Bollettino della Società Paleontologica Italiana Modena, Novembre 1999

Taxonomy an devolution of Kockelella (Conodonta) from the of ()

Enrico SERPAGLI Carlo CoRRADINI Dipartimento di Scienze della Terra Università di Modena e Reggio Emilia

KEYWORDS- Kockelella, , New taxa, Silurian, Sardinia.

ABSTRACT- Relatively abundant specimens ojKockelella found in Sardinia permit a revision ofmany taxa ofthis important genus and an attempt at a more complete reconstruction ofthe phylogeny ofthe whole group. Besides the two new taxa recently (1998) proposed by us (K. maenniki and K. v. ichnusae), which are here re-described and re-discussed, a new subspecies, K. absidata sardo a ofthe K. absidata group, is proposed. Furthermore the reconstruction ofthe apparatus ojK. crassa is presented. The biostratigraphic value ofthe taxa ofthe genus Kockelella is also stress ed.

RIASSUNTO- [Tassonomia ed evoluzione del genere Kockelella (Conodonta) nel Siluriano della Sardegna (Italia)] - Un numero abbastanza elevato di Kockelelle provenienti dai terreni siluriani della Sardegna ha permesso di effittuare una revisione di diversi taxa di questo importante genere e di tentare una più completa ricostruzione della filogenesi del gruppo. Oltre ai due nuovi taxa proposti recentemente da noi (K. maenniki e K. v. ichnusae), che vengono qui ridescritti e ridiscussi, viene anche proposta una nuova sottospecie, K. absidata sardoa, del gruppo della K. absidata. Inoltre è presentata la ricostruzione dell'apparato di K. crassa. Viene infine discussa l'importanza stratigrafica dei diversi taxa del genere Kockelella.

INTRODUCTION THE PHYLOGENY OF KOCKELELLA

Research in Sardinia during the past three decades The fìrst reconstruction of the phylogeny of by one of us (E.S.) and more recently, by a team from Kockelella was presented by Barrick & Klapper in their Modena University in connection with the preparation authoritative paper of 1976. Subsequently, the problem of the ECOS VII fìeld trip, has allowed the recovery, has been discussed by Kleffner (1994), with regard to from about 70 samples, of conodont elements some Wenlockian forms, and by Fordham (1991), who, belonging to severa! taxa of the genus Kockelella. More in his cladistic reconstruction of the whole Silurian precisely, 673 Pa elements, hundreds of Pb (187), M , also presented a phylogenetic tree for the (236), an d numerous ramiform elements (918) no t yet Kockelella-Polygnathoides Group (p. 9, Fig. 2d). assigned (Tab. 1), have been identifìed. lt is well known (Sweet, 1988) that the oldest species The large number of specimens of Kockelella of genus Kockelella evolved during the middle of elements stimulated us to revise the many taxa of this Llandovery, probably from species like important Silurian genus and to attempt a more abrupta (Aldridge, 1972) and the last species became complete reconstruction of the phylogeny of the group. extinct within the Pol. siluricus Zone. With the present Kockelella, fìrst recorded by Serpagli (1967) from study, the number of taxa assigned to Kockelella Sardinia, have been recovered from Silurian sediments increases from twelve to sixteen. Therefore, we try to either in the "Orthoceras limestone" facies contribute to the understanding of the phyletic (Fluminimaggiore Fm) of the SW or in the "Ockerkalk" relations within the genus Kockelella as inferred from facies of the SE. As has been summarised by Ferretti & the Sardinian sequences as well as from the literature. Serpagli (1996), two distinct types of Silurian Three main lineages, mainly based on the Pa successions occur in Sardinia and are similar to the element, can be recognised, all originating from the sequences exposed in Bohemia and Thuringia, common ancestor K ranuliformis (Text-fìg. 1). respectively (see also Corradini & Serpagli, 1999, this One lineage starts in the latter part of the K volume). ranuliformis interval Zone with K walliseri (early forms) The stratigraphic distribution of Kockelella species evolving from K ranuliformis by developing a latera! is related to the biozonation proposed by Corradini & process adjacent of the cusp. K walliseri lasted up to Serpagli (1998) and discussed further in this sympo- the K crassa Zone, without producing any important sium volume (Corradini & Serpagli, 1999). descendant. In fact, both K cf. stauros sensu Bischoff, 276 E. SERPAGLJ, C. CORRADINI

1986 and K corpulenta became extinct soon in the K v. variabilis evolved from K stauros through late Oz. s. rhenana Zone. The fìrst became differentiated bifurcation of lateral processes and restriction of the through a more developed lateral frocess; the second basai cavity to the area under the processes. At the base through a robust blade bearing aterally expanded of the Oz. exc. hamata Zone, i t produced K v. ichnusae, denticles similat to transverse ridges. in which one lateral process became simple and sub- Also in the K ranuliformis interval Zone, a rounded, and denticles nearly completely fused just population of K ranuliformis started to develop ridge- anterior to the cusp. The lineage ends with K v. ichnusae like denti cles o n the biade, giving raise to K latidentata, in the early Pol. siluricus interval (Text-fìg. l). which become exctinct before the end of the succeeding The third lineage includes three taxa and is Oz. s. rhenana Zone. characterised by Pa elements in which the cusp is always In the late Oz. s. rhenana Zone, K ranulifòrmis gave clearly differentiated from the other denticles. lt rise to more successful stock, which, aÙer having apparently evolved directly from K ranuliformis by provided forms with two small lateral processes (K increasing the number of denticles posterior to the main amsdem), evolved to Pa elements characterised by an denticle, which gradually become a true cusp. From K even more complex platform, which expanded into a absidata absidata, which is the ancestor of this stock, true posterior process (K stauros-K variabilis Group). evolved K a. sardoa through development of crowed

Q) Pe. latialata l\ :o :L"' . ·····----tU- --- "'c: z .<: <( Poi. siluricus > .!2 o 0:: :o :o o lL "' "' o > ::J ...J A. ploeckensis :s:o _J ,!Q o Oz. exc. , c: :::::> '"' _J hamata z > Q) <( ------··;'·"o ··- f= "O ' a. (/) ·"'c;; 0:: K. v. variabilis .o :..: o interval Zone ? (!) "' "' e:::> ------m- --- Ci) K. crassa co z <( Oz. bohemica Ci: ·c: w ---- G> --- -- ::;; "0 Q) .'!! :; o "'E I Oz. s. sagitta c"' o. Q) "' o "O " :::.::::u '' :.! o z _J <( o Oz. s. z o rhenana UJ o :s: z w I (/) K. ranuliformis interval Zone r---u--____..················ >- 0::: LlJ Pt. am. > amorphognath. o o z

