 06Jam09).
Additional material examined Jamaica, March 2006, one specimen preserved, isolate 06Jam05b.
Range
Jamaica (present study).
Description
External morphology: From Thompson (1977): brown in overall colour with scattered red specks. Rhinophores dark brown. Anal papilla prominent. Cerata paddle shaped, pale brown, with darker brown markings and white margins.
Internal morphology: Buccal mass <1 mm; buccal bulb larger than pharyngeal pouch. Radula of holotype specimen 2.4 mm long (LACM 3841), with six teeth on ascending limb and 10 teeth on descending limb (Fig. 16A). Teeth shallow, bent at an angle of 20°, tapering to pointed tip; 125 µm in length (Fig. 16A, B). Thompson (1977) reported a leading tooth 290 μm long for a 55-mm-long specimen from the type locality. A row of ~10 low, rectangular denticles along each cutting edge; denticles widest where tooth bends (≤ 6 μm wide), narrowing towards tip (Fig. 16B). Ascus with dense mass of ≥ 10 pre-radular teeth (Fig. 16C).
Penis with straight, cylindrical stylet with wide base, 65 µm long; triangular opening at pointed tip (Fig. 8C).
Ecology
Collected from the green alga Pe. dumetosus at the type locality; approximately five specimens per 400 g wet weight of algae were collected on two separate days. No other Cyerce specimens were obtained from collections of Udotea spp., Halimeda spp. or any other green alga made in Jamaica at the time the specimens of C. ellingsonorum were collected.
Etymology
Named in joint honour of Gary Ellingson and his son, Dr Ryan A. Ellingson, who co-collected the specimens analysed in the present study and helped P.J.K. to establish a molecular systematics research programme.
Remarks
Cyerce ellingsonorum was not recognized as a distinct species at the time of collection, and no photographs of live animals were taken, nor were photographs of living Cyerce specimens from Jamaica available to us. The best available description of the live animal is likely to be that of Cyerce specimens collected at the type locality of C. ellingsonorum by Thompson (1977). The specimens described by Thompson (1977) do not match C. antillensis well in external morphology, and the size and shape of the radular tooth are very different from C. antillensis but compatible with C. ellingsonorum. No specimens of C. antillensis were obtained from collections of H. opuntia made in Discovery Bay, Jamaica, when the specimens of C. ellingsonorum were collected. Based on molecular data, C. ellingsonorum was supported as distinct in all species delimitation analyses and might be endemic to Jamaica. In phylogenetic analyses, C. ellingsonorum was sister to three other C. antillensis complex members in a supported clade of four species. Notably, three of those four species are potential endemic taxa: C. ellingsonorum from Jamaica; C. willetteorum from Great Stirrup Cay, Bahamas; and C. browneveorum from the Florida Keys, USA. Only C. nicholasi had a widespread range among members of this clade. At least two of the four species are lecithotrophic (Table 5). If all four species inherited lecithotrophy from a common ancestor, limited dispersal potential might have promoted species formation in this lineage by reducing the scale of gene flow and favouring local adaptation.
The radular teeth of C. ellingsonorum were more angled than those of any Caribbean species except C. antillensis and bore the widest rectangular denticles of any complex member; the denticles were up to twice as wide on the teeth of C. ellingsonorum as on the teeth of C. nicholasi, which had the most similar radular morphology. A straight penial stylet bearing a triangular pointed tip differentiated C. ellingsonorum from most C. antillensis complex members, which had stylets that either curved or had oval openings (Table 5).
description: Published as part of Moreno, Karina, Rico, Diane M., Middlebrooks, Michael, Medrano, Sabrina, Valdés, Ángel A. & Krug, Patrick J., 2024, A cryptic radiation of Caribbean sea slugs revealed by integrative analysis: Cyerce ' antillensis' (Sacoglossa: Caliphyllidae) is six distinct species, pp. 940-979 in Zoological Journal of the Linnean Society 200 (4) on pages 967-968, DOI: 10.1093/zoolinnean/zlad111, http://zenodo.org/record/11240925