SOME ANATOMICAL, SYSTEMATICAL AND GEOGRAPHICAL DATA ON NENIINAE (GASTROPODA, CLAUSILIIDAE) by F. E. LOOSJES and A. C. W. LOOSJES-VAN BEMMEL Vossenlaan 4, Wageningen, Netherlands (With 38 text-figures and 1 plate) I. INTRODUCTION Up to the moment more than one hundred species and subspecies of Neniinae are known from Central and South America. They are incorporated into 22 genera and subgenera, almost exclusively based on characters of the shells. Only little is known of the anatomy of the animals (Binney, 1871; Binney & Bland, 1871; Baker, 1961; Hesse, 1925; Scott, 1954; Loosjes, 1957; Pilsbry, 1926; Polinski, 1922; Zilch, 1953, 1959). These authors described the radula and/or the genital organs of one or several species. Thus from eleven species the radula has been described and from five the genital apparatus. By the courtesy of Prof. Dr. W. Weyrauch we were able to study the anatomical features of a relatively large number (38) of Peruvian and Argentine Neniinae. We wish to express our most cordial thanks to him for his generosity and also to Dr. B. Hubendick, who provided us with a sample of Nenia tridens (Chemnitz) from Puerto Rico. In Thiele's (1929/31) classification the American Neniinae are grouped into three genera, Nenia, Peruinia and Temesa, based on characters of the shells and of the radula. It turned out impossible to fit the information we found, into this system as it indicates the presence of many more units. In this survey we will follow Zilch's (1960) classification, which enumerates a number of genera and subgenera, based on conchological characters, although the order will be altered according to the results obtained (conf. chapter IV). Thus conchological data of the genera or subgenera involved have to be studied in Zilch (1960), or eventually in Thiele (1929/31). The American representatives of the subfamily Neniinae 1) investigated, 1) Two Asiatic genera are provisionally incorporated into the subfamily. 4 ZOOLOGISCHE VERHANDELINGEN 77 (1966) all have the following characters of radula and genital apparatus. Radula consisting of more than thirty rows of teeth, usually more than one hundred (the estimation of the total number is difficult, because many rows are at the same time in different stages of formation), each row has a central (c) or rhachidian tooth, and on each side lateral (1) and marginal (m) teeth; half a row consists of 9 to 46 elements. There is much variation in the radula, comparing the different genera. The central tooth may have one or three cusps, the laterals may have one and/or two cusps and the marginals three or more cusps. The form of the cusps may be more or less dagger- or crescent-shaped. Small differences in numbers of lateral or marginal teeth appear not to be of much importance, sometimes even the two sides of a row are not identical. It may also occur that the matrix of a certain tooth has a defect so that abnormal teeth are formed at that place in each row. We did not pay attention to these abnormalities. Genital apparatus with a bisexual gland (consisting of groups of sac-like glands), spermoviduct leading via a vesicula seminalis into the ductus semi- nalis with prostate gland on the one side and into the oviduct with albuminous gland on the other. The seminal duct continues into the vas deferens which leads by way of the epiphallus, via the penis into the atrium. The oviduct passes into the clear oviduct, which continues as the vagina after the mouth of the duct of the receptaculum seminis; the vagina leads into the atrium. The vas deferens is distally often a bit wider than proximally, it runs along the clear oviduct and along the vagina, bends near the atrium and accom panies the penis until it passes into the epiphallus. A retractor penis is al ways present, as is the penis ligament. The duct of the receptaculum seminis (pedunculus) may have a distinct bulbus and a diverticulum, the latter ends either on the pedunculus itself, or, near or just at its mouth into the vagina. The diverticulum may be totally absent as well; but in some genera an appendix, often twisted, runs along the clear oviduct and ends distally from the place where the pedunculus enters the vagina. The retractor receptaculum seminis is usually well developed as is the retractor lateralis sinister. The retractor muscle of the left upper tentacle passes between penis and vagina. We never found an embryonic shell in a Nenian oviduct ; such embryos are sometimes