::5...J Pt. celloni

Text-fìg. l - Tentative reconstruction of the origin and phylogeny of the genus Kockelella based o n previous srudies (Barrick & Klapper, 1976; Kleffner, 1994) and o n the data from Sardinia. Relationship berween any branch of the tree and the K crassa stock remai n indefinite, as well as with K patu/a and irs possible descendanrA. ploeckensis. The occurrence of different taxa in Sardinia is shown in dark grey; dotted lines indicate highly speculative connections. TAXONOMY AND EVOLUTION OF KOCKELELLA 277 denticles on the amerior process of the Pa element and BIOSTRATIGRAPHICAL MEANING an anterior constriction of the basai cavity. K a. sardoa finally produced K maenniki by developing a long, The biostratigraphic value ofkockelellids has been denticulate lateral process. This lineage starts within the demonstrated by Walliser (1964) and Klapper & late Oz. s. rhenana Zone and survives imo the late Pol Murphy (1976), who used some taxa to name siluricus Zone, therefore including the youngest Kockelella biointervals. With the present study, this value is species before the extinction of the genus. enhanced because 3 of the new 4 taxa proposed (or re- More difficult to/lace in this phyletic scheme are proposed) here can be of great help in making the K crassa stock an K patula stock, which, we prefer biostratigraphic determinations. K crassa was to consider them as a separate groups, apparently not apparently a short-ranged species, limited the basai linked each other nor to the main tree. . K maenniki also ranged briefly together with We believe that K crassa evolved from forms Poi. siluricus, but didn't survive through the latest part characterised by a wider platform (Kockelella sp. nov. of the nominate zone. Kockellella v. ichnusae and K a. A Klapper & Murphy, 1975 sensu Bischoff, 1986), sardoa have a slightly lower biostratigraphic which bears a few nodes on its inner side. This form significance, being the more successful among the new has a more or less rounded-subquadrate outline of the taxa (Text-fig.1). platform, which became almost quadrate in its descendant, K crassa, in which some variations in the pattern of platform demicles also occurred. This connection is, however, speculative, because of the wide stratigraphic gap between the two taxa. SYSTEMATIC PALAEONTOLOGY Even more speculative are the relations between K patu/a and its possible descendams, which Fordham Ali studi ed specimens are stored in the Department (1991) indicates are Kockelella sp. nov. A Klapper & ofEarth Sciences (Palaeontology), Modena University. Murphy, 1975 an d Ancoradella ploeckensis. Therefore, we prefer to consider this stock as a separate group, apparently not linked to any other, as Barrick & KOCKELELLA ABSIDATA Barrick & Klapper, 1976 Klapper (1976, fig. 5) did. Based on the morphological differences of the Pa Looking at the Kockelella phylogenetic tree, as we and the M elements, two phyletically connected have tematively reconstructed it (Text-fig. 1), some subspecies can be distinguished in K absidata: Kockelella comments can be presented about the evolutionary absidata absidata Barrick & Klapper and K absidata history of the genus. sardoa n. spp. K a. sardoa evolved from K a. absidata After its appearance in the late Llandovery, probably in late Gorstian time (Text-fig.l). Specimens with derived from Ozarkodina abrupta-type forms (Sweet, intermediate features have been observed in samples 1988; p.97), the genus Kockelella lasted for about from the Oz. exc. hamata an d A. ploeckensis zones. thirteen million years (from 428 Ma to 415 Ma) imo lt should be pointed out that a further subspecies the early . The stock flourished with varying of this group may be represented by K ortus ortus success, being twice affected by crises before the fina! (Walliser, 1964) sensu]eppsson, 1997. extinction (Text-fig. 1). The first crisis took piace in late Oz. s. rhenana Zone and led to the extinction of nearly ali species usually KOCKELELLA ABSIDATA ABSIDATA lacking a well defined posteri or process (K ranuliformis, Barrick & Klapper, 1976 K latidentata, K corpulenta, K amsdeni, K cf. stauros P!. l, figs. 8-13 sensu Bischoff, 1986, Kockelella sp. nov. A Klapper & Murphy, 1975 sensu Bischoff, 1986) as well as K patula. Pa elemenr 195 7 cf. primus (Branson & M ehi) -WALLISER, The second crisis occurred during the K crassa Zone, pl. l, figs. 1-2. just above the Wenlock-Ludlow boundary, and affected 1964 Ozarkodina fundamentata (Walliser) - W ALLISER, p!. 23, K stauros, Kockelella sp. nov. A Klapper & Murphy, figs. 5-9, 11-15, 21 (?) [only]. 1975, K walliseri and K crassa. The survivors, K v. 1969 Ozarkodina fundamentata (Walliser) - ScHONLAUB, p!. l, fig. 22. variabilis and K a. absidata, successfully evolved, 1971 Ozarkodina fundamentata (Walliser) - SERPAGLI, p!. 21, producing descendams that persisted imo the late P. fig. 13. siluricus Zone, when the entire lineage carne to an end. 1976 Kockelella absidata n.sp.- BARRICK & KLAPrER, pp. 76-77, No Kockelella has been recorded in sediments younger pl. 2, figs. 15-16. than the Pol siluricus Zone (which corresponds to the 1978 Kockelella absidata Barrick & Klapper- RExROAD, NoLAND & POLLOCK, p!. l, fig. 31. leintwardinesis (jritschi linearis) graptolite Zone), when 1983 Kockelella absidata Barrick & Klapper- W ANG & ZIEGLER, the closely related taxon, Ancoradella ploeckensis, also fig. 3, n. 5. became extinct. 1983 Kockelella absidata Barrick & Klapper- BARR!CK, fig. 18G. 278 E. SERPAGLL C. CORRADINI

1993 Kockelella absidata Barrick & Klapper - ScHONLAUB (in Range - In Sardinia K a. absidata appears during Kriz et al.), p!. l, fig. 16. the Oz. bohemica Zone, whereas in the iiterature 1998 Kockelella absidata Barrick & Klapper - SERPAGLI, CORRADINI & FERRETTI, p!. 1.2.1, fig. 8. representatives of this subspecies are known also from 1998a Kockelella absidata Barrick & Klapper - FERRETTI, the Oz. s. rhenana Zone. The iast certain occurrence of CORRADINI & SERPAGLI, pJ. 2.2.1, fig. 12; pl. 2.2.2, fig. 5. K a. absidata is recorded from theA. ploeckensis Zone. However, a probabie (fragmentary) specimen of this Description- P a ELEMENT. Representative specimens taxon has been recovered in the sampie GCIU 4, have a stout, iaterally compressed biade, bearing coming from the Poi. siluricus Zone in Sardinia. denti cles, that are usuaiiy more crowded o n the anterior part. The anterior process is higher than the posterior Studied materia!- 77 ( + 2 questionabie) Pa an d 28 one; i t is more or iess straight and bears up to thirteen M eiements from sampies GA l, GA 2, FRU O, GCIU dosely spaced, iateraiiy compressed dentides. In some 4, SIL Io l, SIL Io 2, SIL ro 3, GALE BK 50, GALE BK specimens the three or four dentides just anterior to 14, GALE BK 18, GALE BK 23, GALE BK 8, GALE the cusp are fused aimost up to their apexes. The BK 21, SF BK 3, SF 7, SF 9, SF BK 12, SF BK 16, PF posterior process is iower, arched downward and gently lA, PF IlA, PF 10, PF ID, PF IQ, PF lF, PF llB incurved; it bears two to six, sometime discrete andSAD BK6. denti cles. The cusp is iateraiiy compressed, redined and siightly iarger than adjacent dentides. The "spathognathodus-iike" basai cavity is wideast beneath the cusp. It narrows gradually towards the KOCKELELLA ABSIDATA SARDOA n. ssp. posterior end of the specimen, whereas anteriorly, after Pl. l, figs. 1-7 a gentle constriction just anterior to the cusp, i t extends as a narrow groove up to the distai end of the anterior Pa element 1964 Ozarkodina jùndamentata (Walliser) -WALLISER, p!. 23, process. figs. 16, 18-19,22-24 [only]. Pb, M, Sa, Sb and Se ELEMENTS. These are ? 1971 Ozarkodina jùndamentata (Walliser)- RExRoAD & CRAIG, (apparently) indistinguishabie from the corresponding pl. 80, fig. 20 [only]. elements of K v. variabilis. 1972 Spathognathodus jùndamentatus Walliser- LINK & DRUCE, p!. 9, figs. 1-11. 1975 Kockelella variabilis Walliser - KLAPPER & MuRPHY, p!. Remarks - The Pa element of K a. absidata has a 10, figs. 8-11. more stout appearance, the anterior biade is usuaiiy 1992 Kockelella absidata Barrick & Klapper- BARCA et al., p!. higher than the posterior one, and has the basai cavity 11 ' fig. 5. a "spathognathodus-iike" outline. Juvenile 1995 Kockelella absidata Barrick & Klapper- BARCA et al., p!. 4, fig. 11. representatives have a Pa eiement with a very narrow 1998 Kockelella absidata Barrick & Klapper - SERPAGLI, biade, with densely iocated denticles, a simiiar CORRADI NI & FERRETTI, pl. 1.2.1 , fig. 7. thickness of the anterior and posterior processes and 1998 Kockelella absidata Barrick & Klapper - CoRRADINI et a basai cavity with an "heart-shaped" outline. al., pl. 1.3.1, fig. 16. M elements of K a. absidata differ from the M element corresponding ones of K a. sardoa in iacking a true 1957 Prioniodina excavata (Branson & Mehl) - WALLISER, p!. anterior process. 2, fig. 16.

EXPLANATION OF PLATE l

Figs. 1-7 - Kockelella absidata sardoa n. ssp. l) Pararype, IPUM 25857, sample GCIU 3 (Pol. siluricus Zone); !arerai view (a) and lower view (b) of Pa element; x80; 2) Pararype, IPUM 27480, sample GCIU 3 (Pol. siluricus Zone); inner-lareral view of M element; x66; 3) Holorype, IPUM 27481, sample GCIU 3 (Pol. siluricus Zone); !arerai view (a) and lower view (b) ofPa element; x66; 4) Pararype, IPUM 27482, sample SIL ro 6 (A. floeckensis Zone); !arerai view (a) and lower view (b) of Pa element; x66; 5) Pararype, IPUM 25858, sample SIL Io 7 (Po. siluricus Zone); !arerai view (a) and lower view (b) of Pa element; x80; 6) Pararype, IPUM 27483, sample SIL'Io 9 (Pol. siluricus Zone); latera! view (a) and lower view (b) ofPa element; x80; 7) Pararype, IPUM 27484, sample SIL Io lO (Pol. siluricus Zone); latera! view ofPa element; x80.

