The genus Cochlodina A. Férussac in the focus area of its diversity
Hartmut Nordsieck (V.2013)
The focus of the diversity of the genus Cochlodina A. Férussac is in the northwesternmost Dinaric regions (eastern Friuli and Venezia Giulia, western Slovenia, Istria and northwestern high Croatia with Croatian islands). Coastal regions and high mountains side by side, with Mediterranean and central European climates, respectively, and relatively high precipitations in that corner north and east of the Adriatic Sea offer favorable conditions for clausiliids and their diversity. Some selected habitats of Cochlodina species in this area are figured in Nordsieck (2007b: pl. 20).
Because the several Cochlodina species occurring in that area are similar in shell morphology, their distinction is difficult. Add to this that there are species groups like the C. laminata group with species still more similar, and species like C. costata in which several subspecies are distinguished.
The results given in this article are based on the examination of more than 600 samples of Cochlodina species which I have collected in the area concerned (collection Nordsieck, abbreviated: N). At least the same number of samples which are deposited in the collection of the Forschungsinstitut Senckenberg (abbreviated: SMF) were available for this work.
Information on the genital morphology of Cochlodina species was already given in Nordsieck (1963, 1969b, 2007c). In contrast to the shell morphology that of the genitalia is strikingly different. The differences especially in the structure of the male copulatory organs (see figs. 16-20) make possible a determination of the species also when the shell morphology fails for that purpose.
For the terms of shell and genital morphology see Nordsieck (2007b: 177-180). In genital morphology the terms proximal and distal are defined as seen from the gonad (in contrast to Nordsieck 1963, 1969b).
The genus Cochlodina is currently subdivided into the following subgenera (Nordsieck 2007b: 52):
C. (Paracochlodina) H. Nordsieck 1969;
C. (Cochlodinastra) H. Nordsieck 1977;
C. (Procochlodina) H. Nordsieck 1969;
Except for some characters of C. (Cochlodinastra), there are no shell characters which unequivocally separate the different subgenera. They are defined by genital characters.
In C. (Paracochlodina) the diverticulum of the bursa copulatrix is longer than the bursa and its duct. The penis is provided with a reduced penial papilla or instead with an invagination.
In all other subgenera the diverticulum of the bursa copulatrix is shorter than the bursa and its duct.
In C. (Cochlodinastra) instead of a penial papilla the penis is provided with an invagination. In addition, there are some peculiar shell characters (folds of inferior lamella distinct; lunella in part present, outer lobe of clausilium plate pointed and upbent).
In C. (Procochlodina) the penis is provided with a normally developed penial papilla.
In C. (Cochlodina) the penis is provided with a small penial papilla or the latter is reduced, in one group instead of a penial papilla an invagination is present.
A preliminary DNA analysis (16S mtDNA) of nearly all Cochlodina species (Hausdorf unpubl.) confirmed the subgenus classification of the genus, with one exception, that is the systematic position of C. costata. This species did not appear among the species of C. (Cochlodina), but formed a clade with the C. (Procochlodina) species.
This coincides with the fact that the genitalia of C. costata differ from those of the C. (Cochlodina) species in some characters, which so gain in importance. Such a character is the development of the allospermiduct (= Canalis serosus, Nordsieck 1969b), which in the Cochlodina species is widened along the spermoviduct or not.
Therefore, C. costata is separated in a subgenus of its own: C. (Stabilea) de Betta 1870 (type: C. c. costata). It differs from C. (Cochlodina) by the following characters: Allospermiduct not widened along the spermoviduct; penis reduced in size, penial papilla reduced, penial retractor weak (fig. 20).
The remaining species of C. (Cochlodina) have an allospermiduct which is widened along the spermoviduct and a normally developed penis and penial retractor (figs. 16-19).
