Early Lineages of Gonyleptidae (Arachnida Opiliones Laniatores)
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Tropical Zoology 7: 343-353, 1994 Early lineages of Gonyleptidae (Arachnida Opiliones Laniatores) ADRIANo B. KuRY Escola de Ciencias Biol6gicas, Universidade do Rio de Janeiro, Rua Frei Caneca 94, Rio de Janeiro 20.211-040, RJ, Brazil Received 8 June 1993, accepted 18 December 1993 As result of cladistic methodology applied to the study of Gonyleptidae, four precocious branches are newly recognized in the phylogeny of the family. Three new subfamilies are proposed and diagnosed and a new concept is given for the Bout guyiinae Mello-Leitao 1923. Metasarcinae, a new subfamily is proposed for the Bolivian Metasarcus Roewer 1913 (formerly in Mitobatinae) and an undescribed Argentinean genus. Chaconatus Roewer 1929 (formerly in Prostygninae) is herein considered to be a new junior subjective synonym of Metasarcus. Heteropachylinae, a new subfamily is proposed for nine genera formerly described as Gonyleptinae or Pachylinae, and distributed along the Brazilian coast. Cobaniinae, a new subfamily is proposed for the genus Cobania Roewer 1913. Bourguyiinae should be the correct spelling of a subfamily name based on the generic name Bourguyia Mello-Leitao 1923. In the present new concept, four of its five genera are removed, while eight others are transferred from the Gonyleptinae, Pachylinae and Progonyleptoidellinae. To recon struct the phylogeny of Gonyleptic,lae, 16 morphological characters were analysed through HENNIG 86, providing a single most parsimonious cladogram of CI = 0. 77. The branching pattern obtained is: (Metasarcinae (Heteropachylinae (Cobaniinae (Bourguyiinae + the other Gonyleptidae))). Piresa angulispinosis H . Soares 1966 is newly referred to Mangaratiba Mello-Leitao 1940. KEY WORDS: Arachnida, Gonyleptidae, new subfamilies, cladistics, Neotropics. Introduction 344 Phylogeny 344 Systematic accounts 349 Metasarcinae n. subfam. 349 Heteropachylinae n. subfam. 350 Cobaniinae n. subfam. 351 Bourguyiinae Mello-Leitao 1923 351 Conclusions 35~ Acknowledgements 352 References 352 344 A.B. Kury INTRODUCTION The increasing knowledge of male genitalia in the Gonyleptidae, interpreted in the light of cladistic methodology, will surely lead to major changes in the concept of this family. As a first step, the Cranainae and related subfamilies were considered not to form a monophyletic group with the rest of the Gonyleptidae, which have the Cosmetidae as a sister group (KURY 1992). The comparative study of genital morphology (mainly of Brazilian genera), usually available from modern descriptions, brings new strength to corroborate this view. The present discovery of <diving-fossils» reveals animals with a Cosmetidae-like genitalia incarnated in a definitively Gonyleptidae body. Features present in the penis of (1) Heteropachylus Roewer 1913 and allies (from the Brazilian Atlantic coast), (2) Metasarcus Roewer 1913 from Bolivian Chaco and an undescribed genus from Argen tina (E. MAURY pers. comm.), (3) Cobania Roewer 1913 and (4) the Bourguyiinae, should all be thought to be remnants of the condition present in the groundplan of Cosmetidae + Gonyleptidae. These features are modified in the other Gonyleptidae, and the primitive state conserved only in these four minor groups. According to the present hypothesis of phylogeny, three new subfamilies of Gonyleptidae are proposed, and the concept of Bourguyiinae considerably altered. PHYLOGENY Based on previous study of the phylogeny of Gonyleptidae and related families (KURY 1992), Gonyleptidae and Cosmetidae are here assumed to be sister groups. The monophyly of the Cosmetidae is clearly supported by many autapomorphies in relation to the groundplan Cosmetidae/Gonyleptidae. The typical cosmetid penis possesses a well defined rectangular ventr.al plate, with a-short and thick stylus bearing a spiny mat and a thumb-like dorsal process arising from the glans (a similar structure is found in the Stygnidae). The typical gonyleptid penis shows also a well defined ventral plate, either rectangular or piriform, the glans bears a slender sigmoid stylus and a fan-like ventral process; a dorsal process is absent. The four groups of «living-fossils» cited above show intermediate features on penial morphology. Sixteen morphological characters, listed in Table 1, were cladisti cally analysed to construct a most parsimonious hypothesis of relationship among the major groups of Gonyleptidae. The matrix has been analysed through H ENNIG 86 (FARRIS 1988), with Cosmeti dae as an immediate outgroup. Trees were rooted by a hypothetic;al ancestor plesio morphic for all character states (Table 2). The multistate character 1 was considered as unordered, because there was no obvious degree of similarity justifying any particular sequence of transformation. The exact algorithm used here - «implicit enumeration» - yielded a single completely resolved most parsimonious tree (Fig. 6) with length 22, CI (consistency index) = 0. 