Figs. 8-13 - Kockelella absidata absidata Barrick & Klapper, 1976. 8) IPUM 25861, sample PF llB (Oz. exc. hamata Zone); !arerai view ofPa element; x80; 9) IPUM 27476, sample GALE BK 18 (K crassa Zone); latera! view (a) and lower view (b) ofPa element; x66; lO) IPUM 27479, sample PF l Q (A. ploeckensis Zone); latera! view of Pa element; x80; 11) IPUM 25860, sample PF l Q (A. ploeckensis Zone); latera! view ofPa element; x70; 12) IPUM 27477, sample SF BK 3 ( Oz. bohemica Zone); latera! view (a) and lower view (b) of Pa element; x66; 13) IPUM 27478, sample PF l D (Oz. exc. hamata Zone); latera! view (a) and lower view (b) ofPa element; x66. E. SERPAGLL C. CORRADINL TAXONOMY AND EVOLUTION OF KOCKELELLA Pl. l 280 E. SERPAGLI, C. CORRADINI

1957 Prioniodina cf. armata (Hinde) -WALLISER, p!. 2, fig. 22 biconvex cusp, which is gently curved and slightly [only]. twisted to the posterior. The posterior process is 1964 Neoprionodus multiformis WALLISER, p!. 29, fìgs. 19, 23 [only]. twisted and bears up to nine laterally compressed, reclined, discrete denticles. The denticles closer to the cusp are smaller than others, and more densely Holotype- the specimen illustrated o n P l. l, Fig. spaced. A short anterior process is deflected outwards 3a,b, IPUM 27481. and, in some specimens, descends downwards from the cusp. This process usually bears two denticles. Paratypes (figured)- IPUM 25857-25858,27480, The basai cavity is widest below the cusp and has a 27482-27484. prominent flaring on the inner side of the element, and opens somewhat to the posterior. Locus typicus- Genna Ciuerciu section, dose to the Pb, Sa, Sb and Se ELEMENTS. These elements are village, South East Sardinia, Italy. apparently indistinguishable from the corresponding elements of K v. variabilis and K a. absidata Stratum typicum- GCIU 3. Remarks- Pa ELEMENT. The Pa element of K Derivatio nominis -latin sardous, from Sardinia. absidata sardoa differs from that of K a. absidata in three main features: Diagnosis- The Pa element is characterised by a - the generai o udine of the biade: in K a. absidata the laterally compressed, densely denticulated biade. No anterior process is higher than the posterior o ne, and significant differences exist in thickness between the the biade has a more stout appearance; anterior and posterior part of the biade. The "heart- - the o udine of the basai cavity: in K a. absidata tapers shaped" basai cavity has a sharp constriction just anteriorly more gently whereas in K a. sardoa i t has a anterior to the cusp and gradually tapers posteriorly. "heart-like" shape; -the pattern of denticulation: in K a. sardoa denticles Description- P a ELEMENT. Representative specimens are closely spaced on both processes, whereas in K a. have a very narrow, laterally compressed biade bearing absidata they may be less crowded, up to discrete, on crowded denticles. The anterior process is more or less the posterior process. straight and bears up to twelve closely spaced laterally K absidata sardoa is similar to K maenniki, an d differs compressed denticles. The short posterior process is from i t mainly in the lack of latera! processes. arched downward and gently incurved; it bears two to M ELEMENT. The M element of K a. sardoa differs five closely spaced denticles. The height of the anterior from the corresponding element of K a. absidata in and posterior parts of the biade is similar. The cusp is having a true anterior process; it is different from the laterally compressed, reclined and slightly larger than M element of K maenniki because in the latter the the adjacent denticles. The basai cavity is shallow and denticles are closely spaced and the posterior process is slightly flared on both sides below the cusp. The outer strongly arched. flare of the cavity is usually better developed and may bear a small denticle. The basai cavity has a "heart- K a. sardoa has excellent biostratigraphical value, like" shape, because it tapers gradually towards the spanning an interval from the base of the A. ploeckensis posterior end of the uni t, whereas, after a more or less Zone to within the Pol. siluricus Zone. In fact ali our sharp constriction just anterior to the cusp, i t continues materia!, as well as the specimens reported on the as a narrow groove below the anterior process. synonymy list, is from this interval. M ELEMENT (Pl. l, fig. 2). Specimens are slightly The specimens illustrated from Cellon by Walliser curved and sometimes arched, with a long stout, (1964) as Oz. fundamentata and here reported in the

EXPLANATION OF PLATE 2

Figs. 1-9 - Kockelella crassa (Walliser 1964). l) IPUM 27488, sample SAD BK 2 (K crassa Zone); upper view (a) and lower view (b) ofPa elemem; x66; 2) IPUM 25841, sample GALE BK 18 (K crassa Zone); upper view (a) and lower view (b) ofPa elemem; x80; 3) IPUM 26137, sample SAD BK 2 (K crassa Zone); upper view (a), lower view (b) and !arerai view (c) ofPa element; x80; 4) IPUM 27489, sample SF 7 (K crassa Zone); upper view of Pa element; x90; 5) IPUM 25842, sample GALE BK 18 (K crassa Zone); upper view (a), lower view (b) and upper-lateral view (c) of Pa element; x60; 6) IPUM 25843, sample PF lA (K crassa Zone); upper view of Pa elemem; x80; 7) IPUM 25840, sample SAD BK 2 (K crassa Zone); upper view (a), lower view (b) and upper-lareral view (c) ofPa elemem; x80; 8) IPUM 25917, sample PF lA (K crassa Zone); latera! view ofPb element; x85; 9) IPUM 25916, sample PF l lA (K crassa Zone); latera! view of Pb element; x80. E. SERPAGLL C. CORRADINI, TAXONOMY AND EVOLUTION OF KOCKELELLA Pl. 2 282 E. SERPAGLI, C. CORRADINI

<( o o ...... ;:: ... - :::> :::> - "' <( :::> ;2 ;2 ;2"' "' "';2 ...... "' ...... "' ...... - "' "' "' ..J ..J ..J ..J ..J ..J ..J ..J ..J ...... (3 (!l (3 (3 ..J ..J ..J l! o; o; o; o; o; o; o; o; o; o; o; o;

s s j j j j § j i j § 1 .. 1 1 1 ...... 1 1 ...... l l . i lo. l . . . K. a. absidata Pa 1 1? 4 1 1? M 3 4 8 1 K. a. sardoa Pa 1 4 1 17 3 2? 3 9 5 4 3 4 2 M 6 1 5 5 2 2 1 1 4 K. crassa Pa Pb K. maenniki Pa 5 2 2 21 3 1 4 1 o 1 M 1 2 4 2 4 1 K. ranulifonnis Pa K. stauros Pa K. v. variabilis Pa 9 1 6 3 4 3 14 20 16 5 K. v. tchnusae Pa 1 1 2 3 1 4 1 2 13 4 4 2 ·variabilis arcuo· M 7 2 1 1 3 5 3 1? 6 4 14 1 o 2 2 2 Pb 1 3 1 3 2 2 3 4 3 1 o 4 2 13 4 2 3 4 not assigned Sa 1 5 5 1 3 2 3 1 4 7 9 11 7 1 1 3 24 4 7 13 4 2 ramiforms Sb 3 7 2 2 5 5 3 5 11 16 15 1 14 30 7 4 10 7 2 1 1 Se 3 7 5 4 1 6 6 2 2 3 2 1 20 7 5 17 21 4 11 11 4 2 2 2

o CD N ;! ;!! o ... "' ::: 5! "' CD a> - u. "' .... "' "' "' "' "' "' w"' "' "' "' u. u. u. u. "'..J w "' 5l "' "' "' "' "' "'..J "' "'u. "'u. "'u. "'u. u."' - a: a: a: <( <( <( <( (3 <( <( <( "' "' "' "' "' "' (!l (!l (!l (!l (!l (!l (!l "' "' "' "' "' "' ()"' . s i i .. . E ; ii . ii il ii § § 2 i . 'ii . G s ... s G ! G .. . i l l " i .8 l i . i i " ". K. a. absidata Pa 3 7 3 2 2 1 1 o 2 4 1 9 M 1 2 1? 1 K. a. sardoa Pa 2 1 5 3 M 2 K. crassa Pa 1? 3 1 1 1 o 3 Pb 3 1 K. maenniki Pa 1? 2 6 2 M 1 3 K. ranuliformis Pa K. stauros Pa 1 1 1 2 3 K. v. variabilis Pa 2 4 9 6 1? 92 18 1 1 8 K. v. ichnusae Pa 1 4 2 1 1 3 "variabilis arcuo" M 1 2 2 2 2 1 1 1 19 4 1 3 3 3 3 Pb 3 3 4 3 3 2 1 4 9 18 1 o 7 10 3 5 3 not assigned Sa 1 3 3 1 3 13 17 5 12 4 4 4 9 1 ramiforms Sb 3 2 2 2 2 2 5 5 16 28 6 6 3 2 3 2 6 5 3 Se 3 3 7 1 3 4 3 16 55 18 14 6 3 4 6 6 2

