Goniagnostus Howell and. Lejopyge Corda from. Revision of species of. Australia (Agnostida, Cambrian) Phylogeny JOHN R. LAURIE

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1 Revision of species of Lejopyge Corda from Cambrian) JOHN R. LAURIE Goniagnostus Howell and Australia (Agnostida, LAURIE, J. R., 1989:08:28. Revision of species of Goniagnostus Howell and Lejopyge Corda from Australia (Agnostida, Cambrian). A Icheringa 13, ISSN Relationships of Australian species of the agnostoid genera Goniagnostus and Lejopyge are discussed and some revisions made. Goniagnostus consists of G. (Goniagnostus), containing G. (G.) nathorsti and G. (G.) scarabaeus; G. (Criotypus) containing G. (C.) oxytorus and G.(C.) lemniscatus; and G. (Allobodochus) containing G. (A.) fumicola and G. (A.) spiniger. Representatives of Lejopyge are L. armata, L. laevigata, L. catva, L. dubium, L. multifora and L. cosfordae. Goniagnostus is considered to have evolved from Triplagnostus (Triplagnostus) and Lejopyge possibly from Onymagnostus. J.R. Laurie, Division of Continental Geology, Bureau of Mineral Resources, GPO Box 378, Canberra, ACT, 2601, Australia," received 13 July Keywords: Agnostida, Trilobita, revision, Middle Cambrian, Australia. THIS PAPER revises Goniagnostus and Lejopyge, two of the three genera of Ptychagnostinae Kobayashi 1939 not discussed in a previous paper (Laurie, 1988). Goniagnostus Howell 1935 has often been used with reservation (Whitehouse, 1939, p. 257; Westergaard, 1946, p: 80). Opik (1961, p. 81, 1967, p. 90) considered it a subgenus of Ptychagnostus but later (Opik, 1979, p. 143) accorded it generic status and subdivided it into three subgenera. Lejopyge Corda 1847 has usually been restricted to effaced species; the main focus of study was aimed at establishing their relationships to en grande tenue forms (Kobayashi, 1937, p. 439; 1939, p. 128). Such relationships were suggested by Westergaard (1946, p. 75) though he retained similar en grande tenue forms in Ptychagnostus (Triplagnostus). Opik (1979, p. 157) was the first to include en grande tenue forms with the effaced species. Phylogeny Based on conservative or slowly changing morphological features in other lineages (see 0311/5518/89/ $3.00 AAP Robison, 1984, p. 11; Laurie, 1988)several assumptions of probable morphological properties of ancestors can be made based on the most parsimonious explanation. Some of these properties are discussed below. Although later species of Goniagnostus do not have arcuate scrobicules, in the earliest species assigned to G. (Criotypus) they are very well developed. Furthermore, Goniagnostus possesses a well developed median node near the midlength of the posterior pygidial axial lobe, elongate basal lobes, the glabellar node in the extreme posterior of the glabella and a slight to moderate taper of the posterior glabellar lobe (for definition see Laurie, 1988), so it is probable the immediate ancestor possessed most, if not all of these features as well. There are only two genera of the necessary age within the Ptychagnostinae which even vaguely fit these criteria; namely T. (Triplagnostus) and Pentagnostus. Like G. (Criotypus), T. (Triplagnostus) has, although rarely impressed, arcuate scrobicules, elongate basal lobes, a well developed node at about the midlength of the posterior pygidial axial lobe, a posteriorly located glabellar node and a moderately tapering posterior glabellar lobe. Pentagnostus, on the other hand, while having arcuate scrobicules and a slightly tapering

2 176 JOHN R. LAURIE ALCHERINGA posterior glabellar lobe, has only slightly elongate basal lobes and a more forwardly located glabellar node and lacks the median node on the posterior pygidial axial lobe. Therefore, the probable ancestor of the Goniagnostus lineage was a species of T. (Triplagnostus). In his diagram of inferred phylogeny of the Ptychagnostinae, Robison (1984, p. 11) proposed a tentative derivation of the earliest species of Lejopyge, L. lundgreni, from Ptychagnostus intermedius [ = Zeteagnostus scarifatus (Opik), Laurie, 1988]. This I believe to be unlikely as Z. scarifatus has elongate basal lobes and a small node on the second pygidial axial segment which deflects the F2 furrow little or not at all, whereas earlier species of Lejopyge, such as L. lundgreni (Tullberg) have a large node on the second pygidial axial segment which strongly deflects the F2 furrow (see Westergaard, 1946, pl. 10, fig.24; Robison, 1984, fig.27-2, 4, 7, fig. 28-4, 5). Also, all species of Lejopyge have short basal lobes. Like Lejopyge, some species of Onymagnostus have short basal lobes and a large node on the second pygidial axial segment which strongly deflects the F2 furrow. Therefore I tentatively suggest that an origin for Lejopyge lies somewhere within Onymagnostus rather than Zeteagnostus. Material Figured specimens are housed in the Commonwealth Palaeontological Collection (prefix CPC) at the Bureau of Mineral Resources, Canberra or are from the Swedish.Geological Survey (prefix SGU). Unless otherwise indicated, illustrated specimens were collected by the late A. A. Opik mostly from the Georgina Basin of western Queensland and eastern Northern Territory. Stratigraphic and geographic data for these localities are given by Opik (1979, p. 172), except for D15, D18, D26 (0pik, 1961, p ) and G9, G131 and G417 (Opik, 1967, p. 28). Terminology I follow the terminology of Opik (1961, 1967, 1979) except for the notation of intra-axial furrows (F1, F2, F3) which are used as defined by Robison (1982, p. 134). Other details of terminology are explained by Laurie (1988). Systematics Goniagnostus Howell 1935 Type species. Agnostus nathorsti Br6gger Diagnosis. Exoskeleton of moderate to large size, en grande tenue with axial furrows strongly impressed and median preglabellar furrow well developed, usually scrobiculate; prosopon smooth or finely to coarsely pustulose; spinose with an axial spine on the posterior thoracic segment and a pair of pygidial marginal spines, with or without cephalic spines, an occipital spine and fulcral spines on the posterior thoracic segment. Anterior glabellar lobe low, subtriangular; posterior glabellar lobe broad, very strongly convex in posterior half, with lateral glabellar furrows very well developed, axial glabellar node located posteriorly, behind anterior extremities of basal lobes. Basal lobes elongate, divided or entire, anterior extremities indistinct, associated with a well developed appendiferal pit. Pygidial axis long with spine on middle lobe strongly deflecting posterior transverse furrow rearward; posterior lobe long, pyriform with strong tubercle near midlength, centred on a variably developed rosette. Median postaxial furrow well developed. Distribution. L. lundgreni-g, nathorsti to L. laevigata Zone, Sweden, Norway and Denmark; A. atavus to E. eretes Zone, Queensland and Northern Territory; A. cassis or P. agra Zone, Tasmania; P. jimaensis-c. tuma Zone, Hunan and Guizhou; L. laevigata Zone, Zhejiang; upper P. davidis Zone and L. laevigata Zone, England; P. hicksi Zone, New Brunswick and Newfoundland; G. nathorsti to lower K. simplex Zone, Kazakhstan and Uzbekistan; H. brevifrons beds, Maya stage, Turkestan; A. henrici Zone, A. limbataeformis Zone and L. laevigata-a, truncata Zone, Siberian Platform; Middle Cambrian, Qinghai, Altay- Sayan and Argentina.