found in the uterus of viviparous Clausiliidae, for example in Phaedusa corticina (Pfr.). In the following survey we do not repeat the above mentioned general information on the organs under study for each genus or species separately. We only give the special characteristics of the genera or of the species. Genera and species of which we had no specimens available for dissection are not mentioned here. If no anatomical data are available of the type- LOOSJES & LOOSJES-VAN BEMMEL, NENIINAE 5 species of a genus (or subgenus) but there is anatomical information on other species of that genus, we still give anatomical characters for the genus but with the qualification "presumably the characters are...". The specimens collected by Prof. Dr. W. Weyrauch are indicated with "WW", followed by his collection-number. II. DESCRIPTIONS OF THE GENERA, SUBGENERA AND SPECIES INVESTIGATED Nenia H. & A. Adams, 1855 Type-species : Turbo Widens Chemnitz, 1786. Radula. - + - A —. The tooth-rows are almost rectilinear, with the 1 1 2 1 s—» • central tooth somewhat advanced, the cusps are more or less dagger-shaped. The basal plates and the cusps are rather regularly diminishing in size from the lateral teeth to the outermost marginal teeth. Genital organs. The pedunculus has a diverticulum, the mouth of it divides the pedunculus into a distal and a proximal part. Nenia tridens (Chemnitz, 1786) (fig. 1) Binney (1871) and Binney & Bland (1871) published on the jaw and on the radula; Hesse (1925) described jaw, radula and genital organs; Baker (1961) figured the palliai complex and the penis. The specimens investigated were collected on the island of Puerto Rico, El Yunque, on tree trunks in rain forest, leg. Dr. B. Hubendick. The animals (alcohol specimens) are grey-brown, fading into white near the foot-sole, which is whitish grey. Radula. * + 8=Î8J + We found 8 to 10 lateral teeth (Hesse: 1 1 2 1 8—00 . Ii or 12) with 2 cusps and 19 marginal teeth (Hesse: 20 or 21) with 3 or more cusps. Genital organs. Clear oviduct and vagina about equally long. The proximal part of the pedunculus (from the entrance in the oviduct to the mouth of the diverticulum) is a bit shorter than the distal part of it (from the mouth of the diverticulum to the end of the bulbus of the receptaculum). The bul- bus is spatula-shaped and about twice as long as wide, its width is twice the width of the duct. Diverticulum strong, slightly wider and longer than the distal part of the pedunculus, both are built up in the same way, the one with strong, the other with rather weak longitudinal muscular strips inter nally. The epiphallus is internally provided with 4 longitudinal muscular strips, leaving a star-shaped lumen. The penis is provided with 6 or 7 similar strips. A definite penis papilla could not be found. The vas deferens is bound to the penis by the penis ligament over a rather long distance. These results are in accordance with Hesse's findings. 6 ZOOLOGISCHE VERHANDELINGEN 77 ( I966) Ehrmanniella Zilch, 1949 Type-species: Clausilia (Nenia) quadrata O. Boettger, 1880. Radula. - + - + m The two sides of the tooth-rows form an angle 1 1 2 1 3—00 • 0 of about 1200 (6o° with the axes), with the central tooth at the top, at the fifth tooth on both sides the rows regain a direction more vertical to the axis of the radula. Thus the central teeth and the first three lateral teeth have an advanced position compared with the other teeth of the row to which they belong; the central tooth is vertical to the axis about in line with the third lateral tooth of the previous row. The cusps are more or less dagger-shaped. The basal plates and cusps diminish rather regularly in size from the lateral teeth to the outermost marginal teeth. Genital organs. The pedunculus has a diverticulum, the mouth of it divides the pedunculus into a distal and a proximal part. Fig. I. Nenia tridens (Chemnitz), a, some elements of the radula; b, genital apparatus (b, bulbus of receptaculum seminis; d, diverticulum; p, pedunculus; rp, retractor penis; vd, vas deferens). LOOSJES & LOOSJES-VAN BEMMEL, NENIINAE 7 Ehrmanniella quadrata (O. Boettger, 1880) (fig. 2) The specimens investigated were collected in central Peru, La Florida near Acobamba, Rio Tarma, 3000-3100 m (WW.265). The animals (alcohol specimens) are greyish with a yellowish foot-sole. Radula. f + ^ + 5=^- Jt is n o t e w o r t h y that t he tnird CUSP of t ne first marginal tooth is not formed by splitting up of the main cusp, but of the small side cusp. Genital organs. Clear oviduct short, about one tenth of the length of the vagina and less wide than the pedunculus. The proximal part of the pedun- Fig. 2. Ehrmanniella quadrata (O. Boettger). a, some elements of the radula; b, c, genital apparatus (b, bulbus of receptaculum seminis; d, diverticulum; p, pedunculus; rp, retractor penis; vd, vas deferens). 