Octodrilus zicsiniello Csuzdi, Fernández Marchán & Paoletti, 2018

Csuzdi, Csaba, Szederjesi, Tímea, Marchán, Daniel Fernández, Sosa, Irene De, Gavinelli, Federico, Dorigo, Luca, Pamio, Alberto, Dreon, Angelo Leandro, Fusaro, Silvia, Moretto, Enzo & Paoletti, Maurizio Guido, 2018, DNA barcoding of the Italian anecic Octodrilus species in rural (vineyard) and forested areas with description of Octodrilus zicsiniello sp. nov. (Clitellata, Megadrili), Zootaxa 4496 (1), pp. 43-64 : 51

Octodrilus zicsiniello Csuzdi, Fernández Marchán & Paoletti , sp. nov.

( Figure 3 )

Holotype. HNHM /16263 Roncavezzai 5 ( EWITA312-15 ), Roncavezzai , Follina, Treviso, Italy, 23/10/2014, leg. Maurizio G. Paoletti . Paratypes: HNHM /16264, 1 ex. Roncavezzai 8 ( EWITA315-15 ), Roncavezzai 11 ( EWITA318-15 ), 12 ( EWITA319-15 ), 13 ( EWITA320-15 ): Roncavezzai , Follina, Treviso, Italy, 23/10/2014, leg. Maurizio G. Paoletti . HNHM /16264, 1 ex. ( Crevada 6), Crevada 5, 7, 8, 9: Crevada, Treviso, Italy, 03/04/2016, leg. Vladimiro Toniello & Maurizio G. Paoletti. Cavalier 1 ( EWITA325-15 ): Gorgo al Monticano, Treviso, Italy, 08/ 10/2011, leg. Maurizio G. Paoletti. (Altogether ten specimens).

Other material. Ruio 5: Ruio Vallalta, Follina, Treviso, Italy, 27/04/201, leg. Maurizio G, Paoletti . Cesen 1 ( EWITA257-15 ), 3 ( EWITA259-15 ), 5 ( EWITA261-15 ), 7: Cesen Mount , Treviso, Italy, 14/09/2014, Maurizio G. Paoletti. (Altogether five praeadult specimens).

Derivatio nominis. The new species is named in honour of the late Professor András Zicsi, the renowned earthworm taxonomist, and in honour of the geomorphologist Vladimiro Toniello who collected several specimens of this new species. Noun in apposition.

Diagnosis. Length 135–220 mm, diameter 10–12 mm, setae distant. Colour reddish brown with darker midsegments. First dorsal pore in 12/13. Clitellum on ½29, 29 – 38, ¼39, tubercles on ½29, 29 – ½40, 40. Male pores on 15 or 16, small. Nephridial pores irregularly alternate between b and above d. Three pairs of vesicles in 9, 10, 12. Spermathecae seven pairs in 6/7–12/13, open near c. Calciferous glands in 10–12 with large posteriolateral diverticula in 10. Hearts in segments 6–11. Nephridial bladders ocarina-shaped.

External characters. Holotype 220 mm long and 12 mm wide. Number of segments 168. Several tail segments were cut for DNA analysis. Paratypes 135–220 mm long and 10–12 mm wide. Number of segments 160–232 (intact specimens). Colour conserved reddish-brown with darker midsegments. Prostomium slightly epilobous. First dorsal pore at intersegmental furrow 12/13. Setae widely paired. Setal arrangement at segment 43: aa: ab: bc: cd: dd = 3.2:1.4:1.7:1:9 ( Fig. 3B ). Female pores on segment 14, just above seta b. Male pores small on segment 15, in the population from Crevada on segment 16 between setae b–c. Nephridial pores irregularly alternate between setal line b and above d. Clitellum on ½29, 29 – 38, if strongly developed occupying ¼39 as well. Tubercula pubertatis on ½29, 29 – ½40, 40. Glandular tumescences most frequently on 32, 40 ab ( Fig. 3A ).

Internal characters. Septa 6/7–8/9 slightly, 9/10–11/12 moderately thickened, 12/13–14/15 strongly strengthened. Testes and funnels paired in 10–11 enclosed in suboesophageal testis sacs. Three pairs of seminal vesicles in 9, 10 and 12.Vesicles in 9, 10 pear-shaped with mulberry-shaped apex, those in 12 sac-shaped ( Fig. 3C ). Spermathecae seven pairs in 6/7–12/13 with external openings near the setal line c. Calciferous glands in 10–12 with large postero-lateral diverticula in 10. Heart in segment 6–11, with a pair of extraoesophageal vessels in 12. Nephridial bladders ocarina-shaped. Crop large in 15–16, and gizzard in 17–18. Intestine between 21–28 possesses large lateral outcrops which abruptly ends at the beginning of the clitellum. Typhlosolis moderate, ribbed tubeshaped. Longitudinal musculature is of pinnate type.

Remarks. The new species with seven pairs of spermathecae and its clitellar data is most close to Oc. complanatus (Dugès, 1828) and Oc. pseudocomplanatus (Omodeo, 1962) . However, it differs from both in the lack of vesicles in 11 ( Table 1). This character is quite peculiar among the holandric Octodrilus species. The new species is clearly distinguishable also by its barcode sequences ( Fig 1 ).

Figures

FIGURE 1. BAyEsIAn phyLogEnETIc TrEE of ThE InvEsTIgATEd Octodrilus spEcIEs. NUMbErs on ThE brAnchEs rEfEr To posTErIor probAbILITy (PP).

FIGURE 3. Octodrilus zicsiniello sp. nov. A. VEnTroLATErAL vIEw of ThE forE-body. CL = cLITELLUM, Mp = MALE porE, Tb = TUbErcULA pUbErTATIs. B. SETAL ArrAngEMEnTs. AA, Ab, bc, cd, cd rEfEr To sETAL InTErvALs. C. SAgITTAL sEcTIon of ThE gEnITAL rEgIon. s = sEpTUM, sf = spErM fUnnELs, Ts = TEsTIs sAc, vEs 9 = vEsIcLE In 9, vEs 12 = vEsIcLE In 12.