<(

Table l - Distriburion of the different species of Kockelella in samples from Sardinia. Localiry abbreviations: SE Sardinia: GA=Genna 0 0 Arrela, FRU=Monte Fruccas, GCIU=Genna Ciuerciu, SIL l =Silius ! , RMC=Riu Murru de Callus, SBF=San Basilio Fenugu; SW Sardinia: GALE=Galemmu, SF=Sentiero Flumini, CB Ill=Corti Baccas 3'd, PF=Perd'e Fogu, ARG=Argiola, FTM=Fontanamare, SAD=Sant'Anronio Donigala. TAXONOMY AND EVOLUTION OFKOCKELELLA 283 synonymy list, come from the A. ploeckensis (Pl. 23, specimens), usually arranged in an X pattern. A figs. 16, 18) or from the Poi. siluricus Zone (Pl. 23, portion of platform free of demides occurs on both figs. 19, 22-24); the Australian specimens figured by sides of main blade, therefore no ridge connects the Link & Druce (1972) are from the same stratigraphical cusp with the first dentide of the platform. Posterior interval. The specimens from Nevada, recorded by process is short and generally straight. The length/ Klapper & Murphy (1975) as Oz (==Pb) elements of K width ratioOl of the whole element is usually very variabilis, come from the samples where Poi. siluricus high (avg. dose to 2). and/or Oz. conjluens are also present. Pb ELEMENT (after Walliser, 1964). Ozarkodiniform l&.nge- From the base of the A. ploeckensis Zone to elemem characterised by a stout cusp, triangular in cross the Poi. siluricus Zone. section, and by a massive blade, sometimes flaring on o ne side of the platform. Studied materia!- 82 (+2 questionable) Pa and 32 M elements from samples GA l, GA 2, GA 4, GCIU Description- Pa ELEMENT. The anterior blade is long O, GCIU 3, GCIU 5, SIL Io l, SIL Io 4, SIL Io 5, SIL Io and straight and bears 8 to 9 dosely spaced erect 6, SIL P 7, SIL Io 9, SIL Io 10 SIL Io 11, SIL 1°12, demides, which are larger in size near the dista! part of RMC l C; RMC ID, GALE BK 13, PF llB, PF lH, the blade except for the last one, which usually is very PF 5, FTM 2, SAD BK 3A and SAD BK 6. small. In the largest specimens, demicles of the middle part of the blade are partially fused. The cusp is only slightly larger than the adjacem demicles. The posterior KoCKELELLA CRASSA (Walliser, 1964) blade is short and generally straight and bears 3 to 5 Pl. 2, fig. 1-9 closely spaced sub-erect demides. The basai caviry is widely expanded and nearly symmetrical with an almost Pa element quadrate outline. The upper surface of the platform 1964 Kockelella variabilis Waliiser - WALLISER, p!. 16, figs . 2, 8, 11 (oniy). bears three to five dentides on each side; in larger 1968 Kockelella variabilis Walliser- leo & KOIKE, p. l O, p!. 3, specimens the number may increase up to eight to nine. figs. 6-9. Demides are usually arranged irregularly on one side, 1969 Kockelella variabilis Waliiser- ScHONLAUB p!. l , fig . 16. whereas on the other they are almost aligned dose to 1975 Kockelella variabilis Waliiser- KLAPPER & MuRPHY, p!. 9, the outside margin, parallel to the blade. No ridge is fig. 10. ? 1983 Kockelella variabilis Waliiser- WANG & ZIEGLER, pl. 3, present between the cusp and the nearest platform fig. 7. dentide; thus a smooth (unornamented) portion of 1992 Kockelella variabilis Waliiser- BARCA et al., p!. 10, fig. l. the platform lies on each side of the blade. 1993 Kockelella variabilis Waliiser- ScHONLAUB (in Kriz et al.), Pb ELEMENT. The cusp is stout, redined, usually pl. l, fig. 15. 1998 Kockelella circaquadra n.sp. - SERPAGLI & CORRADINI, pp. triangular in cross section with the anterior and the 79-80, pl. l, figs. 3 a-c, 4, 7. posterior margins very sharp. The amerior process is 1998a Kockelella circaquadra Serfagii & Corradini- FERRETTI, slightly longer than the posterior one and bears up to CORRADINI & SERPAGLI, p . 2.2.1 ' fig . 15; p!. 2.2.2, fig. six (exceptionally seven) stout, biconvex dendides; the 15 . posterior process is slightly lower than the other and Pb eiement carries up to four, usually discrete, dentides. O ne side 1964 Ozarkodina crassa n.sp.- W ALLI SER, p. 55, pl. 7, fig. 9; of the blade is slightly expanded in connection of the pl. 24, figs. 14-1 7. cusp; this flared area sometimes may bear a knob (Pl. ? 1969 Ozarkodina crassa Walliser - FAHRAEUS, p. 12, tab. l , p!. 3, fig. 8-9) or even can develop imo a small latera! 2, fig. 5. 1974 Ozarkodina crassa Waliiser - WALMSLEY, ALDRIDGE & process (i.e.: Walliser, 1964, Pl. 24, fig. 17). The basal AUSTIN, fig. 3. caviry extends as a groove under both processes and 1976 "Ozarkodina" crassa Waliiser - BARRICK & KLAPPER, p!. appears asymmetrically developed under the cusp. 2, figs. 12, 13. M, Sa, Sb an d Se ELEMENTS. No description of these 1991 Polygnathoides crassus Waliiser- FORDHAM, p.92. elements is supplied, owing to the poorness of the 197 1 Ozarkodina crassa Waliiser- SERPAGLI, p. 89, p!. 21, figs. l o, 11. available materia!. However, they are apparently similar 1993 Ozarkodina crassa Waliiser- ScHONLAUB (in Kriz et al.), to those described under K v. variabilis. pl. l , figs. 17, 18. 1998 Polygnathoides crassus (Walliser, 1964) - FERRETTI, Remarks-The idea that "Oz. crassa" Walliser, 1964 CoRRADINI & SERPAGu, p!. 2.2.1 , fig. 7; p!. 2.2.2, fig. 8. represents the Pb element of an apparatus induding as Pa element K circaquadra Serpagli & Corradini, 1998 Diagnosis- Pa ELEMENT (after Serpagli & Corradini, 1998). The Pa element is characterised by a widely expanded, almost symmetrical, basal caviry with a l ) Lenght = distance berween rhe anterior and posterior ends of quadrate-subquadrate outline. The platform bears the biade; width = extent of the anterior margin of the piatform, three-five demides on each side (up to nine in larger measured perpendicuiarly to the biade. 284 E. SERPAGLI, C CORRADINI has been kindly suggested to us by Jim Barrick (pers. BK 50, SF BK 3, SF BK 17, SF 7, SF 8, PF lA, PF comm. 11/03/1999). lt follows that, according to IlA and SAD BK 2. the priority laws, the species must be named Kockelella crassa (Walliser, 1964). Pa elements belonging to K crassa differ from both KoCKELELLA MAENNIKI Serpagli & Corradini, 1998 K v. variabilis an d K patula in the generai shape of the Pl. 3, fig. 1-12 basai cavity. Sinuses in the margin of the cavity of this species are not developed as between the secondary Pa element ? 1975 Kockelella variabilis Walliser -l