As is demonstrated by a comparison with related genera of the Alopiinae, especially with the genus Macedonica O. Boettger 1877, the long diverticulum may be the plesiomorphic character state of the bursa copulatrix; consequently the short diverticulum of the other subgenera would be a synapomorphy. Therefore, the other subgenera (except C. (Cochlodinastra)) could be united within one subgenus C. (Cochlodina), but this would not reflect the actual diversity.
Most subgenera have different centres of distribution:
C. (Paracochlodina): Carpathians;
C. (Cochlodinastra): southern Alps and northern Apennines;
C. (Procochlodina): regions around the Tyrrhenian Sea;
C. (Stabilea) and C. (Cochlodina): southeastern Alps and northern Dinaric regions.
The latter two subgenera are treated in this article.
For the history of research and nomenclature of the species concerned see Nordsieck (2005: 35-37).
The characters of the closing apparatus (figs. 1-4) used for the definition of the taxa are the following :
1. Relation of superior and spiral lamella: superior lamella not reaching / reaching / passing by spiral lamella.
2. Middle palatal plica: present, connected with upper palatal plica / not connected with upper palatal plica / missing.
3. Lower palatal plica: not reaching / merging in / running through palatal callus.
4. Lowermost palatal plica: present / missing.
5. Clausilium plate: notch roundish / angular.
6. Clausilium plate: columellar lobe incised / not incised.
7. Inner lamellae endings: spiral lamella penetrating less deeply than / as deeply as / more deeply than inferior lamella.
For the used characters of the genital organs see Nordsieck (1969b).
The species recorded in the mentioned region are listed as follows:
Cochlodina A. Férussac 1821
C. laminata group:
C. laminata (Montagu 1803)
(l. grossa (Rossmässler 1835), l. laminata).
Figs. 5-6, 16.
Shell: Smooth, yellowish or reddish brown; superior lamella reaching or passing by spiral lamella; middle palatal plica present or missing, not connected with upper palatal plica; lower palatal plica merging in palatal callus or running through it; lowermost palatal plica mostly present; notch of clausilium plate roundish, columellar lobe incised or not. Inner lamellae endings: Spiral lamella penetrating less deeply than inferior lamella.
Genitalia (Nordsieck 1969b: 110-114, figs. 2-4; fig. 16): Distal pedunculus mostly shorter than vagina; penis about as long as vagina, proximally with invagination; epiphallus shorter than or as long as penis, distal part shorter than proximal one.
Whole area, except coastal regions, Istria and Croatian islands.
l. grossa: W. Slovenia with adjacent Venezia Giulia and western high Croatia from Soča valley in the northwest to Velebit mountains in the southeast.
C. l. grossa (fig. 6) differs from C. l. laminata by the larger shell, with middle palatal plica more frequently present and columellar lobe of clausilium plate mostly not incised.
C. l. grossa comprises some geographic forms which differ by the development of middle and lower palatal plica: form from Soča valley, type form from western Slovenia (type locality: Podkraj), and form from southwestern Slovenia and high Croatia (= croatica A. Schmidt [non L. Pfeiffer] = inaequalis sensu O. Boettger 1879). According to initial research (Nordsieck 2007c: 24), there are possibly also differences in genital characters. The Soča form resembles C. inaequalis in the development of the palatal plicae, but in genital morphology and according to DNA analysis it belongs to C. laminata.
The forms from remaining Slovenia (major A. Schmidt [non Rossmässler], fig. 5) are similar to other Alpine C. l. laminata.
As to the distributional relations to C. inaequalis see under that species.
C. inaequalis (A. Schmidt 1868)
Shell: Like C. laminata, but middle palatal plica tending to connection with upper palatal plica; lower palatal plica running through palatal callus; columellar lobe of clausilium plate narrowed, not incised.
Genitalia (Nordsieck 1969b: 114, figs. 5-7): Like C. laminata, but epiphallus and its distal part on average longer (epiphallus about as long as penis, distal part mostly about as long as proximal one).
Coastal regions south of the line Duino-Postojna in the north to Crnopac in the south, northeastern Istria and Croatian islands (Krk, Cres, Rab?).