3 ALCHERINGA AUSTRALIAN AGNOSTIDS 177 Remarks. Opik (1979, p ) described ten Middle Cambrian species of Goniagnostus in three subgenera, G.(Goniagnostus), G. (Criotypus) and G.(Allobodochus); G. (Criotypus) has a less attenuated posterior pygidial lobe with a shallow transverse depression and arcuate scrobicules; G. (Allobodochus) has furrows separating the outer glabella from the midmost glabella, a very well developed rosette and a granulose test. Although I at first presumed these features to be part of a continuous range of variation, close examination of the Australian material and published work on the genus has led me to conclude that this is not so. Some species of Goniagnostus have a pattern of scrobiculation which differs discretely from that of the genotype. These, which Opik (1979) assigned to G.(Criotypus), have short radial scrobicules across the anterior margin of the cephalic acrolobe and a pair of well developed arcuate scrobicules which envelop the glabellar anterior. Conversely, the genotype and related species have a set of alternating long and short radial scrobicules but lack the arcuate scrobicules of G. (Criotypus). G. (C.) mitigatus Opik 1979 lacks arcuate scrobicules and is herein assigned to G.(Goniagnostus) (see discussion of G.(G.) scarabaeus). In G.(Goniagnostus) and G. (Criotypus) the transverse depression on the posterior pygidial axial lobe is absent or weakly developed whereas in G. (Allobodochus) this depression and the associated median tubercle form a very well developed rosette, giving the pygidial axis a quadrilobate appearance. Also, both of the Australian species assignable to G. (Allobodochus) have granulose pygidial pleurae. Goniagnostus (Goniagnostus) Howell 1935 Diagnosis. Cephalon without arcuate scrobicules but with alternating long and short radial scrobicules round the anterior portion of the acrolobe. Posterior lobe of pygidial axis with transverse depression absent to weakly developed. Distribution. L. lundgreni-g, nathorsti to S. brachymetopa Zone, Sweden, Norway and Denmark; P. punctuosus to G. nathorsti Zone, Queensland;? upper P. davidis Zone, England; P. hieksi Zone, New Brunswick and Newfoundland; H. brevifrons beds, Maya stage, Turkestan; A. henrici to L. laevigata- A. truncata Zone, Maya stage, Siberian Platform; Middle Cambrian, Qinghai and Argentina. Goniagnostus (Goniagnostus) nathorsti (Br6gger 1878) (Fig. 1) 1878 Agnostus nathorsti BrOgger, p. 68, pl. 5, fig Goniagnostus nathorsti (Br6gger); Howell, p. 13, figs 1-2.? 1939 Goniagnostus cf. nathorsti (Br6gger); Whitehouse, p. 259, pl. 25, fig Goniagnostus nathorsti (Br6gger); Westergaard, p. 81, pl. 12, figs Coniagnostus nathorsti (Br6gger); Pokrovskaya, p. 62, pl. 5, figs ?1960 Goniagnostus datongensis Zhu, p. 70, pl. 1, figs 1, 2 (not fig.3). not 1961 Ptychagnostus (Goniagnostus) sp. aff. nathorsti (Br6gger); Opik, p. 84, pl. 21, fig. 1.? 1965 Goniagnostus datongensis Zhu; Lu et al., p , pl. 2, figs 21, 22 (not fig. 23) Goniagnostus nathorsti (Brogger); Rozova et al., p. 146, pl. 19, figs 5, Goniagnostus (Goniagnostus) nathorsti (Br6gger); Opik, p. 150, pl. 60, figs 1-5; pl. 61, figs 1, Goniagnostus (Goniagnostus) nathorsti intersertus Opik, p. 153, pl. 61, fig. 7. Diagnosis. Cephalic spines absent, pygidial marginal spines short, broad. Remarks. Australian representatives have been adequately described and illustrated by Opik (1979) but are here re-illustrated for comparative purposes. G. datongensis Zhu 1960 is very tentatively included in the synonymy of G. (G.) nathorsti. The two cephala (Zhu, 1960, pl. 1, figs 1, 2; Lu etal., 1965, pl. 2, figs 21, 22) may belong to G. (Goniagnostus) or G. (Allobodochus), the development of the furrows in the posterior glabellar lobe giving no clear indication. The pygidium (Zhu, 1960, fig. 3; Lu et al., 1965, fig. 23) has no transverse furrows on the pygidial axis and almost certainly belongs to Doryagnostus incertus (Br6gger 1878). Ptychagnostus (Goniagnostus) sp. aff. nathorsti (Opik, 1961, pl. 21, fig. 1) is a finely

4 178 JOHN R. LAURIE ALCHERINGA pustulose pygidium with well developed rosette and therefore does not belong to G. (Goniagnostus). Opik (1979, p. 157) tentatively reassigned that specimen to G. Fig. 1. Goniagnostus (Goniagnostus) nathorsti (Br6gger). All x 8, all stereopairs, all t:rom iocaiity M57, aii complete shields, A, B, C natural moulds, D, E, F latex moulds. A, CPC B, CPC C, CPC D, CPC E, CPC F, CPC25890.

