Atatina albida Bartz & Decaëns, 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 : 223-225

Atatina albida Bartz & Decaëns , n. sp.

( Fig. 16 )

urn:lsid:zoobank.org:act:A7BC66DF-5196-4FC2-9D83-3029CDEF9D45

TYPE MATERIAL. — Holotype. French Guiana • Adult; Tumuc-Humac, Mitaraka Massif , slope forest on DIADEMA project D trail, in decaying trunk; 2°13’40”N, 54°27’14”W; 339 m a.s.l.; III.2015; T. Decaëns, E. Lapied leg.; BOLD Sample ID: EW-MI15-0271 ; MNHN.

Paratypes. French Guiana • 1 adult specimen; Tumuc-Humac, Mitaraka Massif, Heliconia forest near plateau forest at base camp; 2°13’50”N, 54°26’57”W; 351 m a.s.l.; III.2015; T. Decaëns, E. Lapied leg.; BOLD Sample ID: EW-MI15-0052 ; CEFE • 1 adult specimen; Tumuc-Humac, Mitaraka Massif , lowland forest on DIADEMA project C trail; 2°14’16”N, 54°26’56”W; 310 m a.s.l.; III.2015; T. Decaëns, E. Lapied leg.; BOLD Sample ID: EW-MI15-0226 ; CEFE • 1 adult specimen; Tumuc-Humac, Mitaraka Massif , lowland forest on DIADEMA project D trail; 2°13’58”N, 54°27’7”W; 318 m a.s.l.; III.2015; T. Decaëns, E. Lapied leg.; BOLD Sample ID: EW-MI15-0306 ; MNHN • 1 adult specimen; Tumuc-Humac, Mitaraka Massif , plateau forest at base camp; 2°14’2”N, 54°27’1”W; 331 m a.s.l.; III.2015; T. Decaëns, E. Lapied leg.; BOLD Sample ID: EW-MI15-0368 ; MNHN • 1 adult specimen; Tumuc-Humac, Mitaraka Massif , slope forest on DIADEMA project D trail; 2°13’40”N, 54°27’14”W; 339 m a.s.l.; III.2015; T. Decaëns, E. Lapied leg.; BOLD Sample ID: EW-MI15-0270 ; MNHN • 5 adult specimens; Tumuc-Humac, Mitaraka Massif , transition forest # 2 Sommet en Cloche Inselberg ; 2°13’59”N, 54°27’34”W; 395 m a.s.l.; III.2015; T. Decaëns, E. Lapied leg.; BOLD Sample ID: EW-MI15-0121 , EW-MI15-0122 , EW-MI15-0123 , EW-MI15-0124 , EW-MI15-0125 ; MNHN .

OTHER MATERIAL EXAMINED. — French Guiana • 1 juvenile specimen; Tumuc-Humac, Mitaraka Massif , transition forest # 2 Sommet en Cloche Inselberg ; 2°13’59”N, 54°27’34”W; 395 m a.s.l.; III.2015; T. Decaëns, E. Lapied leg. (1 specimens); BOLD Sample ID: EW-MI15-0126 ; MNHN .

ETYMOLOGY. — This species is named after its lack of pigmentation.

ECOLOGY. — Atatina albida Bartz & Decaëns , n. sp. has been found in a range of ecosystems including lowland, slope, plateau, transition and Heliconia forests ( Fig. 16D ). It has been observed in the organo-mineral soil (75% of specimens) and in decaying trunks (25% of specimens) ( Fig. 16G ).

DISTRIBUTION. — Atatina albida Bartz & Decaëns , n. sp. is only known from the Mitaraka Massif.

DESCRIPTION

External morphology ( Fig. 16A, B )

Body shape cylindrical. Body pigmentation absent. Body length: 25 mm in the holotype, 24 to 41 mm in the paratypes (average: 31.3 mm; n = 3), after ethanol fixation. Body mass: 0.07 mm after ethanol fixation in the holotype, 0.06 to 0.15 g in the paratypes (average: 0.11 g; n = 3). Diameter: 1.5 to 2.0 mm in the preclitellar region, 1.5 to 2.1 mm in the clitellum, 1.5 to 2.4 mm in the postclitellar region. Number of segments: 167 in the holotype, 119 to 299 in the paratypes (average: 194; n = 3). Prostomium proepilobic. One pair of longitudinal grooves passing through segments I-II in line of nephridial pores. Setae widely paired. Setal arrangement aa:ab:bc:cd:dd = 2:1:3:1:12. Clitellum in XV-XXIV, saddle-shaped ( Fig. 16A ). Genital markings observed in some specimens in VII to VIII (ab position). Tubercula pubertatis linear XVII-XXIV ( Fig. 16B ). Male pores, ovipores, and spermathecal pores not recognised. Nephridial pores begining in XIV in CD line.

Internal anatomy ( Fig. 16C )

Septa: slightly thickened in 6/7 to 9/10, otherwise membranous. Gizzard: muscular and well developed in VI, with an average size (width × length) of 1.30 × 1.03 mm. Calciferous glands: four pairs forming simple expansions of the esophageal walls in IX-XII, apparently of glandular structure but not isolated from the gut lumen by having a distinct connecting duct. Esophagus-intestine transition in XVIII. Typhlosole begining in XXII, small folded lamella. Hearts: last two intestinal pairs in IX and X. Excretory apparatus holoic.Testes: in XI; mid-ventral metandric. Seminal vesicles: one pair in XI, extending posteriously to XXXX-LX. Spermathecae: two pairs in VIII and IX.

REMARKS

Atatina albida Bartz & Decaëns , n. sp. differs from Atatina gatesi ( Righi & Ayres, 1978) and Atatina puba ( Righi, 1971) , the only other known species in the genus, in the position of the clitellum and tubercula pubertatis, as well as in the presence of two pairs of spemathecae instead of one in these two relatives ( Righi 1971; Righi et al. 1978). It shares with A. gatesi the presence of four pairs of calciferous glands, but their position is different (at IX-XII in A. albida Bartz & Decaëns , n. sp. vs. XI-XIV in A. gatesi ). It also shares with A. puba the presence of a single pair of seminal vesicles in XI. This species corresponds to OTU#074 in Maggia et al. (2021).

Figures

FIG. 16. — Atatina albida Bartz & Decaëns n. sp.: A, external and lateral view of the anterior body (arrows indicate the clitellum and tubercula pubertatis positions); B, dorsal dissection showing anterior internal anatomy; C, detailed view of the dorsal dissection showing the calciferous glands; D, habitat preferences; E, microhabitat preferences. All images from the holotype, except C, (Paratype EW-MI15-0121); CG, calciferous glands; CL, clitellum; GZ, gizzard; IN, intestine; SV, seminal vesicles; TP, tubercula pubertatis; N, total number of specimens in the dataset. Scale bars: A, B, 2 mm; C, 1 mm.