The borderline between C. l. grossa and C. inaequalis is as follows: from west to east Duino–Razdrto–Javorniki mountains–Zagorje–mountain ridge of coastal Croatia. C. inaequalis is not distributed in lower Istria.
In the Javorniki and Hrušica mountains both species occur (A. Schmidt 1868: 32), in one locality (Planina towards Postojna) even syntopically (Nordsieck 2005: 37-38).
Until now, I did not find clear transitions between C. l. grossa and C. inaequalis. The forms from Gorizia and Trnovski gozd regarded as transitional by Gittenberger (1967: 32) belong to the Soča form of C. l. grossa (see under C. laminata).
C. l. insulana (Gittenberger 1967: 32) from the islands of Krk and Cres differs in shell characters not much from the mainland forms; as far as examined, the genital characters are not different.
C. dubiosa (Clessin 1882)
Shell: Like C. laminata, but often more distinctly striated; palatal callus more delimited, lower palatal plica not reaching palatal callus or merging in it.
Genitalia (Nordsieck 1969b: 114-116, figs 8-13): Like C. laminata, but epiphallus and its distal part on average longer (epiphallus longer than penis, distal part about as long as proximal one).
Mountainous regions to eastern Friuli, Trnovski gozd, Javorniki mountains and Celje region in the south.
C. dubiosa is intermediate in shell characters between C. laminata and C. fimbriata, but in genital morphology and according to DNA analysis it is clearly close to the former species.
For a monography of C. dubiosa see Nordsieck (1969a).
C. fimbriata group:
C. fimbriata (Rossmässler 1835)
Fig. 9, 17.
Shell: Whorls more distinctly striated than in C. laminata, mostly yellowish brown; superior lamella not reaching, reaching or passing by spiral lamella; middle palatal plica missing; lower palatal plica not reaching palatal callus; lowermost palatal plica, if present, mostly short; notch of clausilium plate roundish, columellar lobe mostly not incised. Inner lamellae endings like in C. laminata.
Genitalia (Nordsieck 1963: 98, fig. 14; 1969b: 125-126; fig. 17): Distal pedunculus longer than vagina; penis about twice as long as vagina, with short penial papilla beside epiphallic pore; epiphallus shorter than or as long as penis, distal part longer than proximal one.
Whole area to Plješevica and Velebit mountains in the south, except coastal regions, lower Istria and Croatian islands.
In genital morphology (figs. 17-18) and according to DNA analysis C. fimbriata and C. triloba are closely related. As to the distributional relations to C. triloba see under that species.
C. triloba (O. Boettger 1877)
Figs. 10-11, 18.
Shell: Whorls often more distinctly striated than in C. laminata, yellowish brown; superior lamella mostly passing by spiral lamella; middle palatal plica present or missing; lower palatal plica merging in palatal callus; lowermost palatal plica mostly present; notch of clausilium plate tending to be angular, columellar lobe incised, outer part often narrowed (fig. 4). Inner lamellae endings like in C. laminata.
Genitalia (Nordsieck 1969b: 126-128, figs. 27-30; fig. 18): Distal pedunculus shorter than vagina; penis longer than or about as long as vagina, with short penial papilla with epiphallic pore; epiphallus about as long as penis, distal part longer than proximal one.
Coastal regions inclusive whole of Istria south of the line Duino-Postojna in the north to Vratnik pass in the south, island of Krk.
The borderline between C. triloba and C. fimbriata is as follows: from west to east Duino–Razdrto–Pivka–Ilirska Bistrica–Bakar–mountain ridge of coastal Croatia.
Both species occur sympatrically in Učka mountain (C. triloba at lower, C. fimbriata at higher altitudes). Near Razdrto they occur even syntopically.
C. triloba and C. liburnica occur sympatrically on the island of Krk (Käufel collection) and in coastal Croatia below Vratnik pass.
No species group:
C. liburnica (A. J. Wagner 1919)
Fig. 12, 19.