EXPLANATION OF PLATE 3

Figs. 1-12 - Kockelella maenniki Serpagli & Corradini, 1998. l) Paratype, IPUM 25846, sample GCIU 3 (Poi. siluricus Zone); upper view (a), upper-lareral view (b) and lower view (c) of Pa element; x80; 2) Paratype, IPUM 25848, sample GCIU 2 (Poi. siluricus Zone); upper-lateral view of Pa element; x80; 3) Paratype, IPUM 25850, sample GCIU 3 (Poi. siluricus Zone); upper view (a) and lower view (b) ofPa element; x80; 4) Paratype, IPUM 27485, sample GA 4 (Poi. siluricus Zone); upper view (a) and upper-lateral view (b) ofPa element; x80; 5) Paratype, IPUM 25853, sample PF 11 B (Poi. siluricus Zone); latera! view of Pa element; x80; 6) Paratype, IPUM 26148, sample GCIU 3 (Poi. siluricus Zone); upper view ofPa elemenr; x80; 7) Paratype, IPUM 25849, sample GCIU 3 (Poi. siluricus Zone); upper view ofPa element; x80; 8) Paratype, IPUM 27486, sample SIL Io 9 (Poi. siluricus Zone); upper view (a) and lower view (b) ofPa elemenr; x66; 9) Paratype, IPUM 26141, sample PF l H (Poi. siluricus Zone); upper view (a) an d lower view (b) of Pa elemenr; x80; l O) Holotype, IPUM 25845, sample GCIU 3 (Poi. siluricus Zone); upper view (a) and lower view (b) of Pa elemenr; x80; 11) Paratype, IPUM 25847, sample GCIU 3 (Pol. siluricus Zone); upper view of Pa elemenr; x80; 12) Paratype, IPUM 27487, sample GCIU 3 (Poi. siluricus Zone); inner-lateral view of M elemenr; x80. E. SERPAGLL C. CORRADINL TAXONOMY AND EVOLUTION OF KOCKELELLA P!. 3 286 E. SERPAGLI, C. CORRADINI conspicuous, usually curved on one side and arched "spathognatodus-like" appearance and, if demicles on downward. Cusp well developed and differentiated latera! process are not yet developed, is not easy to from the other denticles. separate them from true "Spathognathodus". M ELEMENT. The M element of K maenniki is very Description- Pa ELEMENT is slender, slighdy curved similar to that of K a. sardoa, but has a more arched and arched. Biade is very narrow and laterally posterior process and a denticulate anticusp instead of compressed; its anterior part is usually straight and a real anterior process. bears from 8 to 12 closely spaced, laterally compressed K maenniki has good biostratigraphical value, being denticles. The conspicuous posterior biade is usually limited to the early-middle part of the Pol. siluricus curved to one side and arched downward; it bears up Zone. In fact, ali our materia!, as well as the specimens to 6 closely spaced, laterally compressed denticles. reponed on the synonymy list, are from this interval. The slighdy reclined cusp is well developed, always Specimens of K maenniki from the "Nordliche separable from the other denticles and located on the Grauwauckenzone" (Austria) have been recorded in posterior third of the uni t. samples in which Pol. siluricus or Oz. conjluens have Platform is strongly asymmetrical and typically is been found (Flajs & Schonlaub, 1976, p l. 4, fìgs. 17- strongly developed on outer side, where a simple long 19). Also, the specimen illustrateci by Mannik & process bears up to fìve (commonly three) aligned Malkowski (1998, pl. 2, fìg. 12) from the Pol. siluricus denticles, which are usually slighdy proclined. The Zone in the Goldap Core (Poland), and identifìed as inner side of the platform is usually smooth, but in Kockelella sp., is in reality K maenniki. some specimens a single small denticle may occasionally be present. The basai cavity is wide below the platform Range-Early-middle p art of the Pol. siluricus Zone. and extends as a narrow groove to the ends of the processes. Studied materia!- 73 (+l questionable) Pa an d 19 M ELEMENT (Pl. 3, fìg. 12). Specimens are slighdy M elements from samples GA 3, GA 4; GCIU O, GCIU curved and usually arched, with a long, stout, biconvex 2, GCIU 3, GCIU 5; SIL I 7, SIL I 8, SIL I 9, SIL I 12; cusp. The cusp is gendy curved and slighdy twisted to RMC lB, RMC l C; GALE BK 13; CB III-BK la; PF the posterior. The posterior process, usually strongly lH, PF 5; FTM l and FTM 2. arched and twisted, bears up to ten laterally compressed, reclined, closely spaced denticles. An anticusp-like anterior process bears two or three laterally compressed denticles crowded adjacent to the cusp. The basai cavity KO CKELELLA RANULIFORMIS (Walliser, 1964) has a prominent flaring of margin on the inner si de of Pl. 7, fìg. 10 the unit and opens somewhat to the posterior. Pa element Pb, Sa, Sb and Se ELEMENTS. These elements are 1964 Spathognathodus ranuliformis W ALLISER, p. 82, cav. 6, fig. apparendy indistinguishable from the corresponding 9; pl. 22, figs. 5-7. elements of K v. variabilis and K a. absidata. 1976 Kockelella ranuliformis (Walliser)- BARRJCK & KiAPPER, p. 76, pl. 2, figs. 1-11. 1983 Kockelella ranuliformis (Walliser)- BARRJCK, fig. 181. Remarks - Pa ELEMENT. The Pa element of K 1995 Kockelella ranuliformis (Walliser) - SIMPSON & TALENT, p. maenniki differs from that of K absidata sardoa by the 135, pl. 6, figs. 2-7 (only) (cum .ryn.). occurrence of a latera! process; it is unlike K stauros 1998a Kockelella ranuliformis (Walliser) - CoRRADINI, FERRETTI Barrick & Klapper in having a typically asymmetrical & SERPAGLI, pl. 3.3.1, fig. 4a, b. basai cavity and a single latera! process. The outer latera! process is usually anteriorly bent, but in few Remarks - The round basai cavity at the posterior specimens it is perpendicular to the biade, or even end of the Pa element, and the absence of latera! posteriorly directed. Some juvenile specimens have a processes are the main features of this species. No more

EXPLANATION OF PLATE 4

Figs. 1-7 - Kockele!la variabilis ichnusae Serpagli & Corradini, 1998. l) Pararype, IPUM 25839, sample PF llB (Poi. siluricus Zone); upper view (a) and lower view (b) of Pa element; x80; 2) Pararype, IPUM 27490, sample FTM 2 (Poi. siluricus Zone); upper view (a) and lower view (b) ofPa element; x66; 3) Pararype, IPUM 25836, sample SIL ro 5 (A. ploeckensis Zone); upper view (a) and lower view (b) ofPa element; x80; 4) Pararype, IPUM 27491, sample SBF 5 (A. ploeckensis Zone); upper view ofPa element; x66; 5) Holorype, IPUM 25834, sample SIL Io 5 (A. ploeckensis Zone); upper view (a), lower view (b) and upper-lateral view (c) of Pa element; x60; 6) Pararype, IPUM 25838, sample PF l Q (A. ploeckensis Zone); upper view (a) and lower view (b) of Pa elemenr; x60 7) Pararype, IPUM 25835, sample SBF 5 (A. ploeckensis Zone); upper view of Pa element; x80. E. SERPAGLJ, C. CORRADINI, TAXONOMY AND EVOLUTION OF KOCKELELLA P!. 4 288 E. SERPAGLJ, C. CORRADINI information can be supplied with the scarce available KOCKELELLA VARIABILIS WaJliser, 1957 materia!. Range- From the Pt. celloni Zone (Pt. am. angufatus Based on the morphology of the Pa element, two Subzone) to Oz. s. rhenana Zones subspecies were ricognised in K variabilis: Kockelelfa variabilis variabilis Walliser and K variabilis ichnusae Studied materia!- 2 Pa elements from sample ARG C. Serpagli & Corradini.

KOCKELELLA STAUROS Barrick & Klapper, 1976 Pl. 7, figs. 8-9 KocKELELLA VARIABILIS VARIABILIS Walliser, 1957 Pl. 5, figs. 1-13; pl. 6, figs. 1-9; pl. 7, figs. 1-7 Pa element 1976 Kockelelfa stauros BARRJCK & l

EXPLANATION OF PLATE 5

In order to show variation from juveniie to adu!t Pa elements, ali specimens illustrateci in this piace come from the same sampie and have che same magnification. Two additionai specimens belonging to the same growing series are illustrated in the next plate (P!. 6, figs. 8-9).

Figs. 1-13 - Kockelella variabilis variabilis Waliiser, 1957. Ali specimens from sampie GALE BK 23 (K v. variabilis Zone); x66. l) IPUM 27493/1; upper view ofPa element; 2) IPUM 27493/2; upper view ofPa element; 3) IPUM 27493/3; upper view ofPa element; 4) IPUM 27493/4; upper view ofPa element; 5) IPUM 27493/5; upper view ofPa element; 6) IPUM 27493/6; upper view of Pa element; 7) IPUM 27493/7; upper view of Pa element; 8) IPUM 27493/8; upper view ofPa element; 9) IPUM 27493/9; upper view ofPa element; lO) IPUM 27493/10; upper view (a) and iower view (b) of Pa element; 11) IPUM 27493/11; upper view (a) and iower view (b) ofPa eiement; 12) IPUM 27493/12; upper view (a) and iower view (b) ofPa element; 13) IPUM 27493/13; upper view (a) and iower view (b) ofPa element. E. SERPAGLI, C CORRADINI, TAXONOMY AND EVOLUTION OF KOCKELELLA P!. 5 290 E. SERPAGL!, C. CORRADINI

