Ruthenica, 1999, 9(1): 39-46. ©Ruthenica, 1999

Boreolestes gen. nov., a new of carnivorous from Western Caucasus, and some considerations on the phytogeny of ()

Anatoly A. SCHILEYKO*, Pavel V. KIJASHKO**

*A.N. Severtzov Institute of Problems of Evolution, Russian Academy of Sciences, Leninski Prospect 33, Moscow 117071, RUSSIA **Rostov State University, Bolshaya Sadovaya Street 105, Rostov-on-Don 344006, RUSSIA.

ABSTRACT. Boreolestes gen. nov. with 2 species, pigmented, leaden-colored; indistinct blotches with B. likharevi sp. nov. (type species) and B. sylvestris whitish dots in centre seen at magnification. Horse- sp. nov. from NW Caucasus is described. The shoe-like groove on mantle normally developed or new genus is characterized by a very large mantle presented by only right branch. Orifice of genital covering most of back and by the presence atrium situated slightly behind right tentacle base. of a well-developed perivaginal gland. The new Eyes normally developed. genus is similar to cave-dwelling Troglolestes Ljo- Shell composed of thickened nucleus and very vushkin et Matekin, 1965, but differs from the delicate, fragile spatula. latter by a well-pigmented mantle, presence of Throat length about 1/4 of body length. Nu- perivaginal gland, and absence of vaginal accessory merous retentors attached to throat obliquely-la- organ at the base of spermathecal stalk. It is terally, along one irregular line. Radula of normal suggested that Trigonochlamydidae derived from a zonitoid ancestor. An attempt has been made to "carnivorous" type, but teeth relatively small. Jaw reconstruct the probable phylogenetic relationships rudimentary, transparent, exceptionally thin. in Trigonochlamydidae. Lung cavity very small. Venation scarcely vi- sible. Reproductive apparatus without accessory or- gans except for perivaginal gland. Penis sheath A peculiar family Trigonochlamydidae consists absent. . of obligatory carnivorous slugs. Its range is of a The genus is similar to Troglolestes Ljovushkin relict type, occuping Caucasus and adjacent terri- et Matekin, 1965 in possessing a very large mantle tories of Iran and Turkey. Up to date, 7 monotypic and in the absence of penis sheath and "sperma- genera of the family have been known [Ljovuschkin, tophores" in penis. Boreolestes differs from Trog- Matiokin, 1965; Likharev, Wiktor, 1980; Schileyko, lolestes in the presence of intensive pigmentation 1988]. Here we describe the eighth genus composed of the mantle and perivaginal gland, the absence of 2 species. of distinct papillae on the mantle surface and additional vaginal sac at the base of spermathecal Systematic account stalk. Distribution. NW Caucasus. 2 sp. Mollusks live Trigonochlamydidae Hesse, 1882 on open slopes under stones, at wet conditions. Hesse, 1882: 32 (as subfam. Trigonochlamydina). Etymology. Boreo- (L., northern, indicating the area of the genus at northern border of the family Trigonochlamydinae Hesse, 1882 range) plus -lestes (a robber, traditional ending of generic names in Trigonochlamydidae). Gender Boreolestes Schileyko et Kijashko, masculine. gen. nov. [Диагноз. Фиксированные животные удлиненно- Type species — Boreolestes likharevi Schileyko овальной формы, закруглённые на обоих концах. Ман- et Kijashko, sp. nov. тия очень большая, закрывает почти всю спину жи- Diagnosis. Preserved elongated-ovate, вотного. Поверхность мантии покрыта неясными или чёткими папиллами. Пневмостом расположен близ rounded at both ends. Mantle very large, covering заднего края мантии. Капюшон занимает немного nearly entire back of . Mantle surface covered меньше 1/3 длины мантии. Верхняя поверхность ман- with vague or quite distinct small papillae. Pneu- тии сильно пигментирована, имеет свинцовую ок- mostome situated *not far from posterior end of раску; при увеличении заметны нечеткие пятнышки mantle. Hood occupying somewhat less than 1/3 с белесыми точками в центре. 0 борозда of mantle length. Upper surface of mantle strongly на мантии развита нормально или представлена лишь 40 A.A. Schileyko, P.V. Kijashko

FIG. 1. Boreolestes likharevi sp. nov. Holotype. A — external appearance; B, C, D — shell.