Shell: Whorls smooth, yellowish brown; superior lamella mostly passing by spiral lamella; middle palatal plica mostly present; lower palatal plica running through palatal callus; lowermost palatal plica present; notch of clausilium plate roundish, columellar lobe mostly incised. Inner lamellae endings like in C. laminata.
Genitalia (Nordsieck 1969b: 116-118, figs. 14-17; fig. 19): Distal pedunculus shorter than vagina; penis longer than or about as long as vagina, with reduced penial papilla with epiphallic pore; epiphallus longer than penis, distal part longer than proximal one.
Croatia from Vinodol and Mala Kapela mountains to Crnopac mountain and Una valley, Croatian islands (Krk, Rab), also distributed in Bosnia and Hercegovina (Velež, Ljubišnja).
C. liburnica is similar in shell morphology to C. laminata and C. triloba, but differs from both in genital morphology (fig. 19). It is not closely related to C. triloba, as A. J. Wagner (1919: 72) thought. The distribution of C. liburnica in Bosnia and Hercegovina is insufficiently known; material from W. Serbia and Crna Gora (A. J. Wagner: 72) was not available.
The borderline between C. liburnica and C. costata ungulata, which is only superficially similar to the former species, is in high Croatia between Velika and Mala Kapela.
Cochlodina (Stabilea) de Betta 1870
C. costata (C. Pfeiffer 1828)
(c. costata subgroup: c. costata, c. natisonensis H. Nordsieck 2007, c. psila (Westerlund 1884), c. ungulata (Rossmässler 1835), c. cingulata (L. Pfeiffer 1859; c. curta subgroup: c. curta (Rossmässler 1836), c. istracosta H. Nordsieck 2007, c. schmidti H. Nordsieck 2007; no subgroup: c. intermedia (L. Pfeiffer 1847), c. sigridae H. Nordsieck 2007).
Figs. 13-15, 20.
Shell: Whorls smooth, rib-striated or ribbed; superior lamella mostly passing by spiral lamella; middle palatal plica mostly present, connected with upper palatal plica or not; lower palatal plica running through palatal callus; lowermost palatal plica mostly present; notch of clausilium plate tending to be angular, columellar lobe incised or not. Inner lamellae endings: Spiral lamella penetrating less deeply than, as deeply as or more deeply than inferior lamella, in part inserta present.
Genitalia (Nordsieck 1963: 96, 98, fig. 12; 1969b: 118-121; fig. 20) : Distal pedunculus longer than or about as long as vagina; penis small in size, shorter than vagina, with reduced penial papilla with epiphallic pore; epiphallus longer than penis, distal part about as long as proximal one.
Whole area to Rijeka region and Velika Kapela mountains in the south.
c. costata subspecies group: Mountainous regions distant from the coast.
c. costata (Nordsieck 2007a: fig. 1): Soča valley from Volče nearly to Ročinj, adjacent Idrijca valley to Stopnik (Cerkno?) and Šentviška mountain.
c. natisonensis (Nordsieck 2007a: fig. 2): Natisone valley above Cividale del Friuli up to Tiglio.
c. psila (Nordsieck 2007a: fig. 3): Medea, right side of Isonzo valley from Gorizia southwards.
ungulata (Nordsieck 2007a: fig. 11; fig. 13): Remaining part of distributional range of the subgroup.
c. cingulata (fig. 14): Lubnik mountain near Škofja Loka.
c. curta subspecies group: Coastal regions south of the line Gorizia–Rijeka, whole of Istria.
c. curta (Nordsieck 2007a: figs. 5-6; fig. 15): Left side of Isonzo valley from Fogliano southwards, lower Istria.
c. istracosta (Nordsieck 2007a: fig. 7): Lower Istria (Motovun, region of Pazin).
c. schmidti (Nordsieck 2007a: figs. 8-9): Coastal region between Gorizia and Rijeka (Vipava valley, Karst, higher Istria).