8 ZOOLOGISCHE VERHANDELINGEN 77 (1966) cuius is short, about as short as the clear oviduct, and very wide; the distal part is short (about half as long as the vagina) and wide, with a distinct bulbus (1^2 times as long as wide). The diverticulum is distally narrow, only the proximal end is wide, it is somewhat longer than the distal part of the pedunculus with the bulbus. The vagina is long, but not strikingly wide. The vas deferens passes into the epiphallus with an externally visible widening. The epiphallus is internally provided with about six muscular strips, regularly distributed over the inner side of the wall. Penis wide, in ternally provided with two very strong muscular strips, which run longi tudinally close to one another, between them is an externally visible groove. The retractor penis is rather weak. Ehrmanniella boettgeri (Pilsbry, 1945) (fig. 3) The specimens investigated were collected in central Peru, Puente Iligyacu, Rio Tarma, 2200 m (W W.300). The animals (alcohol specimens) are brownish-black, the foot-sole is whitish. Radula. ^ + ~ + jdüs"- Here the main cusp and the small side cusp (of the laterals) both may split up in the same tooth, so that the marginals may begin already with teeth with four cusps. Genital organs. Clear oviduct short, about one sixth of the length of the vagina and about as wide as the pedunculus. The proximal part of the pedunculus is short (about as long as the clear oviduct) and wide. The distal part is rather narrow, it has a distinct bulbus (1V2 times as long as wide) ; together with the bulbus, it is more than half as long as the vagina. The diverticulum is narrow, only at its proximal end it becomes wider, it is some what longer than the distal part of the pedunculus with the bulbus. The vagina is neither very long nor very wide. The epiphallus is internally provided with about six weak muscular strips, regularly distributed over the inner wall, one of them may be a bit stronger than the others. The penis is wide and internally provided with two strong muscular strips, which run longitudinally close to one another; between them is an externally visible, groove. The retractor penis is rather weak. Andiniella Weyrauch, 1958 Type-species: Andinia (Ehrmanniella) flammulata Loosjes, 1957. Radula. - + - + -H —. The two sides of the rows form an angle of 1 1 1 1 2 1 3—00 0 about I io° to 1200, with the central tooth at the top, at the fourth tooth the rows regain a direction more nearly vertical to the axis of the radula, thus LOOSJES & LOOSJES-VAN BEMMEL, NENIINAE 9 the central tooth and the first three lateral teeth have a very advanced posi tion, compared with the other teeth of the row to which they belong; the central tooth is vertical to the axis about in line with the third lateral tooth of the previous row. The cusps are more or less dagger-shaped. The basal plates and cusps of the central tooth and of the first three lateral teeth are large in comparison with those of the next teeth of the rows ; from the fourth lateral tooth the elements diminish rather regularly in size to the outermost marginal teeth. The number of elements in a row is comparatively small. Genital organs. The pedunculus has a very narrow diverticulum, the mouth of it divides the pedunculus into a distal and a short proximal part. Fig. 3. Ehrmanniella boettgeri (Pilsbry). a, some elements of the radula; b, genital apparatus (b, bulbus of receptaculum seminis; d, diverticulum; p, pedunculus; rp, retractor penis; vd, vas deferens). Andiniella flammulata (Loosjes, 1957) (fig. 4) Loosjes (1957) described and figured elements of the radula and the genital apparatus. The specimens investigated were collected in central Peru, Cerro Huil- cashpata near Palca, Rio Tarma, 3100 m (W W.1310), paratypes. 