1998a Kockelella variabilis variabilis Walliser - FERRETTI, CoRRA- process on both sides of the blade in the posterior DINI & SERPAGLI, yJ. 2.2.1, fìg. 17; p l. 2.2.2, fìg. 16. part of the element. 1998 Kockelella vartabtlis Walhser - MANNIK & MALKOWSKI, p l. 2, fìg . 8. The anterior process is long, straight and relatively thick; it bears up to 11 laterally compressed denticles; Pb element they are very closely spaced (up to fused) proximally, 1957 Ozarkodina ziegleri n.sp. W ALLISER, p. 41, p l. l , fìgs. 26- whereas one or two, stout, high and discrete, occur in 30. 1964 Ozarkodina ziegleri ziegleri Walliser - W ALLISER, p. 63, p l. the distal part; the blade ends with one or two short, 8, fìg. 11; p l. 25, fìgs. 1-1 O; texr-fìg. 3 i, k. small denticles. The denticle placed where the ridges of the lateral M element processes meet the junction of the anterior and 19 57 Prioniodina cf. armata (Hinde) - W ALLISER, p l. 2, fìg. 21 posterior processes can be considered as the cusp, [only]. 1964 Neoprionodus multi{ormis n.sp. W ALLISER, p l. 29, fìgs. 14, which, however, does no t differ in size from the adjacent 17- 18, 21-22, 25 [only]. denti cles. 197 1 Neoprionodus multiformis Walliser - SERPAGLI, p l. 22, fìg. The posterior process is short and curved and bears 9. up to fìve laterally compressed, closely spaced, 1992 K variabilis Walliser, M element- BARCA et al., p l. l O, fìg. 2. sometime partially fused denticles. Bifurcated lateral processes aredresent on both sides Sa element of the blade. They are connecte by a narrow ridge. 1957 Trichonodella inconstans n.sp. W ALLISER, pp. 50-51, p l. 3, The outer lateral process is usually more developed than fìgs. 10-17. the inner one; ir bears two ridges of3-5 denticles. The 1964 Trichonodella inconstans Walliser- W ALLISER, p. 90, p l. 8, fìg. 11; pl. 30, fìgs. 10-11. angle beween these ridges is up to 90°. In adult specimens i ridges protrude out of the platform, Sb element generally the posterior one is better developed than 1957 Lonchodina greilingi n.sp. WALLISER, pp. 38-39, p l. 3, fìgs. the other. In few specimens these ridges may branch 20-26. 1964 Lonchodina greilingi Walliser- W ALLISER, p. 44, pl. 8, fìg. further. The denticle pattern on the inner lateral process 7; pl. 30, fìgs. 7-9. is extremely irregular, when the denticles form two short ridges bearing 1-3 denticles each. Se element The basal cavity is wide and slightly asymmetrical, 1957 Ligonodina diversa n.sp. WALLISER, p. 36, pl. 2, fìgs. 11 , having a heart-shaped (subtriangular) outline in small 13-14 [only]. 1964 Ligonodina salopia Rhodes - W ALLISER, p.41-42, pl.8, fìg.9; specimens and a polygonal (approximately subrectan- pl.32, fìg.5 , l O. gular) in large ones, owing to the strong development of the posterior ridge of the outer lateral process. The basal cavity extends as a deep groove under the anterior Amended diagnosis- The Pa element [of K variabilis blade. variabilis] is characterised by lateral processes typically branched (adult specimens) and a length/width rario Pb ELEMENT (Pl. 6, fig. 6; pl. 7, fig. 5). Cusp is large usually very low (avg. dose to 1.6). The wide, slightly biconvex and reclined. Anrerior and posterior processes asymmetrical basal cavity, has a heart-shaped are more or less equal in length and bear six to eight (subtriangular) oudine in small specimens and a slightly compressed denticles. The anterior process is polygonal (approximately subrectangular) in large ones, usually more robust than the posterior one and and is generally confined to the area under the lateral denricles on i t may be partially fused. The basal cavity processes and posterior blade. extends as a groove under bothdrocesses and appears under the cusp as a rounde flaring expansion, Description- Pa ELEMENT. Representative specimens definitely larger o n the outer side. The anterior groove are straight to slightly curved, with a lateral bifurcated is narrower and deeper than the posterior one.

EXPLANATION OF PLATE 6

Figs. 1-9 - Kockelella variabilis variabilis Walliser 1957. All specimens from sample GALE BK 23 (K v. variabilis Zone). l) IPUM 27493/21; inner-lateral view of Se element; x50; 2) IPUM 27493/22; inner-lareral view of Se element; x66; 3) IPUM 27493/18; inner-lareral view ofM element; x50; 4) IPUM 27493/19; posrerior view of Sa element; x50; 5) IPUM 27493/20; posterior view of Sb element; x66; 6) IPUM 27493/17; inner-lateral view of Pb element; x50; 7) IPUM 27493/14; upper view (a) and lower view (b) of Pa element; x66; 8) IPUM 27493/15; upper view (a) an d lower view (b) of Pa element; x66 9) IPUM 27493/ 16; upper view (a) and lower view (b) of Pa element; x66. E. SERPAGLL C. CORRADINL TAXONOMY AND EVOLUTION OF KOCKELELLA Pl. 6 292 E. SERPAGLL C. CORRADINI

M ELEMENT (pl. 6, fig. 3; pl. 7, fig. 7). Specimens processes of different length. The cusp is long, slender are slighdy curved with a long stout, biconvex cusp, an d reclined, sometimes bearing a narrow keel o n both which is gendy curved and slighdy twisted to the lateral sides. The posterior process, longer than the posterior. The posterior process bears six to nine erect, anterior one, arches sharply downwards from the cusp discrete denticles, (sub)round in cross section. A true and is slighdy incurved; it bears 6 to 7 round, erect, anterior process is missing, whereas a short anticusp- discrete denticles. The anterior process, somewhat like extension has been observed in some specimens. twisted, forms an angle of about 90° with the posterior Sometimes, a small, partially fused with the cusp an d bears 4 to 6 denti cles. The processes lie o n different denticle may be present on the anterior margin; also a planes, forming an angle up to 90° degrees in strongly second denticle has been occasionally observed. The bowed specimens. The basai cavity is expanded basai cavity opens somewhat to the posterior and has a posteriorly as a round protrusion that gradually closes prominent flaring margin on the inner side of the towards the end of the processes. element. Se ELEMENT (Pl. 6, figs. 1-2; pl. 7, fig. 6). Specimens Sa ELEMENT (p l. 6, fig. 4). Specimens are symmetrical have a long, stout reclined cusp, sometimes bearing a with a slender, long cusp, sub-oval in cross section, narrow keel in the anterior part of the inner side. The which sometimes bears a narrow keel on both lateral cusp has a sub-oval cross section near the base, whereas sides. The two straight, equal, lateral processes are in the upper part it shows a flat anterior margin. The directed sharply downwards from the cusp an d diverge posteri or process is long, sometimes slighdy arched an d at an angle dose to 90°. Each process bears about six turned towards the outer side, bearing up to twelve round, erect, discrete denticles. A more or less developed reclined, discrete denticles, rounded in cross section. posterior expansion of the basai cavity, in form of a Antero-lateral process forms a more or less square angle rounded lip, is always present. with the posterior process and descends sharply downward from the cusp at different angles; it bears Sb ELEMENT (Pl. 6, fig. 5; pl. 7, fig. 4). Specimens fìve to seven discrete, slighdy posteriorly bent denti cles, are asymmetrical and bowed, with two arched rounded in cross section.

l J i v}

A 2 3 4 5 6 8 9

,-r ' \ v\ / B 2 3 4 5 6 7 8 9 10

Texc-fig. 2 - Carnera lucida drawings of some specimens of K v. variabilis arranged in sequences to show graduai morphologic changes from juvenile co adulc specimens. Each sequence is based on specimens of che sarne sample co point out rhac some juvenile specimens can be wrongly referred co K stauros. Magnificacion: x40. A) sample GALE-BK 8 (A. ploeckensis Zone), "Orthoceras lm." of the Fluminimaggiore Fm., A. ploeckensis Zone, SW Sardinia; che fourrh and eighch specimens have been drawn reversed. B) sample SIL r• 4, (A. ploeckensis Zone), "Ockerkalk" facies, SE Sardinia. TAXONOMY AND EVOLUTION OF KOCKELELLA 293