РИС. 1. Boreolestes likharevi sp. nov. Голотип. A — внешний вид; В, С, D — раковина.

правой ветвью. Отверстие атриума располагается по- — west-facing slope of Mount Oshten, environs of зади основания правого глазного щупальца. Psheno-Dakh Lake, isthmus between Mount Oshten and Глаза нормально развиты. Pshekha-su, July 5, 1997; coll. G.B. Bakhtadze (1 pa- Раковина состоит из слегка утолщенного ядра и ratype). тонкой, хрупкой спатулы. Holotype and the paratype from the type locality Глотка занимает около 1/4 длины тела. Много- are stored in the Zoological Institute of Russian Academy численные ретенторы прикрепляются к глотке косо- of Sciences (Saint-Petersburg), other paratypes are in латерально, вдоль одной линии. Радула нормального the Zoological Museum of Moscow State University, "хищного" типа, но зубы относительно маленькие. Nos. Lc-23371, Lc-23372. Челюсть рудиментарная, прозрачная, очень тонкая. Description. Body length of preserved holotype Легочная полость очень маленькая. Венозная сеть (the largest specimen) 10.6 mm. еле заметна. Albumen gland bulky, of irregular shape. Sper- Половой аппарат лишен придаточных органов, кроме перивагинальной железы. Пениальный чехол moviduct capacious. Talon hidden among tissue of отсутствует]. albumen gland. Vas deferens tightly adhering to penis. Penis rather long, internally with two broad longitudinal pilasters covered with numerous mi- Boreolestes likharevi nute papillae. Glandular pads and "spermatopho- Schileyko et Kijashko, sp. nov. res" in penis absent. Penial retractor attached to penis terminally. Free oviduct rather short, about (Figs. 1, 2) same length as vagina. Perivaginal gland well de- veloped, surrounding the vagina and base of sper- Type locality — Oshten-Fisht Mountains, wes- matheca. Spermathecal stalk short, slender, reser- tern part of Great Caucasus, about 2000 m above voir ovate. the sea level. Distribution. NW Caucasus (Oshten-Fisht Mo- Material. NW Caucasus, Oshten-Fisht Mountains., untains). west-facing slope of Mount Oshten, saddle, under stones, June 24, 1997; coll. P.V. Kijashko (holotype and paratype); Etymology. The species is named in honour of — west-facing slope of Mount Oshten, environs of Prof. Ilya M. Likharev, who made a considerable Psheno-Dakh Lake, July 5, 1997; coll. P.V. Kijashko contribution to studying of land mollusks, slugs in (3 paratypes); particular. Boreolestes, new genus of carnivorous slugs 41

В

PVG

FIG. 2. Boreolestes likharevi sp. nov. Holotype. A — reproductive tract and interior of penis; В, С — throat (B — lateral view, С — dorsal view). AG — albumen gland; HG — hermaphroditic gland; P — penis; Pil — pilasters inside penis; PR — penial retractor; PVG — perivaginal gland; R — retentors; RS — reservoir of spermatheca; SOD — spermoviduct; VD — vas deferens. РИС. 2. Boreolestes likharevi sp. nov. Голотип. А — репродуктивный тракт и вскрытый пенис; В, С — глотка (В — вид справа, С — вид со спинной стороны). AG — белковая железа; HG — гермафродитная железа; Р — пенис; Pil — пилястры внутри пениса; PR — пениальный ретрактор; PVG — перивагинальная железа; R — ретенторы; RS — резервуар семеприемника; SOD — спермовидукт; VD — семепровод.

[Диагноз. Длина тела фиксированного голотипа хорошо развита, окутывает вагину и основание про- (самый большой экземпляр) 10.6 мм. тока семеприемника. Проток семеприемника корот- Белковая железа большая, неправильной формы. кий, резервуар овальный.] Спермовидукт объёмистый. Камера оплодотворения скрыта в тканях белковой железы. Семепровод плотно прилегает к пенису. Пенис довольно длинный, внутри с двумя широкими пилястрами, покрытыми много- Boreolestes sylvestris Kijashko, sp. nov. численными маленькими папиллами. Железистые под- (Figs. 3, 4) ушки и "сперматофоры" внутри пениса отсутствуют. Половой ретрактор крепится к пенису терминально. Type locality — environs of Ghooseriple, Mol- Свободный яйцевод довольно короткий, примерно той chepa riverside (right tributary of Belaya River), же длины, что и вагина. Перивагинальная железа NW Caucasus. 42 АA. Schileyko, P.V. Kijashko

FIG. 3. Boreolestes sylvestris sp. nov. Holotype. А, В external appearance; С, D, E — shell. Asterisk — horse-shoe-like groove.