5 ALCHERINGA AUSTRALIAN AGNOSTIDS 179 (A llobodochus) spiniger (Westergaard 1931). It is herein assigned to this latter species with confidence. Goniagnostus (Goniagnoslus) scarabaeus Whitehouse 1939 (Fig. 2) 1939 Goniagnostus scarabaeus Whitehouse, p. 260, pl. 25, fig. 19.? 1958 Goniagnostus Iongispinus Pokrovskaya, p , pl. 5, figs Goniagnostus longispinus var. latirhachis Pokrovskaya, p. 70, pl. 5, figs Ptychagnostus (Goniagnostus) scarabaeus Whitehouse; Hill, Playford & Woods, pl. 9, fig Goniagnostus (Goniagnostus) scarabaeus Whitehouse; Opik, p. 153, pl. 61, figs 2, 8; pl. 62, figs 1, Goniagnostus (Goniagnostus) verus Opik, p. 155, pl. 62, figs 3-5; pl. 63, figs 1, 2.? 1979 Goniagnostus (Criotypus) mitigatus Opik, p. 147, pl. 57, fig. 3. Diagnosis. Cephalic spines long, pygidial marginal spines commonly of moderate length. Pygidial pleurae weakly pustulose in some specimens. Remarks. This species is very similar to G. (G.) nathorsti but differs in having long cephalic spines, usually longer pygidial marginal spines and a usually narrower pygidial axis. Goniagnostus longispinus Pokrovskaya 1958 is tentatively placed in G.(G.) scarabaeus. In comparing G. longispinus with G. scarabaeus, Pokrovskaya (1958, p ) noted that the latter had a narrower glabella, larger basal lobes, a shorter posterior pygidial axial segment and lacked both the cephalic and the pustulose prosopon on the former. Comparison of illustrated specimens of G. longispinus with the holotype of G.(G.) scarabaeus show that the differences between them in glabellar width, basal lobe size and posterior pygidial axial lobe length are very slight. Such minor differences are dubious criteria for specific differentiation within the agnostids and can easily be accommodated within the range of intraspecific variation. Furthermore, in determining the presence or absence in G.(G.) scarabaeus of cephalic spines, the holotype shows damaged bases of what may have been large spines, while specimens illustrated by Opik (1979, pl. 62, figs 2, 3) show well developed cephalic spines. It therefore seems likely that the species is characterised by long cephalic spines, as is G. longispinus. The development of the pustules on the pygidial pleurae of G. longispinus is unclear in the illustrations given by Pokrovskaya (1958, pl. 5, figs 1-8) but appears variable. G. scarabaeus usually has smooth pygidial pleurae but occasional specimens show a weakly pustulose prosopon. Another Australian form, G.(G.) verus, coincidentally found only in association with G.(G.) scarabaeus, has a granular or finely pustulose prosopon. G. (G.) verus is probably a synonym of G. (G.) scarabaeus, representing the more highly ornamented end-member of a continuum of variation. If such a variation exists within G.(G.) scarabaeus then G. longispinus may well be synonymous. G. (Criotypus) mitigatus is known from one well preserved cephalon (Opik, 1979, pl. 57, fig. 3) that does not have arcuate scrobicules, but has short anterolaterally directed scrobicules extending from the front of the glabella which, in association with the curved medial extremities of two of the longer radial scrobicules gives the specimen the appearance of having incipient (or remnant) arcuate scrobicules. Opik (1979, p. 147) believed the arcuate scrobicules of G.(C.) mitigatus to be vestigial. I disagree, believing that it is only a fortuitous juxtaposition of other scrobicules which give that impression. In other species assigned to G. (Criotypus) the distal two-thirds of the arcuate scrobicules are subparallel to the axial furrow bounding the anterior glabellar lobe, with the area enclosed by the axial furrow and the arcuate scrobicule being much longer than wide, having its long axis also subparallel to the axial furrow. In G.(C.) mitigatus the distal portion of the 'vestigial arcuate scrobicules' are continuous with a pair of the longer radial scrobicules such that the whole has a distinct rearward kink. Similarly kinked, long, radial scrobicules can be seen in occasional specimens of G(G.) nathorsti (see Opik, 1979, pl. 60, fig. 3, pl. 61, fig. 1) and G.(G.)scarabaeus (see Opik, 1979, pl. 62, fig. 2). In G.(C.) mitigatus the proximal portion of the 'vestigial arcuate scrobicules' are concave forwards rather than concave rearwards as is the case in all other specimens

