Helix (Helix) melanostoma DRAPARNAUD, 1801

Neubert, Eike, 2014, Revision of Helix LINNAEUS, 1758 in its eastern Mediterranean distribution area, and reassignment of Helix godetiana KOBELT, 1878 to Maltzanella HESSE, 1917 (Gastropoda, Pulmonata, Helicidae), Contributions to Natural History 26, pp. 1-200 : 117-121

Helix (Helix) melanostoma DRAPARNAUD, 1801 ( Figs 181–189 )

1801 Helix melanostoma DRAPARNAUD, Tableau de Mollusques de la France: 77 [ France, Marseille].

1839 Helix melanostoma var. candida ROSSMÄSSLER, Iconographie der Land- und Süsswassermollusken 1 (2) (3/4): 9, Taf. 44, Fig. 579 [ohne Vaterland].

1839 Helix melanostoma var. vittata ROSSMÄSSLER, Iconographie der Land- und Süsswassermollusken 1 (2) (3/4): 9, Taf. 44, Fig. 577, 578 [ohne Vaterland] [non Helix vittata O. F. MÜLLER, 1774 ].

1876 Helix melanonixia BOURGUIGNAT , Species novissimae molluscorum: 57 [ Algérie, Mascara].

1882 Helix pachypleura BOURGUIGNAT in Locard, Prodrome de Malacologie FranÇaise: Catalogue général des Mollusques vivants de France: 305 [Environs de Grasse].

1883 Helix uthicensis PECHAUD, Excursions malacologiques dans le nord de l'Afrique de La Calle à Alger, d'Alger à Tanger: 35 [Ruins de Uthica].

1939 Pomatia (Cunula) melanostoma var. doliolum PALLARY , Journal de Conchyliologie, 80: 47 [ Tunis].

Type specimens:

melanostoma : syntype NHMW 14812; H = 28.01; D = 28.98; PH = 18.2; PD = 19.0; PrD = 4.7; W = 4.5. vittata : not searched. melanonixia : syntype MHNG 18156, D = 32.2. pachypleura : syntype MHNG 18177, D = 25.2. uthicensis : syntype MHNG 18185, D = 36.24. doliolum: not searched.

Specimens examined:

