Martiodrilus (Botaria) lavellei Decaëns & Bartz, 2024

Decaëns, Thibaud, Bartz, Marie Luise Carolina, Bartz, arolina, Feijoo-Martínez, Alexander, Goulpeau, Arnaud, Lapied, Emmanuel, Marchán, Daniel F., Maggia, Marie-Eugénie, Papuga, Guillaume & James, Samuel W., 2024, Earthworms (Oligochaeta, Clitellata) of the Mitaraka range (French Guiana): commented checklist with description of one genus and eighteen species new to science, Zoosystema 46 (9), pp. 196-244 : 206-209

Martiodrilus (Botaria) lavellei Decaëns & Bartz , n. sp.

( Fig. 7 )

urn:lsid:zoobank.org:act:AFE58CB8-CEE3-46FE-8576-0259AAF5E274

TYPE MATERIAL. — Holotype. French Guiana • Adult; Tumuc-Humac, Mitaraka Massif , tropical rainforest on DIADEMA project A trail, in the soil; 2°14’27”N, 54°27’15”W; 359 m a.s.l.; III.2015; T. Decaëns, E. Lapied leg.; BOLD Sample ID: EW-MI15-0105 ; MNHN.

ETYMOLOGY. — This species is named in honour of Patrick Lavelle, in acknowledgement to his contribution for the study of tropical earthworm ecology.

ECOLOGY. — This species is only known from the holotype specimen, which has been collected in the organo-mineral soil of a plateau forests ( Fig. 7D, E ).

DISTRIBUTION. — Martiodrilus (B.) lavellei Decaëns & Bartz , n. sp. is only known from the Mitaraka Massif.

DESCRIPTION

External morphology ( Fig. 7A, B )

Body shape cylindrical. Body pigmentation dorsally light brown, ventrally beige. Body length: 56 mm after ethanol fixation. Body mass: 0.19 g after ethanol fixation. Diameter: 3.4 mm in the preclitellar region, 4.2 mm in the clitellum, 2.5 mm in the postclitellar region. Number of segments: 131. Prostomium proepilobic. One pair of longitudinal grooves going anterior to posterior through segment I in line of nephridial pores. Setae closely paired, ab beginning in II, cd in III. Setal arrangement aa:ab:bc:cd:dd = 8:1:10:2:34. Clitellum in (dorsal XV) XVI-XXV, saddle-shaped ( Fig. 7A ). Genital markings in V-XXIII, intraclitellar in XV-XXV (ab position). Tubercula pubertatis linear in 1/4 XX-½ XXV ( Fig. 7B ). Male pores not recognised, and ovipores not visible. Spermathecal pores in 5/6, 6/7 and 7/8, near nephridial pore. Nephridial pores begining in III, in CD line.

Internal anatomy ( Fig. 7C )

Septa: membranous. Gizzard: muscular and well developed in VI, 1.80 × 2.30 mm (width × length). Calciferous glands: eight pairs, in VII-XIV with tubular composite structure. Esophagus-intestine transition in XVIII/XIX; intestine without caeca.Typhlosole abruptly begining in XXVI, structured as a long thin folded lamella occupying all the lumen. Hearts: five pairs, the two intestinal pairs well-developed in X-XI. Excretory apparatus holoic, nephridia with simple nephrostome. Testes sacs: semi-periesophageal in X and XI, enclosing basal part of hearts, calciferous glands and seminal vesicles. Seminal vesicles: two pairs in XI-XII, small lobulated occupying their segments only. Spermathecae: three pairs, VI, VII, VIII; ovoid elongated without diverticula.

REMARKS

Martiodrilus (B.) lavellei Decaëns & Bartz , n. sp. belongs to the subgenus Botaria because of the presence of three pairs of spermathecae. It differs from the majority of species in the subgenus by its clitellum beginning in XVI, a position which it shares only with the two Guyanese species Martiodrilus (Botaria) dewynteri Csuzdi & Pavlicek, 2011 and Martiodrilus (Botaria) helleri ( Michaelsen, 1918) . Although this needs to be confirmed on a larger number of specimens, the clitellum of M. (B.) lavellei Decaëns & Bartz , n. sp. seems less extended posteriously than in these two species, ending in XXV in the holotype specimen instead of XXVI to ½ XXVI. The position of tubercula pubertatis also differs among these species: 1/4 XX-½ XXV in M. (B.) lavellei Decaëns & Bartz , n. sp. instead of ½ XXI-½XXVI in M. (B.) dewynteri and XX-½ XXVI in M. (B.) helleri . Furthermore, M. (B.) lavellei Decaëns & Bartz , n. sp. is significantly smaller than M. (B.) helleri , and appears to have a lighter body pigmentation than M. (B.) dewynteri (light brown instead of brown-violet). Martiodrilus (B.) lavellei Decaëns & Bartz , n. sp. is clearly separated from other species of Martiodrilus from the Mitaraka Massif by its COI barcode ( Table 2 ). This species corresponds to OTU#080 in Maggia et al. (2021).

Figures

FIG. 7. — Martiodrilus (Botaria) lavellei Decaëns & Bartz n. sp.: A, external and lateral view of the anterior body (arrows indicate the clitellum position);B, external and ventral view of the anterior body (arrows indicate the position of the tubercula pubertatis); C, dorsal dissection showing anterior internal anatomy; D, habitat preferences;E, microhabitat preferences.All images from the holotype;CL, clitellum; DV, dorsal vessel;GZ, gizzard;IN, intestine;SP, spermathecae;SV, seminal vesicles; TP, tubercula pubertatis; N, total number of specimens in the dataset. Scale bars: 2.5 mm.