РИС. 3. Boreolestes sylvestris sp. nov. Голотип. А, В — внешний вид; С, D, E — раковина. Звёздочка — подкововидная борозда.

Material. NW Caucasus, Molchepa riverside (right Description. Body length of holotype (the lar- tributary of Belaya River), 6 km from Ghooseriple, mixed gest specimen) 10.0 mm. Both branchs of horse- coniferous-broad-leaved forest (Fagus orientalis, Abies nor- shoe-like groove on mantle normally developed. dmanniana), July 1, 1998, coll. P.V. Kijashko (holotype Surface of mantle covered with numerous, small, and 6 paratypes); — near the same place, July 2, 1998, distinct papillae. coll. P.V. Kijashko (13 paratypes). Holotype and 5 paratypes are stored in the Zoological Albumen gland irregularly triangular. Spermo- Institute of Russian Academy of Sciences (Saint-Peter- viduct and talon as in B. likharevi. Vas deferens sburg), 6 paratypes are in the Zoological Museum of not adhering to penis. Penis moderately long, in- Moscow State University, No. Lc-24424; 7 paratypes ternally with 2 longitudinal pilasters; inner surface are in the Museum of scientific collections of Zoological of penis and pilasters covered with minute papillae. department of Rostov State University. Glandular pads, and "spermatophores" inside penis Boreolestes, new genus of carnivorous slugs 43

HG

PR

FIG. 4. Boreolestes sylvestris sp. nov. Holotype. A — reproductive tract; В — interior of penis and vagina; C, D — throat (C — lateral view, D — dorsal view). Abbreviations as in Fig. 2. Scale bars — 1 mm. РИС. 4. Boreolestes sylvestris sp. nov. Голотип. А — половой аппарат; В — внутреннее строение пениса и вагины; С, D — глотка (С — вид слева, D — вид со спинной стороны). Обозначения как на рис. 2. Масштабные линейки — 1 мм. wanting. Penial retractor attached to penis at base главным образом тем, что вагина в области пери- of vas deferens. Free oviduct somewhat longer than вагинальной железы образует заметное расширение]. vagina. Upper portion of vagina markedly enlarged and surrounded by perivaginal gland along with Discussion base of short spermathecal stalk. Reservoir of sper- matheca rather small, elongate. Trigonochlamydidae are evidently a very pecu- Distribution. NW Caucasus (upper part of Be- liar and ancient family. Its ancient age is indicated, laya River basin). in particular, by the fact that seven of eight genera [Диагноз. Вид близок В. likharevi, внешне отли- of the family are monotypic (only Boreolestes con- чается более светлой окраской, наличием явственных sists of 2 species), and the family is composed of папилл на поверхности мантии (даже у фиксирован- two subfamilies, one of which (Selenochlamydinae ных экземпляров) и тем, что обе ветви подкововидной Likharev et Wiktor, 1980) is also monotypic. борозды нормально развиты. Анатомически отличается To reconstruct possible phylogenetic relation- 44 А.А. Schileyko, P.V. Kijashko