Tunisia: Kasserine, Cillum , 35.1671 8.7989 , 19.4.1997, NMBE 512629 /16; ditto, NMBE 503513 /7, NMBE 520822 /2; ditto, SMF 338069/2 ; Kasserine, Sbeitla (= Sufe Tula ), 35.23 9.13, 1961, NMBE 18447 /7; ditto, SMF 280599/12, coll. Schlickum ; ditto, SMF 338063/20 ; Gabes, 33.88 10.12, NMBE 517333 /1; Thuburbo Maius, el- Fahs, antique ruins, 36.4017 9.9033 , 1.1.1995, NMBE 512633 /14; El-Djem, 15 km on the road to north, 35.4186 10.6287 , 3.1.1995, NMBE 512632 /1; Hammamet , 20 km S Hammamet, 36.3254 10.4817 , 2.3.1993, NMBE 512631 /1; Sebkhet Mecheguia , Kairouan, 34.9444 10.0457, 2.3.1993, NMBE 512630 /1; Takrouna, 36.1502 10.3271 , 25.8.2008, NMBE 504093 /2; SMF 9691/1, valley of the Medjerdu close Tunis, Orig. MCH 324, fig. 7; SMF 9703/3, Uthica, 37.0565 10.0622, Orig. MCH 325, fig. 1–6; SMF 172518/1, 10 km E Bizerte, 37.2248 9.9583, coll. Kaltenbach ; SMF 176520/3, 14 km S Sfax, 34.65 10.66, coll. Kaltenbach; SMF 172519/1, 66 km S Sfax, 34.42 10.18, coll. Kaltenbach; SMF 172521/5, Kriba el Mediouni [Quşaybat al Madyūnī], Monastir area, 35.69 10.84, coll. Kaltenbach; SMF 172517/1, 67 km S Tunis, 36.34 10.49, coll. Kaltenbach; SMF 24351/2, Carthago , 36.86 10.33, coll. O. Boettger ; ditto, SMF 74077/3, coll. K.L. Pfeiffer ; ditto, SMF 74086/1, coll. Jetschin ; ditto, SMF 86131/2, coll. Ehrmann ; ditto, SMF 74078/2, coll. Jetschin ; SMF 338060/6, Carthago, ruins of the Therme of Antonius , 36.8543 10.3351, 21.04.1998, LIEB; SMF 172514 /3, 54.5 km S Tunis in dir . Susa, 36.47 10.57, coll. Kaltenbach (tissue sample Korábek) ; SMF 172525/7, 82 km S Tunis, Sidi Kalifa , 36.25 10.425, coll. Kaltenbach ; SMF 161224/3, "Djebel" El Kef, 37.0469 9.5469, coll. Brandt; SMF 172522/4, 9 km N Kairoun in direction Enfidaville , 35.76 10.12, coll. Kaltenbach ; SMF 172524/8, Enfidaville, 16 km W dir. Kairouan, 36.01 10.32, coll. Kaltenbach (tissue sample Korábek) ; SMF 74265/1, Kairouan, 35.67 10.09, coll. K.L. Pfeiffer; Tunis, Ariana, 36.8 10.18, NMBE 22854 /3; SMF 24348/2 , Tunis, 36.7826 10.1875, Orig. Icon. 1036; ditto, SMF 9612/1, around Tunis, Orig. MCH 324, fig. 5–6; ditto, SMF 172576/1, around Tunis, coll. Kaltenbach; ditto, SMF 9714/1 , Tunis, Orig. MCH 324, fig. 10; ditto, SMF 24341/1, coll. O. Boettger ; ditto, SMF 24342/1, coll. Henrich ; ditto, SMF 24336/2, coll. Moellendorff ; ditto, SMF 24357/2, ex Pallary ; ditto, SMF 74098/1, coll. C. R. Boettger ; ditto, SMF 74074/2, coll. K.L. Pfeiffer ; ditto, SMF 74075/2 , Tunis, Fort , coll. K.L. Pfeiffer ; ditto, SMF 74076/2 , Tunis, Belvedere , coll. K.L. Pfeiffer ; ditto, SMF 74097/2, SMF 74085/2 , Tunis, coll. Jetschin; ditto, SMF 74094/3, coll. C. R. Boettger ; ditto, SMF 24349/5, coll. O. Boettger ; ditto, SMF 24360/9, coll. Kobelt ; ditto, SMF 338061/8 , Tunis, Belvedere Park , 19.04.1998; SMF 74092/3 , Beja, 36.73 9.18, coll. C. R. Boettger; ditto, SMF 9703/3, SMF 24359/8, coll. Kobelt ; SMF 74082/3, La Goulette , 36.817 10.305, coll. Jetschin ; ditto, SMF 74093, coll. C. R. Boettger ; SMF 299491/2, Hammamet , 36.40 10.62; ditto, SMF 214883/2, coll. S. H. Jaeckel ; ditto, SMF 280600/5, coll. Kaltenbach (tissue sample Korábek) ; SMF 280598/7, Tozeur, 33.92 8.13, coll. Schlickum; SMF 338062/7, Bizerta, 37.27 9.87, 16.04.1998, LIEB; SMF 338068 /9, Haidra at Thala, 35.565 8.445 , 05.04.1998, LIEB; SMF 338066 /14, Dugga close to Teboursouk, 36.423 9.219 , 07.04.1998, LIEB;; SMF 338064 /10, Bulla Regia close to Jendouba, 36.56 8.76, 09.04.1998, LIEB; ditto, SMF 338067/14; SMF 338065/1 , Mahdia, Cap Afrique, 35.505 11.075, LIEB; SMF 338059 /2, Djerba, Mederine , LIEB; SMF 24354 /1, El Kantara, coll. O. Boettger ; SMF 24340/1, Djebel Batteria close Monastir, coll. O. Boettger; SMF 161233/3, 10 km south Susa, coll. Brandt; SMF 172515/2, 10 km south Susa, coll. Kaltenbach; SMF 172523/19, Sebka Kalbia, on the road to Kairouan, coll. Kaltenbach (tissue sample Korábek) ; SMF 172526/9, 8 km W Libyian border, coll. Kaltenbach.

Algeria: SMF 9689/1, valley of the Bu Merzug, Constantine, Orig. MCH 324, fig. 11–12; SMF 74080/1, Constantine, 36.37 6.62, coll. Jetschin; ditto, NMBE 22851 / 1; ditto, NMBE 22850 / 2; SMF 9693/1, El Guerrah, 36.14 6.61, Orig. MCH 324, fig. 13; SMF 24355/1, Lambessa, 35.49 6.255; ditto, SMF 74079 / 2, coll. Jetschin; ditto, SMF 74091 / 2, coll. C. R. Boettger; ditto, 214882/1, coll. S. H. Jaeckel; ditto, SMF 9688 , Orig. MCH 324, fig. 14; SMF 86127/1, Oran, 35.69 -0.63 coll. Nägele; ditto, SMF 172513 / 1, coll. Kaltenbach; ditto, SMF 74087 / 2, coll. Jetschin; SMF 74090/2, Algier, city, 36.76 3.05, coll. C. R. Boettger; ditto, SMF 24352 , ex Terver; ditto, NMBE 22852 / 6; SMF 86126/4, south of Boghari , 35.84 2.77, coll. Nägele ex Ancey; Mostaganem, 35.93 0.09, NMBE 22849 /4;

Problematic with deep spirals and granules: SMF 9690/1 (sub melanostoma ): Algeria, Saint Denis du Sig, 35.53 -0.19, Orig. MCH 324, fig. 8–9, coll. Kobelt; 24327/1, Constantine, coll. Rossmässler; 24356/3, Saint Denis du Sig, coll. Kobelt.