6 180 JOHN R. LAURIE ALCHERINGA

7 ALCHERINGA AUSTRALIAN AGNOSTIDS 181 assignable to G.(Criotypus). However in one specimen of G.(C.) lemniscatus (Opik, 1979, pl. 58, fig. 8) in the proximal portion of the right arcuate scrobicule there is a bifurcation with the posterior branch forming the arcuate scrobicule and the anterior one, which is concave forwards, extending only a short distance from the bifurcation. I think it is this scrobicule which is so clearly developed in G.(C.) mitigatus. Furthermore, the area (almost) enclosed by these 'vestigial arcuate scrobicules' is of quite a different shape to that of other species assigned to G.(Criotypus), being approximately equidimensional. The above, coupled with the presence of long cephalic spines, is considered reason enough to tentatively include this specimen in the synonymy of G. (G.) scarabaeus. Goniagnostus (Criotypus) Opik 1979 Type species. Goniagnostus (Criotypus) oxytorus Opik Diagnosis. Cephalon with well developed arcuate scrobicules with concomitant reduction in length of radial scrobicules around anterior margin of acrolobe. Posterior lobe of pygidial axis with transverse depression absent, or rarely very weakly developed. Distribution. A. atavus and E. opimus Zones, Floran stage, Queensland. Goniagnostns (Criotypus) oxytorus Opik 1979 (Fig. 3A) 1979 Goniagnostus (Criotypus) oxytorus Opik, p. 145, pl. 57, figs 1, 2. Diagnosis. Exoskeleton of moderate size, cephalic spines long. Thorax with axial spine and fulcral spines on posterior segment. Pygidium with long marginal spines and with pustulose prosopon on pleural lobes. Remarks. This species is known only from one complete specimen which is found in association with both G. (C.) lemniscatus Opik and G.(C.)paenerugatus Opik. It is sufficiently different in its spinosity and prosopon to warrant retention of the specific name, however, because of its rarity no indication of the variation within the species can be gleaned. Goniagnostus (Criotypus) lemniscatus Opik 1979 (Fig. 3B-K) 1979 Goniagnostus (Criotypus) lemniscatus 0pik, p. 147, pl. 58, figs 1-8; pl. 59, fig Goniagnostus (Criotypus) sp. nov. aff. lemniscatus ()pik, p. 149, pl. 59, figs 3, (?) Goniagnostus (Criotypus) paenerugatus Opik, p. 149, pl. 45, fig. 5, pl. 59, figs 4-6. Diagnosis. Exoskeleton large, cephalic spines absent. Thorax with axial spine but lacking fulcral spines on posterior segment. Pygidium with short marginal spines, prosopon smooth. Remarks. This species is characterised by its large size, its lack of cephalic and thoracic fulcral spines and its smooth prosopon, by which it is easily differentiated from G.(C.) oxytorus Opik. The specimens referred to G.(C.) sp. nov. aff. lemniscatus by Opik (1979, pl. 59, figs 2, 3) are considerably smaller than the largest specimens of G.(C.) lemniscatus, and as at least one of the illustrated specimens (fig.3) is found associated with it, they are believed to represent early moults of that species. G. (C.) paenerugatus ()pik is represented by cephala of moderate size which, according to Opik (1979, p. 149) have weak scrobiculation, a trigonal glabella, divided basal lobes and lack cephalic spines. Opik (1979) differentiates this species from G.(C.) lemniscatus by its Fig. 2. Goniagnostus (Goniagnostus) scarabaeus Whitehouse. All 8, all stereopairs except G, all natural moulds. A, complete shield from M247, CPC B, complete shield from M462, CPC C, complete shield from M195, CPC D, complete shield from M195, illustrated as holotype of G.(G.) verus by Opik (1979, pl. 62, fig. 3), CPC E, cephalon from M195, illustrated as specimen of G.(G.) verus by Opik (1979, pl. 63, fig. 2), CPC F, cephalon from M191a tentatively assigned to this species, illustrated as holotype and only specimen of G.(Criotypus) mitigatus by Opik (1979, pl. 57, fig. 3), CPC G, small whole shield from M462, CPC25907.

8 182 JOHN R. LAURIE ALCHERINGA weaker scrobiculation and different glabellar shape. The former of these two differences can be cast aside by observing the considerable variation in degree of scrobiculation within G. (C.)lemniscatus (compare pl. 58, fig. 1 with figs 2 and 3, Opik, 1979). The latter difference is probably an artefact of the medium of preservation, with the type lot of G.(C.) Fig. 3. Goniagnostus (Criotypus). All x 8, all natural moulds. A, G.(Criotypus) oxytorus t~pik 1979, holotype flattened complete shield from M425, CPC B-K, G.(Criotypus) lemniscatus Opik B, stereopair of cephalon from M150, CPC C, pygidium from M176, CPC D. stereopair of cephalon from MI50, CPC E, compressed cephalon from M412, tentatively assigned to this species, originally illustrated as G.(C.) sp. nov. aff. lemniscatus by Opik (1979, pl. 59, fig. 3), CPC F, holotype flattened cephalon and anterior thoracic segment from M176, CPC G, flattened cephalon with damaged posterior margin from M176, CPC H, flattened cephalon associated with CPC14312 from M176. I, cephalon from M176, CPC J, pygidium from M 176, CPC K, pygidium from M 176, also numbered CPC (see fig. 3C), both having been closely associated on the same handspecimen and only given one number by Opik (1979, pl. 58, fig. 5).

9 ALCHERINGA AUSTRALIAN AGNOSTIDS 183 lemniscatus being well preserved and only slightly compressed in a siltstone, whereas the holotype of G.(C.) paenerugatus has a distorted glabella and is less well preserved and more strongly compressed in a finer siltstone. Such differences in preservation make minor variations in glabellar shape a doubtful criterion for the separation of species. As a consequence G.(C.) paenerugatus is tentatively placed in synonymy with G.(C.) lemniscatus. A similar conclusion with respect to preservation effects has been reached pertaining to the validity of Opik's (1979) subgenus Triplagnostus (Aristarius), a discussion of which is given by Laurie (1988). Goniagnostus (Allobodochus) Opik 1979 Type species. Ptychagnostus (Goniagnostus) fumicola Opik Diagnosis. Cephalon without arcuate scrobicules. Glabella with very strongly developed lateral furrows, commonly with the midmost glabella separated from the outer glabella by weak longitudinal (exsag.) furrows. Pygidial axis with very well developed rosette in posterior lobe. Distribution. A. cassis to E. eretes Zone, Queensland and Tasmania; L. laevigata Zone, Sweden and England;?G. nathorsti Zone,?L. armata Zone, upper L. laevigata Zone and Fig. 4. Goniagnostus (Allobodochus)fumicola Opik. All x 8 except E, x 9; all natural moulds except F, latex; all stereopairs except E; all from locality G9 except C, G417. A, partial cephalon, CPC3599. B, pygidium, CPC5840. C, silicified small pygidium, illustrated as holotype of Ptychagnostus (Goniagnostus) nodibundus Opik (1967, pl. 57, fig. 3), CPC5841. D, partial cephalon, CPC3601. E, F, holotype pygidium, CPC3598.