В

FIG. 5. Possible phylogenetic relationships in Trigonochlamydidae. A — zonitid ancestor; В — Troglolestes; С — Boreolestes; D — Parmacellilla; E — Trigonochlamys; F — Hyrcanolestes; G — Drilolestes; H — Lesticulus; I — . Asterisk — "spermatophores" inside penis. РИС. 5. Возможные филогенетические связи внутри Trigonochlamydidae. A — зонитоидный предок; В — Troglolestes; С — Boreolestes, D — Parmacellilla; E — Trigonochlamys; F — Hyrcanolestes; G — Drilolestes; H — Lesticulus; I — Selenochlamys. Звёздочка — "сперматофоры" внутри пениса. ships among genera, we need to discuss the arche- chilini) and Trigonochlamydidae usually have a type of pre-trigonochlamydid organization. We short spermathecal stalk lacking a diverticle. think that the family has originated from a zonitoid 4. Penial retractor in representatives of both ancestor for the following reasons: taxa is attached to penis (or to flagellum) terminally 1. The very unusual structures inside penis in or subterminally. some Trigonochlamydinae are traditionally desig- 5. Although there are no obligatory predators nated as "spermatophores", but they are not ac- among , most of them are omnivorous tually spermatophores, because they are not tran- (not herbivorous), their radulae are of universal sferred to a partner during copulation, and there type, and the closely related family Daudebardiidae is no mechanism which could provide the transfer is composed of predators only. of the "spermatophores" content to a partner. 6. Shells of many Zonitidae are thin and so- Besides, it is unclear how the semen fluid could metimes show a tendency to reduction down to get in this "spermatophore". At the same time, the vitrinoid stage (Godwinia, Vitrinizonites). Likharev penis of Spinophallus (Zonitidae) has conspicuous and Wiktor [1980: 97], when discussing the origin structures inside [Riedel, 1960], which resemble of Trigonochlamydidae, wrote: "Judging by their trigonochlamydid " spermatophores". Muratov internal shell, in which the nucleus is shifted left- ward from longitudinal axis and growth lines on [1998, this volume] suggested that "spermatopho- the spatula are shifted to the right, these slugs... res" of such kind are filled with carbonate buffer originated from snails with succinoid shells". We and probably supply the recipient spermatheca with do not agree with this viewpoint, because, if we this buffer. imagine the stage of reduction next to that of 2. One of conspicuous characters of Zonitidae Vitrinizonites, we get a shell, much resembling those is the presence of perivaginal gland. In species of of Daudebardia, and the next step would be the Boreolestes we have also found a well developed trigonochlamydid shell. perivaginal gland of quite traditional zonitid struc- 7. In addition, skin of the upper surface of ture. cephalopodium of large Zonitidae often has char- 3. Both Zonitidae (at least, Zonitini and Oxy- acteristic bluish-leaden color; back of cephalopo- Boreolestes, new genus of carnivorous slugs 45 dium of some Trigonochlamydidae (Parmacellilla, Tngonochlamys, Hyrcanolestes, Dnlolestes) is simi- larly colored Schileyko [1982, 1986] suggested that Trigo- nochlamydidae have ancient connections with South African endodontoid genus Trachycystis be- cause the penis of Trachycystis contains structures that are somewhat similar to those of some Tngo- nochlamydinae [Sirgel, 1980] This hypothesis, however, contradicts the above-considered facts and should be rejected FIG 6 Shell of Parmacellilla filipowitschi Simroth, 1910 There are two groups in Tngonochlamydinae N Iran, Mazenderan Prov, near Meshkhed, right (Fig 5) species with (rather) small mantle (Par- bank of Babul River Naturhistonsches Museum Basel, macellilla, Tngonochlamys, Hyrcanolestes, Dnloles- No 3960a tes, and Lesticulus), and species with enormously РИС 6 Раковина Parmacellilla filipowitschi Simroth, large mantle, covering most of animal back (Bo- 1910 Сев Иран, пров Мазендеран, близ Мешхеда, reolestes and Troglolestes) In the first group the правый берег р Бабул Музей естественной ис- mantle may be either posterior (Parmacellilla) or тории, Базель, No 3960a medial in position (rest genera) As the posterior position of the mantle is probably an initial con- dition (compare with Daudebardiidae which are immediate derivatives of Zomtidae), Parmacellilla is seemingly the most archaic member of Trigo- of pemal sheath which is absent in all other Tri- nochlamydidae Besides, the shell of Parmacellilla gonochlamydidae filipowitschi Simroth, 1910 retains the distinct traces Lesticulus is a highly specialized troglobiont slug of spiral coiling (Fig 6) lacking coloration and eyes Nevertheless, it differs anatomically from mentioned genera mainly by the The next stage of mantle transformation was its shift forward, a state occurring in all other Tngo- absence of "spermatophores" in the penis and penis nochlamydinae Therefore, the median position of sheath This is probably a result of secondary the mantle is an advanced feature simplification, and this genus is historically con- nected with some extinct forms closely related to Thus we consider Parmacellilla as the most Dnlolestes archaic genus of the Recent tngonochlamydid taxa Selenochlamys, retaining the primitive position of As it has been noted, Troglolestes and Boreolestes mantle, early deviated from Parmacellilla-hke li- have an enormous mantle and lack penis sheath neage, lost the "spermatophores", and changed the Hence, they are related to each other, although internal structure of pemal tube [Likharev, Wiktor, the former is colorless and lives deeply in caves, 1980] whereas the latter is normally pigmented and in- Tngonochlamys, having very small and shifted habits open slopes (lives under stones) We suggest forward mantle, is probably a more or less direct that the succession of habitats indicates trjat Bo- descendant of Parmacellilla Dnlolestes is the next reolestes is an ancestor of Troglolestes Moreover, stage of evolution, because it has somewhat enlar- Boreolestes is the only representative of the family ged mantle, while retaining all main characters of which retains penvaginal gland, an evidence of Tngonochlamys Hyrcanolestes has a peculiar char- origin of Trigonochlamydidae from zomtoid an- acter the penis sheath is attached to penis at both cestor As far as the strange "additional sac" in ends This is undoubtedly a secondary character Troglolestes is concerned, it is unclear whether it and that is why we think that Hyrcanolestes is a is a glandular organ If it is shown to be glandular, descendant of Dnlolestes Hyrcanolestes, Tngonoc- this "sac" is probably a derivative of penvaginal hlamys and Dnlolestes are united by the presence gland