Remarks- Pa ELEMENT. In severa! samples from KOCKELELLA VARIABILIS ICHNUSAE Sardinia, from both the Ockerkalk and Orthoceras Serpagli & Corradini, 1998 limestone facies, it is possible to recognise complete Pl. 4, fig. 1-7 sequences from juvenile to adult specimens, showing ali intermediate stages (Text-fig. 2; pls. 5, 6). Sequences Pa element 1964 Kockelella variabilis Walliser - WALLISER, p!. 16, figs. l?, begin with "Spathognathodus-like" specimens without 5?, 7, 12. any denticulate latera! process (Text-fig. 2, A1, B1; pl. 1971 Kockelella variabilis Walliser - RExROAD & CRAJG, pl. 82, 5, fig. 1), showing only a crest on one or both sides of figs. 8-10. the biade, followed by "stauros-like" specimens with 1971 Kockelella variabilis Walliser - REXROAD & NICOLL, p!. 2, o ne or two denticles o n each side (Text-fig. 2, fu-3, B2-3; fig. 8. 1972 Kockelella variabilis Walliser- LINK & DRUCE, pl. 3, figs. pl. 5, figs. 2-3). The sequence continues, after further 11, 12, 15, 16; text-fig.21. intermediate stages, with specimens bearing one 1972 Kockelella variabilis Walliser- VAI, pl. 32, fig. l. branched latera! process (Text-fig. 2, A4, B4-5; pl. 5, figs. 1975 Kockelella variabilis Walliser- ScHONLAUB & ZEZULA, p!. 4-5) and ends with specimens bearing branched latera! l, fig. l. 1976 Kockelella variabilis Walliser- EBNER, pl. 2, fig. 3. processes o n both sides of the element (Text-fig. 2, AB-9, ? 1977 Kockelella variabilis Walliser - CooPER, p! .17, figs. l, 5. Bw; pl. 5, figs. 11-13; pl. 6, figs. 8-9). ? 1980 Kockelella variabilis Walliser- ScHONLAUB, pl. 6, fig. l. The Pa element of K v. variabilis differs from that 1995 Kockelella variabilis Walliser- BARCA et al., p!. 4, fig. 15. of K v. ichnusae mainly in having a more symmetrical 1998 Kockefella variabilis ichnusae n.sp. SERPAGLI & CoRRADINI, platform, no rim on its margin and by the lack of a pp. 80-82, p!. l, figs. la-c, 2. 1998 Kockelella variabilis ichnusae Serpagli & Corradini - true crest produced by some fused denticles anteriorly SERPAGLI, CORRADINI & FERRETTI, p!. 1.2.1, fig. l 0. to the cusp. Furthermore, in adult specimens of K v. 1998b Kockelella variabilis ichnusae Serpagli & Corradini - variabilis both latera! processes are branched and the CoRRADINI eta!., pl. 1.3.1, fig. 14. length/width ratio in K v. ichnusae is higher. Finally, 1998a Kockelella variabilis ichnusae Serpagli & Corradini - FERRETTI, CoRRADINI & SERPAGLI, pl. 2.2.1, fig. 16; pl. in lower view, the posterior process of K v. variabilis is 2.2.2, fig. 14. apparendy undifferentiated from the main part of the 1998 Kockelella variabilis Walliser- MANNIK & MALKOWSKI, pl. basai cavity, whereas in K v. ichnusae it is always 2, fig. 5. recognisable because the cavity narrows posteriorly. 1998 Kockelella aff. variabilis- MANNIK & MALKOWSKI, pl. 2, However, intermediate forms between K v. fig. l o. variabilis and K v. ichnusae have been observed in samples coming from the K v. variabilis and the Oz. Holotype- The specimen illustrated by Serpagli & exc. hamata Zones. Corradini (1998) o n P l. l, Fig. l a-c an d h ere The Pa element of K v. variabilis differs from the reillustrated on Pl. 4, fig. 5a-c; IPUM 25834. equivalent of K crassa in the shape of the basai cavity, which is usually less expanded and irregularly Paratypes (figured)- IPUM 25835-25839,27490- developed. Furthermore, in K v. variabilis latera! 27491. processes are always well developed and a ridge usually connects the cusp with the nearest denticle on the Locus typicus- Silius Io section, near Silius village, platform (no "unornamented areà' exists dose to the SE Sardinia, ltaly. biade). M ELEMENT. The M element of K v. variabilis never Stratum typicum- Level SIL lo 5. possesses an anterior process, differing, therefore, from the same elements of K a. sardoa and K maenniki. Derivatio nominis - From Ichnusa, the ancient Se ELEMENT. We believe that this element is much Greek name of Sardinia. more similar to Ligonodina salopia (sensu Walliser, 1964, but not to L. salopia sensu Rhodes, 1953), than to L. Diagnosis (after Serpagli & Corradini, 1998)-The silurica Branson & Mehl (sensu Walliser, 1957). stout Pa element is characterised by fused denticles anterior to the cusp, and by a wide asymmetrical Range- From the late K crassa Zone to the top of platform bordered by a rim; the inner side of the the A. ploeckensis Zone. platform is short and rounded, and bears a simple latera! process. The posterior process is arched downward and Studied materia! - 308 (+l questionable) Pa gendy deflected. elements from samples GA 2, FRU A, FRU O, FRU B, SIL Io l, SIL Io 2, SIL Io 3, SIL Io 4, SIL Io 5, SIL Io 6, Description- Pa ELEMENT. The Pa element is usually RMC O, RMC l, RMC lA, GALE BK 40, GALE robust and large in size. The anterior biade is relatively BK 23, GALE BK 8, SF 9, SF 12, SF BK 12, PF BK thick, long and straight, and bears nine to fourteen G, PF 9, PF 10, PF 10, PF O, PF l Q and PF llB. denticles. Anterior to the cusp, two to four denticles are fused together forming a crest (the number of fused 294 E. SERPAGLJ, C. CORRADINI denticles increases in largest specimens). The blade platform, that is bordered by the characteristic rim, ends anteriorly with three stout, high and discrete by the unbranched inner process and by the denticles followed by one or two very short denticles. occurrence of a crest on the anterior blade. In the largest specimens, these small denticles increase Few specimens of K v. ichnusae have a subtriangular in number (up to 5) and decrease in size towards the basal caviry like that of K stauros Barrick & Klapper, end of the blade, producing a serrated oudine on the which, however, has always a simple outer process. anterior margin. The specimen from New South Wales (Australia) The short posterior blade is arched downward and figured by Link & Druce (pl. 3, figs. 11, 12, 15, 16; gendy incurved. lt bears three to four stout, erect t ex t-fig. 21) possess most of the features of K v. ichnusae denticles, followed by a small one. (including fused denticles anterior to the cusp and fan- A wide asymmetrical platform is bordered by a rim. shaped ridge of the outer process denticles), except O n the inner side of the element the platform is short number of denticles on the short inner lateral process. and rounded, and bears a lateral process with one or two denti cles alligned perpendicularly to the blade. The Range- From the base of the Oz. exc. hamata Zone outer platform is better developed, has a polygonal to the middle part of the Poi. siluricus Zone. oudine and bears a complex process with three to eight discrete or closely spaced denticles, sometimes forming Studied material- 81 Pa elements from samples GA a fan-shaped ridge usually more or less parallel to the 3, FRU B, GCIU l, GCIU 3, SIL Io l, SIL Io 2, SIL Io blade. 3, SIL Io 4, SIL P 5, SIL Io 6, SIL Io 7, SIL Io 8, RMC The cusp is erect, only slighdy larger than adjacent l, RMC lB, RMC l C, SBF 5, GALE BK 8, GALE denticles. l t is usually connected to the closest denticles BK 13, PF lQ, PF llB, PF lH, FTM l, FTM 2, on the lateral processes by narrow ridges. FTM 2A and SAD 21. O ne side of the wide basal caviry is larger than the other one. The caviry extends as a narrow groove to the anterior and posterior ends of the main processes. CONCLUSIONS Pb, M, Sa, Sb and Se ELEMENTS. These are apparendy indistinguishable from the corresponding elements of The main results of the studies of the taxonomy K v. variabilis. and evolution of Kockelella are the following: l - The number of Kockelella taxa increases, changing Remarks- Pa ELEMENT. The most typical features from twelve to sixteen; of K v. ichnusae (robust blade, posterior process arched 2 - Both Kockelella variabilis an d K absidata have been downward and gendy deflected, wide asymmetrical subdivided into two subspecies; platform bordered by a rim, short and rounded inner 3 - The old problem of the recontruction of the K crassa platform with a simple process, fused denticles apparatus is finally solved; anteriorly to the cusp, and serrated outline of the 4 -The reconstruction of the phyletic relations within anterior margin) co-occur only in adult specimens. the genus Kockelella (which largely follows that one In juvenile specimens only some of these features are ofBarrick & Klapper, 1976) shows that three main present. Furthermore, in these specimens, the inner lineages, all originating from the common ancestor platform may be undenticulated. K ranuliformis, are recognisable (Text-fig. l); The Pa element of K v. ichnusae differs from that 5 - Kockelelfa patula and its possible descendants are of K v. variabilis, Walliser 1957 mainly by the wider still a problem, being difficult to place in our

EXPLANATION OF PLATE 7

Figs. 1-7 - Kockelella variabilis variabilis Walliser, 1957. l) IPUM 25855, sample PF llB ( Oz. exc. hamata Zone); upper view (a) and lower view (b) of Pa element; x60; 2) IPUM 25856, sample PF l Q (A . ploeckensis Zone); upper view (a) and lower view (b) of Pa element; x80; 3) IPUM 25854, sample SIL ro 3 (Oz. exc. hamata Zone); upper view ofPa element; x80; 4) IPUM 27494/1, sample PF llB (Oz. exc. hamata Zone); posterior view of Sb element; x55; 5) IPUM 27494/2, sample PF llB (Oz. exc. hamata Zone); inner-lateral view of Pb element; x55; 6) IPUM 27494/3, sample PF llB ( Oz. exc. hamata Zone); inner-lateral view of Se element; x60; 7) IPUM 27494/4, sample PF llB (Oz. exc. hamata Zone); inner-lateral view of M element; x66.

Figs. 8-9 - Kockelella stauros Barrick & Klapper, 1976. 8) IPUM 27474, sample GALE BK 18 (K crassa Zone); upper view (a) and lower view (b) ofPa element; x66; 9) IPUM 27475, sample SF BK 3 (K crassa Zone); upper view (a) and lower view (b) of Pa element; x66.