10 184 JOHN R. LAURIE ALCHERINGA Fig. 5. Goniagnostus (Allobodochus) spiniger (Westergaard). All 8, all flattened in shale, all from Karlsfors, Vastergotland. A, pygidium, illustrated by Westergaard (1946, pl. 12, fig. 19), SGU4964. B, holotype cephalon, illustrated by Westergaard (1946, pl. 12, fig. 18), SGU4963. C, D, damaged specimens on same handspecimen as SGU4964, but unnumbered. C, cephalon. D, pygidium. lower K. simplex Zone, Lesser Karatau, USSR; P. jimaensis-c, tuma Zone, Hunan and Guizhou; L. laevigata Zone, Zhejiang. Remarks. See remarks on Goniagnostus. Goniagnostus (Allobodochus) fumicola Opik 1961 (Fig. 4) 1961 Ptychagnostus (Goniagnostus) fumicola Opik, p. 81, pl. 20, figs 14a-17 (not pl. 21, fig. 2) Ptychagnostus (Goniagnostus)fumicola Opik, p. 91, pl. 57, fig. 2 (not fig. 1) Ptychagnostus (Goniagnostus) nodibundus Opik, p. 92, pl. 57, figs Goniagnostus venustus Zhou & Yang; Zhou el al., p. 112, pl. 36, figs Goniagnostus venustus Zhou & Yang; Yang, p. 22, pl. 1, figs Ptychagnostus (Goniagnostus) fumicola ()pik; Rushton, p. 261, pl. 25, figs 1, Goniagnostusfumicola Opik; Ergaliev, p. 73, pl. 2, figs l, Goniagnostusfumicola Opik; Liu, p. 291, pi. 207, figs 3, Goniagnostus venustus Zhou & Yang; Liu, p. 291, pl. 207, figs 11, Ptychagnostus atavus (Tullberg); Liu, p. 292, pl. 210, figs 8, 9. Diagnosis. Exoskeleton of moderate to large size, probably with well developed cephalic spines. Pleural lobes of cephalon weakly but coarsely pustulose. Pygidium with well developed, elongate marginal spines, pleural lobes strongly and coarsely pustulose. Remarks. In his original description of this species Opik (1961, p ) noted that the cephalic spines were 'long, straight and divergent' and gave a reconstruction (Opik, 1961, fig.28) supposed to have been made from the illustrated specimens which supported this assertion. Examination of the type lot of specimens which were illustrated by Opik shows that no cephalic spines are preserved. The only indication of their degree of development can be seen in Opik's (1961) fig. 15, plate 20 in which a broken spine base is present, however their length cannot be determined. In a later work, Opik (1967, p. 92, pl. 57, figs 3, 4) described a new species, Ptychagnostus (Goniagnostus) nodibundus based on a few very poorly preserved, silicified specimens. He differentiated this species from P.(G.)fumicola by its coarser pustules on the pygidial pleurae and by its convex glabellar flanks. The pygidial prosopon of P. (G.) nodibundus does appear much coarser than that of P. (G.).f.umicola as illustrated in this later work by Opik (1967, pl. 57, fig. 2) but the difference is not as pronounced when comparison is made with

11 ALCHERINGA AUSTRALIAN AGNOSTIDS 185 the type lot of P.(G.) fumicola (see Opik, 1961, pl. 20, fig. 14a, b). The difference between the two species from the later work is further exaggerated by the way the ammonium chloride coating has been applied to the P. (G.)fumicola pygidium. This coating is relatively light, giving the impression that the pustules are small and widely spaced, whereas that on the P.(G.) nodibundus pygidium is heavier and more evenly distributed over the pustules showing them to be large, rounded and closely spaced. Consequently, P. (G.) nodibundus is placed in synonymy with G.(A.)fumicola. A further complication exists in that two of the pygidia assigned to P.(G.)fumicola by Opik (1961, pl. 21, fig. 2; 1967, pl. 57, fig. 1) do not possess the coarse pustulose ornament characterising the holotype of the species. Rather, they have a finely pustulose ornament with many of the pustules coalescing such that an almost reticulate pattern is formed. This pattern is characteristic of G. (A.) spiniger (Westergaard), and these specimens are therefore assigned to that species. The species Goniagnostus venustus was compared closely with G. (A). fumicola (Opik) by Zhou & Yang (in Yang, 1978) but they differentiated the latter by its wider axial lobe and by the prosopon consisting of small tubercles rather than 'blister-like' protrusions. The width of the axis in any species of agnostid is always a variable feature and the slight difference in that parameter between the specimens of G. venustus and G.(A.) fumicola is of doubtful taxonomic value. Regarding the tuberculation in G. (A.)fumicola, it has been noted above that the appearance of the prosopon as consisting of widely spaced, small Fig. 6. Goniagnostus (Allobodochus) spiniger (Westergaard). All 8, all latex moulds except B and E, natural moulds, all stereopairs, all from locality T87 except A, D18. A, partial pygidium, CPC3604. B, partial cephalon, CPC C, E, cephalon, CPC D, partial pygidium, CPC14344.

