Avelona yvesi Gérard & Marchán, 2025

Gérard, Sylvain, Navarro, Alejandro Martínez, Decaëns, Thibaud, Hedde, Mickaël & Marchán, Daniel Fernández, 2025, Not the brightest earthworm in the genus: two non-bioluminescent Avelona (Lumbricidae, Crassiclitellata) with description of a new species, Zootaxa 5589 (1), pp. 270-281 : 273-277

Avelona yvesi Gérard & Marchán sp. nov.

urn:lsid:zoobank.org:act:76ABC2DB-AFF8-4F25-93DB-556B09AC3CF1

Type material. Holotype. France Adult; Bourgogne-Franche-Comté, Jura, Courbouzon; latitude/longitude: 46.660 / 5.527; elevation: 259 m asl; 11-April-2023; S. Gérard, J. Goussopoulos leg.; Sample ID: SG-0087 ; deposited at MNHN.

Paratypes. France 14 adult specimens, 5 subadult specimens; same data as holotype (19 specimens); Sample ID: SG-0089, SG-0090, SG-0091, SG-0092, SG-0093, SG-0094, SG-0095, SG-0096, SG-0097, SG-0098, SG-0099¸ SG-0100¸ SG-0101, SG-0102, SG-0103, SG-0104, SG-0105, SG-0106, SG-0107; deposited at Eco & Sols .

Etymology. The species is dedicated to Yves Gérard, the father of the first author of this work. Y. Gérard has always worked as a volunteer in highlighting and protecting biodiversity in Northeastern France through various nonprofit organizations (SHNM: Société d’Histoire naturelle de la Moselle and CPEPESC: Commission de protection des eaux, du patrimoine, de l’environnement, du sous-sol et des chiroptères). He battled against Amyotrophic lateral sclerosis and we want to pay tribute to him with the description of this species.

Description. External morphology ( Fig. 3 ). Pigmentation absent, except for a few faint mid-segment pigmentary dots in the first segments. Beige with a whitish clitellum after ethanol fixation ( Fig. 3A ). Average length: 3.73 cm (3–4.4 cm, holotype: 4.3 cm). Average weight: 0.19 g (0.15–0.25 g, holotype: 0.22 g). Average number of segments: 136 (131–140, holotype: 135). Setae closely paired, postclitellar setal formula aa: ab: bc: cd: dd = 9:1:5:1:20. On fixed specimens, the tail ends abruptly, as if it was cut ( Fig. 3B ). Prostomium epilobous, open. Longitudinal furrows in the first two segments. First dorsal pore in intersegment 3/4 (4/5). Nephridial pores aligned in area B (i.e., between setae b and c), at 1/2 ab from b. Spermathecal pores at intersegmental furrows 9/10–10/ 11 in c. Male pores in 15, surrounded by a strongly developed porophore extending over 14 and 16. Female pores in 14. Genital papillae in 9, 12, 13, 17 (strongly developed and consistent), (23, 26, 29) 30 (35, 36), in ab. Clitellum saddle-shaped in 28–35. Tubercula pubertatis in 32-1/n 35.

Internal anatomy. Septa 5/6–9/10 thickened. Lateral hearts in 6–11. Calciferous glands in 10–14, dilated in 10. Crop in 15–16, gizzard in 17–18. Typhlosole starts pinnate and becomes bifid around 24. Male sexual system holandric, testes and funnels (not enclosed in testes sacs, but with sperm present) located ventrally in 10 and 11. Two pairs of reniform seminal vesicles in 11 and 12. Ovaries and female funnels in 13, ovarian receptacles (ovisacs) in 14. Two pairs of small globular spermathecae in 10 and 11 (intersegments 9/10, 10/11), simple. Nephridial bladders J-shaped ( Fig. 5 ).

Differential diagnosis. Avelona yvesi sp. nov. can be distinguished from the most similar species Avelona zicsii ( Bouché, 1972) comb. nov. by the position of the clitellum (28–35 vs. 26–34(1/3-35)) and tubercula pubertatis (32- 1/n 35 vs. 30-1/2 33) ( Fig. 3 , Fig. 4 , Fig. S1 , Table 1 ). COI uncorrected average pairwise distances and topology of multilocus molecular phylogenetic trees supports the status of Av. yvesi sp. nov. as independent from other morphologically related species.

Distribution and ecology. Avelona yvesi sp. nov. was found in the vicinities of the Jura Massif (near Lons-le-Saunier) ( Fig. 2 ) in a pasture ( Fig. 3G ).

Figures

FIGURE 1. Phylogenetic relationships of Avelona yvesi sp. nov., their closest relatives and other genera of Lumbricidae inferred by Maximum Likelihood analysis based on the concatenated sequence of COI, 16S, ND1, 28S and 12S.

FIGURE 2. Map displaying the known distribution of Avelona species (Av. yvesi sp. nov.: orange; Av. zicsii comb. nov.: light green; Av. ligra: blue). Data from Bouché (1972) and #Vers2022. Loire river is highlighted in light blue, Allier river is highlighted in light purple. French continental massifs are surrounded by a yellow dotted line.

FIGURE 3. Pictures of Avelona yvesi sp. nov. (paratypes). A, B, C: after fixation in absolute ethanol; D, E, F: alive specimens; G: Place were Avelona yvesi sp. nov. was found. Photographic credits: Nicolas Henon (A to F); Sylvain Gérard (G). Scale bars: 0.5 cm. Abbreviations: CL = Clitellum; TP = Tubercula pubertatis; Pap = Genital papillae; MP = Male pore; LF = Longitudinal furrows.

FIGURE 4. Pictures of other Avelona species. A to D: Avelona zicsii comb. nov. after ethanol fixation (A, B) and alive (C, D). E to I: Avelona ligra after ethanol fixation (E, F) and alive (G, H, I). J to K: Place were Avelona zicsii comb. nov. (J) and Avelona ligra (K) were found. Scale bars: 1 cm. Photographic credits: Sylvain Gérard (A to J); Axel Beringue (K).

FIGURE 5. Nephridial bladders from post-clitellar segments of the species a) Avelona yvesi sp. nov. b) Avelona zicsii comb. nov. and c) Avelona ligra.