Fig. 10 - Kockelella ranuli(ormis (Walliser, 1964). IPUM 25862, sample ARG C (K ranuliformis Zone); upper view (a) and latera! view (b) ofPa efement; x80. E. SERPAGLL C. CORRADINL TAXONOMY AND EVOLUTION OF KOCKELELLA Pl. 7 296 E. SERPAGLI, C. CORRADINI

phyletic scheme; Perde Fogu (Ferretti et al., 1998a; fig. 2.2.1, p. 157) 6 - The K crassa stock up to date does not show a Argiola (Corradini et al., 1998a; fig. 3.3.1, p. 195). clear link to the main tree and therefore is left to Remarks on the other localities are as follows: open interpretation; Genna Arrela and Monte Fruccas: refer to Corradini & Olivieri 7 - Two main crises affected the Kockelella stock. The (1997, fìg. l); first one took piace during the late Oz. s. rhenana Riu Murru de Callus: this locality is about l Km SE of stop 4.1 of the ECOS VII- Sardinia Fie! d trip Guidebook (Ferretti et al., Zone and led to the extinction of K ranuliformis, 1998b, fìg. 4.1.1, p. 202); K latidentata, K corpulenta, K amsdeni, K cf stauros San Basilio Fenugu: this locality is about l Km E of stop l. l of sensu Bischoff, 1986, Kockelella sp. nov. A Klapfer the ECOS VII- Sardinia Field trip Guidebook (Ferretti et al., & Murphy, 1975 (sensu Bischoff, 1986), as wel as 1998c, fìg. 1.1.1, p. 97); K patu/a. The second crisis occurred just above the Galemmu, Sentiero Flumini and Corti Baccas: these outcrops are located in the Fluminimaggiore area: refer to the map in Fig. Wenlock-Ludlow boundary an d affected K stauros, 2.2.1 of the ECOS VII- Sardinia Field trip Guidebook (Ferretti Kockelella sp. nov. A Klapper & Murphy 1975, K et al., 1998a, p. 157); walliseri and K crassa; Funtanamare: village on the south-west coast, 2 Km South of 8 - The surviving taxa, K v. variabilis and K a. absidata, Nebida. Sant'Antonio Donigala: Sant'Antonio di -Donigala area, successfully evolved, producing descendants that South of Oristano; outcrops dose to Case Casti. reached the late Pol. siluricus Zone, when the whole lineage became to the end; 9 - The new species K crassa and K maenniki have good stratigraphic value, both being restricted to a short APPENDIX2

intervals of the Gorstian and of the Ludfordian, I NDEX OF THE REILLUSTRATED SPECIMENS respectively. With this papera generai synthesis of the whole Kockelella of Sardinia is presenred. It is, therefore, useful to show again fìgures of specimens reported o n the ECOS VII Sardinia Field-excursion AKNOWLEDGEMENTS Guide Book (Serpagli, ed., 1998).

The idea of the present revision arised during a scienrifìc visi t This paper ECOS VIISardinia Field-excursion guidebook by the senior author at the Department of Geology of Lund University. W e express our deep grati tute to J. Barrick (Texas Tech P!. l , fìg. l Corradini et al., 1998a, P!. 1.3.1, fìg. 16. University) no t only for the revision of the manuscript, but chiefly P!. L fìg. 5 Serpagli et al., 1998, P!. 1.2.1, fìg. 7. for the suggestion that "Oz." crassa Walliser joins, as Pb elemenr, P!. l, fìg. 8 Ferretti et al., 1998a, P!. 2.2.1, fìg. 5. "K" circaquadra Serpagli & Corradini in the apparatus of K crassa. P!. l, fìg. 11 Ferretti et al., 1998a, P!. 2.2.1, fig. 12. Discussions and exchange of opinions with L. Jeppsson (Lund P!. 2, fig. l Serpagli & Corradini, 1998, P!. l, fig. 6. University) and P. Mannik (Tallinn Technical University) greatly P!. 2, fìg. 2 Corradini et al., 1998a, P!. 1.3.1, fìg . 10. improved this paper. O.H. Walliser kindly provided camera lucida P!. 2, fig. 3 Corradini et al., 1998a, P!. 1.3.1, fìg. 12. drawings and pictures of some specimens from Cellon. Thanks P!. 2, fìg. 5 Ferretti et al., 1998a, P!. 2.2.2, fig. 12. are also due to M r. Claudio Genrilini for S.E.M. photographs and P!. 2, fig. 10 Serpagli & Corradini, 1998, P!. l, fig. l O. to Mr. Giancarlo Leonardi far graphical support. P!. 3, fig. 2 Serpagli & Corradini, 1998, P!. l, fìg. 4. Research funded by CNR and MURST granrs (40%, 60% P!. 3, fìg. 5 Serpagli & Corradini, 1998, P!. l, fìg. 7. and COFIN97, resp. E. Serpagli). P!. 3, fìg. 6 Ferretti et al., 1998a, P!. 2.2.1, fig. 15. This is a contribution to IGCP project 421 North Gondwana P!. 3, fìg. 7 Serpagli & Corradini, 1998, P!. l, fig. 3. Mid-Palaeozoic Bioevent !Biogeography Patterns in Relation to Crustal P!. 3, fìg. 8 Ferretti et al., 1998a, P!. 2.2.1, fig. 7. Dynamics. P!. 3, fìg. 9 Ferretti et al., 1998a, P!. 2.2.2, fig. 8. P!. 4, fìg. l Ferretti et al., 1998a, P!. 2.2.2, fig. 14. P!. 4, fìg. 3 Serpagli et al., 1998, P!. 1.2.1, fìg. 10. P!. 4, fìg. 5 Serpagli & Corradini, 1998, P!. l, fìg. l . P!. 4, fìg. 6 Ferretti et al., 1998a, P!. 2.2.1, fig. 16. APPENDIX l P!. 4, fìg. 7 Serpagli & Corradini, 1998, P!. l, fig. 2. P!. 5, fìg. l Ferretti et al., 1998a, P!. 2.2.2, fig. 16. REMARKS ON SAMPLE LOCATION. P!. 5, fìg. 2 Ferretti et al., 1998a, P!. 2.2.1, fig. 17. Locality abbreviations: P!. 5, fìg. 3 Serpagli et al., 1998, P!. 1.2.1, fìg. 13. SE Sardinia: GA=Genna Arrela, FRU=Monte Fruccas, P!. 5, fìg. 10 Corradini et al., 1998b, P!. 3.3.1, fìg. 4. 0 0 GCIU=Genna Ciuerciu, SIL I =Silius I , RMC=Riu Murru de Callus, SBF=San Basilio Fenugu; SW Sardinia (environs of Fluminimaggiore): GALE=Galemmu, APPENDIX3 CB Ill=Corti Baccas 3,d, PF=Perd'e Fogu, SF=Sentiero Flumini [samples SF 7, 8, 9, 12 from Serpagli, 1971]; SW Sardinia (other areas): ARG=Argiola, FTM=Funtanamare, During the restudy of the sections Silius Io and Genna Ciuerciu SAD=Sant'Antonio di Santadi-Donigala. (both in SE Sardinia) in connection to the preparation of the ECOS VII Field Trip Qune 1998), new samples were collected. For the detailed location of the localities visited during the ECOS Because the old sample numeration was already complex, we VII Sardina field trip refer to the Guide-book (Serpagli, ed., decided to replace i t with a new, more simple one. Therefore, a 1998): comparative chart of the numbers reported in the preliminary Genna Ciuerciu (Corradini et al., 1998b; fig. 1.3.1, p. 113), paper (Barca et al., 1995) and the new ones used in the ECOS VII Silius (Serpagli et al., 1998; fìg. 1.2.1, p. 105), Field trip Guidebook (Serpagli et al., 1998; Corradini et al., 1998b) TAXONOMY AND EVOLUTION OF KOCKELELLA 297 is presented below. The new numbers are also marked on the Formation, Centra! Tennessee: Journal of Paleonrology, 57 outcrops. (2): 20B-239. BARRJCK, J.E. & l

Zonation: Transactions of the Royal Society of Edinbourgh, SERPAGLI, E. (ed.), 1998, Sardinia Guide-book, ECOS VII: Giornale Earth Sciences, 88:91-114. di Geologia, 60, Spec. Issue: 212 pp. ]EPPSSON, L., VIIR'I., V & MANNIK, P., 1994, Silurian conodont- SERPAGLI, E. & CoRRWINI, C., 1998, New taxa of Kockelella based correlations between Gotland (Sweden) and Saaremaa (Conodonta) from Late Wenlock-Ludlow (Silurian) ofSardinia. (Estonia): Geologica! Magazine, 131 (2): 201-218. In Serpagli, E. (ed.), Sardinia Guide-book, ECOS VII: Giornale l