12 186 JOHN R. LAURIE ALCHERINGA tubercles is exaggerated by the style of coating of the specimen, therefore, any such minor variation in the prosopon is considered too slight to warrant specific recognition. Goniagnostus (Allobodochus) (Westergaard 1931) (Figs 5, 6) spiniger 1946 Goniagnostus spiniger (Westergaard); Westergaard (in Lundquist et al.), p. 82, pl. 12, figs 18, Ptychagnostus (Goniagnostus) fumicola Opik, pl. 21, fig. 2 only Ptychagnostus (Goniagnostus) sp. aff. nathorsti (Br6gger); Opik, p. 84, pl. 21, fig Goniagnostus cf. longispinus Pokrovskaya; Wang et al, p. 28, pl. 3, figs 1, Goniagnostus cf. longispinus Pokrovskaya; Lu et al., p. 34, pl. 2, figs 24, Ptychagnostus (Goniagnostus)fumicola Opik, pl. 57, fig. 1 only Goniagnostus nathorsti (Brogger); Hairullina, p. 36, pl. 1, figs 13, Ptychagnostus (Goniagnostus) buckleyi Jago, p. 153, pl. 23, figs Goniagnostus bicavus Zhou; Zhou et al., p. 112, pl. 36, figs 25, Goniagnostus nathorsti (Br6gger); Yang, p. 21, pl. 1, figs 3, Goniagnostus (Allobodochus) spiniger (Westergaard); Opik, p. 156, pl. 63, figs 3-8.?1980 Goniagnostus nathorsti (Br6gger); Ergaliev, p. 73, pl. 2, figs 1, 2. Diagnosis. Exoskeleton of moderate to large size, cephalon with well developed cephalic spines and with pleural lobes weakly and finely pustulose. Pygidium with well developed, elongate marginal spines and with pleural lobes covered by fine pustules, many of which coalesce to form an almost reticulate prosopon. Remarks. The specimen referred to Ptychagnostus (Goniagnostus) sp. aff. nathorsti by Opik (1961, pl. 21, fig. 1) as discussed above has a distinct rosette and finely pustulose pygidial pleurae unlike G. (G.) nathorsti, an error more recently noted by t3pik (1979, p. 157) who then assigned that specimen (and others) to G.(A.) spiniger Westergaard. Earlier, however, Opik (1961, p. 82) stated that the prosopon of G.(A.) spiniger was smooth, although Westergaard (1946) makes no mention of surface texture in his too brief description and little can be gleaned from his single illustration of a pygidium. Examination of the type lot of specimens of G. spiniger (Westergaard) by me has shown that the pygidium (Westergaard, 1946, pl. 12, fig. 19) has a poorly preserved, finely pustulose prosopon on the pleurae. Specimens associated and undoubtedly conspecific with the type lot show this pustulose prosopon much more clearly. Two groups of specimens referred to G.(G.) nathorsti (see Hairullina, 1973, and Yang, 1978 in synonymy) belong to this species. Both groups have the finely pustulose prosopon on the pygidial pleurae coupled with a very well developed rosette, a combination characteristic of G. (A.) buckleyi. One further group of specimens referred to G.(G.) nathorsti (see Ergaliev, 1980, in synonymy above) may also belong in this species. They comprise two cephala which have weak exsagittal furrows subdividing the glabella and are therefore almost certainly members of G.(Allobodochus). Unlike G.(A.) fumicola there is no coarse pustulose prosopon on these cephala so they are tentatively assigned to G.(A.) spiniger. Goniagnostus bicavus Zhou was initially compared with G.(G.) nathorsti but it has a posterior glabellar lobe subdivided by weak exsagittal furrows, and a pygidium with a strongly developed rosette, rather large marginal spines and a finely pustulose pleural prosopon having a vaguely reticulate appearance and therefore should be included in the synonymy of G. (A.) spiniger. Similar comments can be made about the Chinese specimens referred to Goniagnostus cf. longispinus Pokrovskaya by Wang et al. (1964) and Lu and others (1965). They are like the latter species in having a similar spinosity and a fine, pustulose prosopon on the pygidial pleurae but have a well developed rosette and a posterior glabellar lobe subdivided by exsagittal furrows and almost certainly belong to G.(A.) spiniger. Lejopyge Corda in Hawle & Corda Miagnostus Jaekel 1958 Pseudophalacroma Pokrovskaya Type species. Battus laevigatus Dalman 1828 Diagnosis. Exoskeleton of moderate to large size, strongly convex, en grande tenue to

13 ALCHERINGA AUSTRALIAN AGNOSTIDS 187 Fig. 7. Lejopyge armata (Linnarsson). All 8, all natural moulds, all stereopairs. A, cephalon from W36, CPC B, pygidium from D15, CPC3615. C, cel~halon from D26, CPC3612. D, pygidium from D15, CPC3614. E, pygidium and parts of both thoracic segments from W36, on counterpart of specimen illustrated in Figure 7A and given same number, CPC F, small pygidium from D26, CPC3616, G, small pygidium from D26, CPC3613. almost completely effaced, usually nonscrobiculate; with smooth prosopon; nonspinose or with cephalic spines, axial and fulcral spines on posterior thoracic segment and pygidial marginal spines. Cephalic border very narrow. Anterior glabellar lobe narrow, subtriangular; posterior glabellar lobe strongly expanded with lateral glabellar furrows usually absent, axial glabellar node at or posterior to lobe midlength. Basal lobes short, simple. Pygidial axis with small node on middle lobe, slightly deflecting posterior transverse furrow rearward. Posterior lobe long, acuminate or narrowly rounded posteriorly. Distribution. Upper P. punctuosus to L. laevigata Zone, Sweden, Norway and Denmark; P. punctuosus to C. quasivespa Zone, Queensland and Tasmania; P. forchhammeri Zone, England; G. nathorsti to L. laevigata Zone, Lesser Karatau, Kazakhstan; H. brevifrons beds, Turkestan Range, Kazakhstan and Uzbekistan; A. henrici to L. laevigata-a, truncata Zone, Siberian Platform; L. laevigata Zone, Zhejiang, Hunan and Guizhou; Paramphoton Zone, Hunan; Bolaspidella Zone, New York, Utah and Nevada; Middle Cambrian, Qinghai, Alaska and Newfoundland;?Upper Cambrian, Argentina. Remarks. Both Robison (1984, p ) and Opik (1961, p. 86) place Phoidagnostus Whitehouse in synonymy with Lejopyge. However, I have examined the holotype cephalon of Phoidagnostus limbatus, the type