Diagnosis: shell of medium size, greyish to brilliant white, spherical, teleoconch sculptured by coarse ribs, labial callus and palatal area deep brown to chocolate coloured, umbilicus closed; penis and epiphallus of same length, flagellum moderately long, glandulae mucosae much shorter than dart sac, pedunculus with a thick and short diverticulum.

Description: shell of medium size, spherical, spire depressed to moderately raised, conical; basic shell colour greyish to brilliant white, seldom with chestnut brown spirals, sometimes the upper three spirals fused to form a single broad and darker subsutural area, sometimes all five spirals visible; protoconch medium sized in comparison to shell, its diameter ranging from 4–5. 5 mm, smooth, white whorls; teleoconch of 3–4 whorls, sculptured by coarse ribs, no granulation present, but sometimes with faint subsutural spiral incisions on the body whorl; last whorl slightly descending below the periphery; aperture round- ed, apertural rim broad, labial callus moderately strong, deep brown to chocolate coloured, dark colour expanding to the complete palatal area; columellar triangle small; umbilicus closed or seldom slit-like open in adult shells.

Genital organs ( Fig. 188 ): penis club-shaped, epiphallus of same length as penis; flagellum long, exceeding the length of epiphallus+penis three times; mrp attaching in a central position on the epiphallus; internally, pp1 considerably smaller than pp2, penial chamber long, filled with a few elongate folds, both papillae conical with a central perforation; atrial stimulator an elongated raised lamella with a small terminal knob; female system with a long vaginal tube, dart sac strongly developed, glandulae mucosae with a basic stem branching into a few tubules, much shorter than dart sac; pedunculus stem long, with a thick and short diverticulum branching off the pedunculus in its lower third, bursa copulatrix stem longer than pedunculus stem, vesicle rounded and bent downwards.

Distribution ( Fig. 189 ): This species is known from the complete Mediterranean coast of France, Malta, and from Tunisia to Oran in Algeria, at the border to Morocco.

Remarks: The conchological distinction between H. melanostoma and H. pronuba is sometimes difficult. Usually, the shells of H. melanostoma are smooth besides a pattern of quite strong and coarse ribs; H. pronuba shows a delicate pattern of granules and much finer riblets on the teleoconch. Particularly in southern Tunisia including Djerba, shells are recorded which could be either H. pronuba or H. melanostoma , and it is very likely that in this area, the two species occur in sympatric conditions.

Another remarkable population is recorded from a few localities in Algeria (St-Denis-du-Sig; Mostaganem; Constantine) (Kobelt 1904: 124, Taf. 324, Figs 8–9 ). Here, the shells are ornamented with deep subsutural spiral incisions on the body whorl, which is in clear contrast to the usually smooth shells in H. melanostoma . These shell characters are here considered as local variations, a geographical pattern of this trait is not observed at the moment. Still, the difference of these shells to H. pronuba consist in the teleoconch granulation of the latter.

Figures

Figs 181–187. Helix (Helix) melanostoma DRAPARNAUD, 1801. Fig. 181 syntype melanostoma NHMW 14812, Marseille, D = 28.98; Fig. 182 melanonixia syntype MHNG 18156, Mascara, D = 32.2; Fig. 183 syntype pachypleura MHNG 18177, Grasse, D = 25.2; Fig. 184 syntype uthicensis MHNG 18185, Uthica, D = 36.24; Fig. 185 SMF 311885, Tunesia, Sbeitla, D = 27.41; Fig. 186 SMF 9693, Algeria, El Guerrah, M.-CH. Taf. 324 fig 13, D = 28.4; Fig. 187 SMF 9690, Algeria, Saint Denis au Sig, M.-CH. Taf. 324 fig 8–9, D = 35.4. — Fig. 181 by courtesy of A. Eschner, NHMW, all other photos Neubert, original size.

Fig.188. Helix (Helix) melanostoma DRAPARNAUD, 1801. Genital organs. SMF 311885, Tunesia, Sbeitla, situs 46.31.

Fig. 189. Helix (Helix) melanostoma DRAPARNAUD, 1801. Distribution.

Figs 1–9. Helix (Helix) pomatia LINNAEUS, 1758. Fig. 1 compacta, syntype SMF 9573, D = 50.07, Hungary "Gestrüppe der Berglehnen"; Fig. 2 pulskyana, syntype SMF 9525/2a, Hungary "Inseln der Donau", D = 36.6; Fig. 3 hajnaldiana, syntype SMF 9658, Hungary "Budapest, im botanischen Garten", D = 34.1; Fig. 4 solitaria, syntype SMF 74708/2a, D = 31.1; Fig. 5 sabulosa, syntype SMF 9524, D = 40.5, Fig. 6 expansilabris, holotype SMF 9538, D = 45.5; Fig. 7 luteola, holotype SMF 9527, D = 34.6; Fig. 8 pannonica, lectotype SMF 9535, D = 40.5, Fig. 9 lednicensis, syntype SMF 9534/2a, D = 38.3. — All photos Neubert, original size.