10 ZOOLOGISCHE VERHANDELINGEN 77 (1966) The animals (alcohol specimens) are dark brownish-grey, with a whitish foot-sole. Radula. ^+ + + ±=^_. The central tooth is slightly 1 1 1 1 2 1 3—00 J smaller than the first three laterals. Genital organs. Clear oviduct short, about one fifth of the length of the vagina and as wide as the pedunculus. The proximal part of the pedunculus is short, about as short as the clear oviduct, it is rather wide ; the distal part is comparatively long, as long as the vagina or even longer, it has a distinct bulbus (1V2 times as long as wide). The diverticulum is very narrow over its complete length and somewhat shorter than the distal part of the pedunculus. The vagina is not extremely long and rather wide. The vas deferens passes into the epiphallus with a distinct widening; the epiphallus internally has two large and one small muscular strip, forming a T-shaped lumen in cross- section, the penis is short and has a circular lumen, its inner wall is provided with many wrinkled muscular strips. The retractor penis is comparatively weak. Fig. 4. Andiniella flammulata (Loosjes). a, some elements of the radula; b, c, d, genital apparatus (b, bulbus of receptaculum seminis; co, clear oviduct; d, diverticulum; p, pedunculus; rp, retractor penis; vd, vas deferens). LOOSJES & LOOSJES-VAN BEMMEL, NENIINAE 11 Andiniella sztolcmani (Polinski, 1922) (fig. 5) Synonym: Nenia acobambensis Pilsbry, 1945. The specimens investigated were collected in central Peru, La Florida near Acobamba, Rio Tarma, 3000-3100 m (WW.266). The animals (alcohol specimens) are black, with a white foot-sole. Radula. 7 + ~ + ^ + %E~- T h« central tooth is slightly smaller than the first three laterals. Genital organs. Clear oviduct short, about one sixth of the length of the vagina and as wide as the pedunculus. The proximal part of the pedunculus is still shorter than the clear oviduct, it is rather wide. The distal part is comparatively long, about as long as the vagina, it has a distinct bulbus (i1/? Fig. 5. Andiniella sztolcmani (Polinski), a, some elements of the radula; b, c, genital apparatus (b, bulbus of receptaculum seminis; co, clear oviduct; d, diverticulum; p, pedunculus; rp, retractor penis; vd, vas deferens). 12 ZOOLOGISCHE VERHANDELINGEN 77 (1966) times as long as wide). The diverticulum is very narrow over its complete length and as long as the distal part of the pedunculus, the bulbus excluded. The vagina is not extremely long and rather wide. The vas deferens passes into the epiphallus with an externally distinct widening; internally the epi phallus has two large and one small muscular strip, forming a T-shaped lumen. The penis is short and internally provided with many wrinkled mus cular strips, giving a granulated appearance to the inner wall. The retractor penis is rather weak. Peruinia Polinski, 1921 Type-species: Clausilia peruana Troschel, 1847. Radula. f + j + ~f jz^- • The two sides of the rows form an angle of about 900, with the central tooth at the top; at the fifth to seventh tooth the rows regain a direction more nearly vertical to the axis of the radula, thus the central tooth and the first five or six lateral teeth have a very advanced position compared with the other teeth of the row to which they belong; the central tooth is vertical to the axis about in line with the second lateral tooth of the previous row. The cusps are more or less crescent- shaped. The basal plates and cusps of the central tooth and of the first five lateral teeth are large in comparison with those of the next teeth of the rows; from the sixth or seventh lateral tooth the elements diminish rather regularly in size to the outermost marginal teeth. The number of elements in a row is comparatively small. Genital organs. The pedunculus has a very narrow diverticulum, the mouth of it divides the pedunculus into a distal and a short proximal part. Peruinia peruana peruana (Troschel, 1847) (Rg- 6) Polinski (1922) described and figured elements of the radula. The specimen investigated was collected in central Peru, Pan de Azúcar, Rio Tarma, 1400 m (W W.285). The animal (alcohol specimen) is grey and has a reddish foot-sole. Radula. « + •! + Si + 5—15. Genital organs. Clear oviduct rather wide and about as long as the vagina. The pedunculus is very wide, wider than the clear oviduct. The proximal part is short, about one seventh of the distal part, which has a distinct bulbus (about 1V2 times as long as wide). The diverticulum is very narrow over its complete length and distinctly longer than the distal part of the pe dunculus with the bulbus, it enters the pedunculus at the side directed to the clear oviduct. The vagina is short and wide. The vas deferens passes into