14 188 JOHN R. LAURIE ALCHERINGA species, and record that it has a border of moderate width, a weak preglabellar median furrow, short and very broad basal lobes extending far from the posterior glabellar lobe, as in "Agnostus" bituberculatus Angelin, and an elongate median glabellar node located well forward, at about the midlength of the cephalon. Thus Phoidagnostus is clearly not a synonym of Lejopyge. The concept of Lejopyge adopted here is largely that of Opik (1979, p ) with modifications introduced by Robison (1984, p ). Lejopyge armata (Linnarsson 1869) (Fig. 7) 1869 Agnostus laevigatus var. armata Linnarsson, p. 82, pl. 2, figs 58, Lejopyge laevigata armata (Linnarsson); Westergaard, p. 89, pl. 13, figs 28, 29, Lejopyge laevigata perrugata Westergaard, p. 89, pl. 14, figs 1, Lejopyge laevigata armata (Linnarsson); Opik, p. 87, pl. 22, figs la Lejopyge laevigata armata (Linnarsson); Daily & Jago, pl. 62, figs 11-14,?17,? Lejopyge laevigata perrugata Westergaard; Daily & Jago, pl. 63, figs Lejopyge laevigata arrnata (Linnarsson); Jago, p. 13, pl. 2, figs Lejopyge laevigata armata (Linnarsson); Yang, p. 23, pl. 1, figs 19, Lejopyge armata (Linnarsson); Opik, p. 161, pl. 64, figs 5, Lejopyge armata (Linnarsson); Ergaliev, p. 77, pl. 2, figs 11, Lejopyge armata (Linnarsson); Yang, p. 301, pl. 1, fig Lejopyge armata trigonospinosa Yang, p. 301, pl. 1, figs 10, Lejopyge laevigata armata (Linnarsson); Liu, p. 292, pl. 209, fig Lejopyge arrnata (Linnarsson); Robison, p. 39, fig. 22. Remarks. Robison (1984, p. 44) differentiated L. armata from L. laevigata by the presence and absence of spines, particularly of pygidial marginal spines, respectively. Using this criterion, forms such as those illustrated by Daily and Jago (1975, pl. 62, figs 10, 15, 16, 18) and by Westergaard (1946, pl. 13, figs 25, 30, 31) which have very small pygidial marginal spines, were assigned to L. armata by Robison (1984). Of the specimens illustrated by Westergaard as L. laevigata armata, four specimens are pygidia and of these, two have minute marginal pygidial spines whilst the others have moderately long spines. The latter two specimens also have a constriction of the acrolobe adjacent to the marginal spines whereas the former do not. This constriction can also be clearly seen in the pygidia of L. armata illustrated by Robison (1984, fig. 22-4), Daily & Jago (1975, pl. 62, figs 12, 13), Opik (1961, pl. 22, figs 2a-4), Ergaliev (1980, pl. 2, fig. 11), Yang (1978, pl. 1, fig. 20; 1982, pl. 1, figs 9, 10, 11), Liu (1982, pl. 209, fig. 7) and to a lesser extent in specimens illustrated by Jago (1976, pl. 2, figs 5, 6, 8) and Opik (1979, pl. 64, fig. 6). Thus I suggest that the presence of relatively large pygidial marginal spines with a concomitant acrolobe constriction should be considered a diagnostic property of L. armata and that forms with minute pygidial marginal spines and unconstricted acrolobes probably belong to L. laevigata. Lejopyge laevigata (Dalman 1828) (Fig. 8) 1936 Lejopyge exilis Whitehouse, p. 96, pl. 9, fig. 9 only Lejopyge laevigata (Dalman); Westergaard, p. 87, pl. 13, figs Lejopyge laevigata armata (Linnarsson); Westergaard, pl. 13, figs 30, Lejopyge cos Opik, p. 93, pl.57, figs 5, Lejopyge laevigata (Dalman); Daily & Jago, pl. 62, figs Lejopyge laevigata armata (Linnarsson); Daily & Jago, pl. 62, figs 15, 16.? 1975 Lejopyge laevigata rugifera Westergaard; Daily & Jago, pl. 63, fig Lejopyge cos Opik; Daily & Jago, pl. 62, figs 17, 18. Diagnosis. Cephalon with axial furrows effaced distally, basal lobes clearly defined, without cephalic spines, usually nonscrobiculate. Thorax nonspinose. Pygidium with axial furrows effaced distally, with unconstricted acrolobe, occasionally with very small marginal spines. Remarks. Daily & Jago (1975, p. 530, p. 547) placed L. cos Opik 1967 in synonymy with L. laevigata arrnata (Linnarsson). This assignment was based on the presence of marginal spines on the holotype pygidium of L. cos (re-illustrated herein as fig. 8) rather than their size and relationship to the acrolobe. Taking these features into account leads me to believe that L. cos is a synonym of L. laevigata rather than L. armata (see also remarks on L. armata and L. calva.)

15 ALCHERINGA AUSTRALIAN AGNOSTIDS 189 Fig. 8. Lejopyge laevigata (Dalman), pygidium, x 8, natural mould, stereopair, illustrated as the holotype of Lejopyge cos 0pik (1967, pl. 57, fig. 5), from G131, CPC5843. Lejopyge calva Robinson Lejopyge exilis Whitehouse, p. 96, pl. 9, fig. 12 only Lejopyge calva Robison, p. 521, pl. 83, figs I Lejopyge calva Robison; Palmer, p. 27, pl. 6, figs Lejopyge sp., Daily & Jago, pl. 63, figs Lejopyge calva Robison; Daily & Jago, pl. 63, fig Lejopyge exilis Whitehouse; Daily & Jago, pl. 63, fig Lejopygepraecox Opik, p. 159, pl. 66, figs 1-7; pl. 41, fig. 1.? 1979 Pseudophalacroma dubium (Whitehouse); Opik, pl. 67, figs 3, 4 only 1984 Lejopyge calva Robison; Robison, fig. 23.? 1985 Pseudophalacroma dubium (Whitehouse); Xiang & Zhang, pl. 14, figs (not fig..13). Diagnosis. Cephalon with axial furrows nearly completely effaced, with basal lobes poorly defined anteriorly, without cephalic spines, commonly weakly scrobiculate. Thorax unknown. Pygidium nonspinose, with axial furrows weakly impressed adjacent to anterior axial segment, effaced distally, border wide posteriorly. Remarks. The specimens assigned to L. praecox by Opik (1979) are nonspinose, almost completely effaced and have the glabellar node more anteriorly located than in most species of Lejopyge. They are very similar to L. calva Robison but differ in having a slightly wider (sag.) pygidial border. This difference is almost certainly of no taxonomic significance. The pygidium tentatively associated with the holotype of L. exilis by Whitehouse (1936, pl. 9, fig. 12), and later re-illustrated by Daily and Jago (1975, pl. 63, fig. 11), most probably belongs to L. calva as the degree of effacement and the width of the border are very similar to those of the latter. Examination of the holotype cephalon of L. exilis Whitehouse (1936, pl. 9, fig. 9) shows it to be a pygidium with effacement and border morphology commensurate with an assignment to L. laevigata. Such an assignment had previously been made by Opik (1961, p. 86), though he still believed the specimen to be a cephalon. Two of the specimens illustrated as examples of Pseudophalacroma dubium (Whitehouse) by Opik (1979, pl. 67, figs 3, 4) are tentatively assigned to L. calva because of their comparable degree of effacement and because they lack the distinct elongation of the acrolobes seen in the former. Lejopyge dubium (Whitehouse 1936) 1936 Phalacrorna (?) dubium Whitehouse, p. 95, pl. 9, figs 13,?14, Pseudophalacroma dubium (Whitehouse); Opik, p. 93, pl. 22, figs Pseudophalacroma sp. K, Opik, p. 94, pl. 22, fig Pseudophalacroma (?) sp., Jago, p. 6, pl. 1, figs Pseudophalacroma dubium (Whitehouse); Opik, p. 163, pl. 67, figs 1, 2 only Pseudophalacroma dubium (Whitehouse); Ergaliev, p. 80, pl. 2, figs 4-7. Diagnosis. Cephalon elongate with axial furrows nearly completely effaced, with basal lobes poorly defined anteriorly, without cephalic spines, nonscrobiculate. Thorax probably nonspinose. Pygidium elongate, nonspinose, with axial furrows effaced distally, weakly impressed adjacent to anterior axial segment and in some specimens, adjacent to middle axial segment. Anterior transverse furrow weakly impressed. Border wide to very wide. Remarks. This species is very similar in shape to both L. calva and L. multifora. It differs from the latter in being nonspinose and in lacking the conspicuous punctation of the exoskeleton. Unfortunately, differentiating L. dubium from the former species is not as easy. Cephala assigned to L. dubium are very elongate and tend to be more highly vaulted posteriorly, whilst the pygidia tend to be more