No subspecies group:
c. intermedia (Nordsieck 2007a: fig. 4): Nanos and Hrušica mountains.
c. sigridae (Nordsieck 2007a: fig. 10): Mountain above Trebuščica valley east of Čepovan.
The subspecies groups of C. costata differ as follows:
Shell: In the C. c. costata group the spiral lamella penetrates as deeply as or more deeply than the inferior lamella, in the C. c. curta subgroup less deeply than or as deeply as the inferior lamella.
C. c. intermedia agrees in this character with the first group, C. c. sigridae with the second one.
Genitalia: In the C. c. costata group the diverticulum is pointed, sometimes elongated to a tip, in the C. c. curta group it is rounded (Nordsieck 1969b: 120-121). In the members of the C. c. costata group the distal pedunculus is longer than the vagina, in those of the C. c. curta group both are of about equal length. Because a long vagina is the plesiomorphic state within the subfamily, in the first group the vagina was shortened.
In C. c. intermedia and C. c. sigridae distal pedunculus and vagina are also of equal length, and the epiphallus in relation to penis is shorter than in the other subspecies.
The given characters confirm the exceptional positions of both latter subspecies, which exhibit no transitions to other subspecies (Nordsieck 2005: 38, 2007a: 7).
The borderline between the C. c. costata group and the C. c. curta group is as follows: from west to east Gorizia–Trnovski gozd–Podkraj–Hrušica–Planina–Javorniki mountains–Rijeka.
For definitions and discussion of nearly all C. costata subspecies concerned see Nordsieck (2000, 2007a : 5-7).
C. c. cingulata is a large local form close to C. c. ungulata. The difference in shell size is like that of C. l. grossa compared with C. l. laminata. As far as known, its occurrence is restricted to a mountain near Škofja Loka, W. Slovenia.
Bole (1991: figs. 1B, C) stated that C. c. intermedia and C. c. ungulata occur sympatrically in Lome, Hrušica mountains, without transitions.
In Nanos mountains, e. g., near Podkraj, C. c. intermedia and C. c. schmidti live in close neighbourhood, without transitions (Nordsieck 2005: 38).
In contrast to this, transitions between C. c. costata and C. c. ungulata have been found in Idrijca valley (Nordsieck 2005: 38, figs. 1-4), and between C. c. natisonensis and C. c. ungulata in Natisone valley (Nordsieck 2007a: 6).
In Istria, transitions between the different subspecies of the C. c. curta group could be traced (Nordsieck 2007a: 6-7).
Figs. 5-15. Shells of Cochlodina spp.
Frontal, body whorl dorsal; phot. S. Hof. Actual shell height = H (mm).
5. C. l. laminata (major), SLO, Ljubljana (castle), ex SMF 33094, H 18.4.
6. C. l. grossa, SLO, Podkraj towards Nanos (0.5 km from branch towards Bela), ex N 11220 = SMF 332501, H 21.25.
7. C. inaequalis, SLO, Škoflje near Divača (0.6 km from village at branch towards Mislice), ex N 11070 = SMF 332479, H 19.3.
8. C. d. dubiosa, SLO, Čepovan branch 3.1 km towards Dolenja Trebuša, ex N 11249 = SMF 332512, H 14.5.
9. C. f. fimbriata, SLO, Volče (behind branch towards Čiginj), ex N 10768 = SMF 323229, H 17.9.
10. C. triloba, SLO, Vilenica cave near Lokev (entrance), ex N 10795 = SMF 323257, H 13.7.
11. C. triloba, HR, Sv. Martin on Limski kanal (upper end, left side), ex N 10799 = SMF 323261, H 16.6.
12. C. liburnica, HR, Žuta Lokva (towards Melnice 3 km from branch to Brinje), ex N 11307 = SMF 332517, H 16.3.
13. C. costata ungulata, SLO, Planina 1.7 km towards Postojna (above Planinska jama), ex N 11053 = SMF 332476, H 16.0.
14. C. c. cingulata, SLO, Lubnik mountain near Škofja Loka, ex SMF 126537, H 21.3.
15. C. c. curta, I, Venezia Giulia, Duino (on road to Rocca di Duino), ex N 3990 = SMF 258503, H 14.0.
Figs. 16-20. Male copulatory organs of Cochlodina spp. (schematized, drawn as transparent, flagellum not considered).