REFERENCES

Hesse P 1882 Miscellen Jahrbuch der deutschen sp n — the first troglobiont slug Bjulleten malakologische Gesellschaft, 9 29-37 Moskovskogo Obshchestva Ispytatelej Pnrody, Bi- ologicheskaja Sektziya, 70(31) 199-232 [In Rus- Likharev IM , Wiktor AJ 1980 Slugs of the sian] fauna of the USSR and adjacent countries (Gas- Muratov IV 1998 Analysis of the phylogenetic tropoda terrestna nuda) Fauna SSSR, new series, 122 Molluscs, 111(5) 437 pp [In Russian] relationships and their systematic implications in the Limacoinei (= Zomtinia) Infraorder (Gas- Ljovuschkin S I , Matekin P V 1965 Biospeologia tropoda, Pulmonata, Geophila) Ruthemca, 8(2) sovietica XXV Troglolestes sokolovi gen n, 47-68 46 А.А. Schileyko, P.V. Kijashko

Riedel A. 1960. Die Gattung Lindbergia Riedel Boreolestes gen. nov., новый род хищных (, Zonitidae) nebst Angaben tiber Vit- слизней из Западного Кавказа и сооб- rea illyrica (A.J. Wagner). Annales zoologici, War- ражения по филогении Trigonochlamydi- szawa, 18: 333-346. dae (Pulmonata) Schileyko A.A. 1982. State of studying of system and phylogeny of pulmonate mollusks. In: Fossil Анатолий А. ШИЛЕЙКО*, Павел В. КИЯШ- gastropods — methods of study, stratigraphical КО** and zoogeographical importance. Dushanbe: 14- *Институт проблем экологии и эволюции им. АН. Се- 16. [In Russian]. верцова РАН, Москва 117071, Ленинский проспект, 33 Schileyko A.A. 1986. On the phylogenetical con- **Ростовский Государственный университет, Ростов- nections of Trigonochlamydidae. Trudy Zoolo- на-Дону 344006, Большая Садовая 105. gicheskogo Muzeya, 24: 187-197. [In Russian]. Описание Boreolestes gen. nov. из северо-запад- Schileyko A.A. 1988. Two new troglobiont species ного Кавказа с 2 видами — В. likharevi sp. of the terrestrial Pulmonata from Georgia (Da- nov. (типовой вид) и В. sylvestris sp. nov. Новый udebardiidae and Trigonochlamydidae). Zoolo- род характеризуется очень большой мантией, gicheskij Zhurnal, 67(11): 1730-1735. [In Rus- sian]. закрывающей почти всю спину животного, и присутствием хорошо развитой перивагинальной Sirgel W.F., 1980. Two new species of the genus железы. Новый род сильно напоминает пещер- Trachycystis from South Africa (, Gas- ного Troglolestes Ljovushkin et Matekin, 1965, но tropoda Pulmonata, Endodontidae). Zoologische отличается, интенсивной пигментацией мантии, Mededelingen, 55(9): 97-113. наличием перивагинальной железы и отсутст- вием дополнительного вагинального органа при основании протока семеприемника. Предпола- гается, что Trigonochlamydidae произошли от зонитоидного предка. Сделана попытка рекон- струировать возможные филогенетические связи внутри Trigonochlamydidae.