16 1913 JOHN R. LAURIE ALCHERINGA elongate and to have a wider border than those of L. calva. Although these appear to be dubious criteria for specific differentiation their full significance is not understood, so for the present L. calva and L. dubium are retained as separate species. Lejopyge multifora Opik Lejopyge multifora Opik, pl. 65, figs 3-4. Diagnosis. Cephalon elongate, finely punctate, nonscrobiculate with axial furrows nearly completely effaced, basal lobes poorly defined anteriorly, well developed cephalic spines. Thorax with well developed fulcral spines on posterior segment. Pygidium elongate, finely punctate, nonspinose with axial furrows effaced distally, weakly impressed adjacent to anterior axial segment. Border of moderate width. Remarks. See remarks for L. dubium. Lejopyge cosfordae Opik Lejopyge cosfordae Opik, pl. 65, figs 1-2. Remarks. This name was used by Opik (1979) for a form with weakly impressed axial furrows in both the cephalon and pygidium. It was thought by Robison (1984, p. 37) to be an early holaspid of L. praecox Opik [ = L. calva Robinson, herein]. However, specimens of L. calva of similar size show nearly complete effacement comparable with that of larger specimens. Therefore, L. cosfordae is not synonymous with L. calva but is, in my opinion, probably conspecific, or at least closely related to L. elegans Tullberg. Acknowledgements I wish to thank John Shergold (B.M.R.) for giving me the opportunity and encouragement to work on these specimens; Arthur Wilson (B.M.R.) for help with photography, and Sven Laufeld and Yngve Grahn (Swedish Geological Survey) for arranging the loan of specimens held by their institution. The author publishes with the permission of the Director, Bureau of Mineral Resources, Geology and Geophysics. REFERENCES BROGGER. W. C., Om paradoxidesskifrene ved Krekling. Nyt Magazin for Naturvedenskaberne, Oslo 24(1), DALMAN, J. W., Arseberattelse om nyare zoologiska arbeten och upptacker. Svenska Vetenskapsacademien, Arsberattelser, Stockholm, 138p. DAILY, B., & JAGO, J. B., The trilobite Lejopyge Hawle and Corda and the middle-upper Cambrian boundary. Palaeontology 18, ERGALIEV, G. KH., Trilobity Srednego i Verkhnego Kembriya Malogo Karatau. Institut Geologicheskikh Nauk, Akademiya Nauk Kazakhskoy SSR, Nauka, Alma-Ata, 221p. HAIRULLINA, T. I., Biostratigrafiya i trilobity Mayskogo Yarusa Srednego Kembriya Turkestanskogo Khrebta. Ministerstvo Geologii Uzbekskoy SSR, Fan, Tashkent. l12p. HAWLE, I., & CORDA, A. J. C., Prodrom einer Monographie der b6hmischen Trilobiten. Abhandlungen der KOniglichen BOhmischen Gesellschaft der Wissenschaften 5, HILL, D., PLAYFORD, G. & WOODS, J. T., eds, Cambrian fossils of Queensland. Queensland Palaeontographical Society, Brisbane, 32p. HOWELt, B. F., Some New Brunswick Cambrian agnostians. Bulletin of the Wagner Free Institute of Science 10(2), HOWELL, B. F., Agnostida. In Moore, R. C., ed., Treatise on Invertebrate Paleontology, Part O, Arthropoda 1, Geological Society of America and University of Kansas Press, Lawrence, JAEKEL, O., ber die Agnostiden. Zeitschrift der Deutschen Geologischen Gesellschaft 61, JAco, J. B., Late middle Cambrian agnostid trilobites from north-western Tasmania. Palaeontology 19, KOBAYASHI, T., The Cambro-Ordovician shelly faunas of South America. Journal of the Faculty of Science, Imperial University of Tokyo, Section II, 4(4), KOBAYASHI, T., On the Agnostids (Part 1). Journal of the Faculty of Science, Imperial University of Tokyo, Section II 5(5), LAURIE, J. R., Revision of some Australian Ptychagnostinae (Agnostida, Cambrian). AIcheringa 12, LINNARSSON, J. G. O., Om Vestergotlands Cambriska och Siluriska aflagringar. Kongliga Svenska Vetenskapsakademiens-Handlingar 8(2), Lru YmE~, Trilobita. In The Palaeontological Atlas of Hunan. Geological Publishing House, Beijing, Lu YANHAO, ZHANG WENTANG, ZHU ZHAOLING, QIAN YIYUAN, & XIANG LIWEN Chinese trilobites, Volume l, Science Press, Beijing, 362p. LUNDQVIST, G., HOGBOM, A. & WESTERGAARD, A. H., 193 I. Beskrivning till kartbladet Lugnaas. Sveriges Geologiska Unders6kning, Ser. Aa, 172, 46p. OPIK, A. A., The geology and palaeontology of the headwaters of the Burke River, Queensland.

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