16. C. laminata.
17. C. fimbriata.
18. C. triloba.
19. C. liburnica.
20. C. costata.
Abbreviations: dep = distal part of epiphallus, p = penis, pep = proximal part of epiphallus, rp = penial retractor, vd = vas deferens.
Penial papilla and invagination instead of papilla marked by an arrow.
Appendix: List of synonyms
commutata Rossmässler 1836 = C. c. ungulata;
commutatae similis A. Schmidt 1868 = C. c. schmidti;
croatica A. Schmidt 1868 [non L. Pfeiffer 1866] = C. l. grossa;
fusiformis Küster 1876 [non Blanford 1865] = C. c. curta;
fusiformis O. Boettger 1879 [non Blanford 1865 nec Küster 1876] = C. c. schmidti;
gibbosa Westerlund 1878 = C. c. costata;
granatina Rossmässler 1835 = granatinella Clessin 1888 = C. c. ungulata (but see Nordsieck 2005: 35);
heterodoxa Westerlund 1878 = C. c. curta;
inaequalis O. Boettger 1879 [non A. Schmidt 1868] = C. l. grossa;
insulana Gittenberger 1967 = C. inaequalis;
lucida Rossmässler 1836 [non Menke 1830] = C. c. ungulata;
major A. Schmidt 1868 (synonym, validated by O. Boettger 1879) [non Rossmässler 1836] = C. l. laminata;
melanostoma Küster 1860 (synonym, validated by A. Schmidt 1868) = C. l. grossa;
mutata Westerlund 1878 = C. c. ungulata;
pallida Rossmässler 1835 (synonym, validated by O. Boettger 1879) = C. f. fimbriata;
phalerata F. J. Schmidt 1847 = C. f. fimbriata;
polita A. Schmidt 1868 [non Risso 1826] = C. liburnica;
saturata F. J. Schmidt 1847 = C. f. fimbriata;
singularis O. Boettger 1879 = C. c. ungulata;
subcostata O. Boettger 1879 = C. c. curta;
umbrosa Charpentier 1852 (synonym, validated by Küster 1853) = C. c. curta;
utriculus O. Boettger 1879 = C. c. curta;
zeii Bole 1969 = C. c. curta.
Comment on Szalontayova (2013): Variability of Cochlodina
The thesis of Szalontayova deals with the variability of C. laminata and six other C. species in shell morphology and sequences of two mtDNA genes, 16S and COI.
1. Only seven species (in truth eight, see 9., but only half of the C. species) treated, with very different individual numbers, in part extremely small, so that variability cannot be adequately compared.
2. Only two genes, both of mtDNA.
3. Characters of genital morphology, which in Cochlodina are more important than those of shell morphology, not considered.
4. Characters of clausilium, which in Cochlodina are essential ones, not considered.
5. Basic papers on Cochlodina taxonomy not considered, especially that on C. dubiosa (Nordsieck 1969a).
6. For the discussion of the molecular tree (figs. 4-5) no subgenera and no subspecies considered.
7. For the discussion of the molecular tree imbalance of individual numbers not considered. Position of C. triloba in the tree basal, though that species is closely related to C. fimbriata, as proved by genital mophology.
8. mtDNA lineages of C. laminata and C. fimbriata overvalued as taxonomical units, discussed even as cryptic species. Lineages are based on very different individual numbers.
9. Lineage III of C. laminata is another species = C. liburnica. Wrong position within C. laminata, which does not fit the differences to that species, especially in genital morphology, I suppose, because of too low individual number (see 7.).
10. C. laminata is not a young radiating species, as assumed by the author, but relatively old; it is one of the rare species which already existed in Pliocene.
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