77 and RI (retention index) = 0. 73. The following hypotheses of character transformation (see characters mapped on cladogram of Fig. 6) better explain the data: the clade Cosmetidae/Gonyleptidae acquired as groundplan synapomorphies the saddle-shaped eye mound (char. 1, Fig. 2b) and spiny mat on stylus (char. 2, Fig. 5b). As an alternative optimization, the Early gonyleptid lineages 345 Table 1. Morphological characters used to reconstruct the phylogeny of Gonyleptidae. Zero is the plesiomorphic state, 1 is the apomorphic condition for a binary character, a-b are diferent apomorphic states of a multistate character. 1. Eye mound: (O) convex, without depression, (a) saddle-shaped, (b) flattened, with hemispherical median tubercle. 2. Stylus: (0) ventrally smooth, (1) with mat of spines. 3. Chelicerae of male: (0) much swollen, (1) as that of female. 4. Femur IV of male: (O) without dorso-basal apophysis, (1) with pointed dorso-hasal apophysis. 5. Lateral margin of scute: (0) without special features, (1) bordered by a crest of blunt tubercles. 6. Apophysis of male coxa IV: (0) single branched, (1) bifurcated. 7. Ventral process of glans penis: (0) absent, (1) present. 8. Dorsal process of glans penis: (0) present, (1) absent. 9. Free tergite III: (0) without remarkable armature, (1) with conic projection, immense in male, smaller in female. 10. Pedipalpal femur: (0) without ventral armature, (1) with ventral row of stout spines. 11. Pedipalpal patella: (0) unarmed, (1) with a stout mesal spine. 12. Femur IV of male: (0) short and armed with rows of spines, (1) elongate and weakly armed. 13 . Free tergites: (0) independent of scute and with rounded corners, (1) with projected corners and more or less fused with scute. 14. Area III of dorsal scute: (0) with two paramedian spines, (1) unarmed. 15 . Tegument: (0) coriaceous, yellow to brown, (1) glossy black. 16. Microsculpture of dorsal scute: (O) finely granular, (1) densely · grouped round tubercles. Fig. 1. - Bourguyia a/biornata Mello-Leitao 1923 (Museu de Zoologia da Universidade de Sao Paulo 10.580): distal part of penis, dorso-lateral view. This structure marks the transition between the typical cosmetid glans to the typical gonyleptid one; d = dorsal process, s = stylus, v = ventral process. 346 A.B. Kury Table 2. Matrix of distribution of character states for six terminal taxa of Gonyleptidae and the outgroup. 1 1 1234567890123456 Ancestor 0000000000000000 Cosmetidae a100000000000000 Metasarcus a-----0-----11110000 Undescribed genus a111000011110000 Heteropachylinae 0111100000001100 Cobania 0011100000000111 Bourguyiinae b010111000010100 Other Gonyleptidae 0011111100000000 .~... b a ~- 1!.. ............. ..... ~ .. c Fig. 2. - Transformation series of the eye mound in Gonyleptidae: (a) is the condition present in the primitive Tricommatidae and cranaine-like groups; (b) occurs in the ground plan of the Cosmetidae and in the Metasarcinae (and convergently in the Agoristenidae and in highly derivative Gonyleptidae as the Caelopyginae); (c) is exclusive of the Bourguyiinae. a b e Fig. 3. - Transformation series of opistosomatic characters. Abdominal scute: (a) area III armed, lateral margins without special tuberculation as in Cosmetidae and Metasarcinae; (b) area III unarmed, lateral margin bordered by a crest of rounded tubercles as in most Gonyleptidae. Free tergites: (c) as in the Cosmetidae, Stygnidae and many Gonyleptidae; (d) as in the Metasarcinae; (e) as in the Heteropachylinae. Early gonyleptid lineages 347 f e g Fig. 4. -Transformation series of appendicular characters. Chelicerae: (a) swollen as in the groudplan of Stygnidae, Cosmetidae and cranaine-like groups; (b) as in the Gonyleptidae. Pedipalps: (c) femur and patella poorly armed as in most Gonyleptidae; (d) femur with a row of ventral spines and patella with stout mesal spine as in the Metasarcinae. Leg IV of male: (e) simple coxal apophysis as in the Cosmetidae, Metasarcinae, Heteropachylinae and Cobaniinae; (f-g) bifid apophysis as in the Bourguyiinae (/) and the other Gonyleptidae (g) ; (h) femur without dorso-basal apophysis as in the Cosmetidae and Metasarcinae; (i) femur with apophysis as in most Gonyleptidae; (j) femur short and curved as in the groundplan of Cosmetidae, the Heteropachylinae, Cobaniinae; (k) elongate femur as in the Metasarcinae and Bour guyiinae. 'f?fd- f(e Fig. 5. - Transformation series of genital characters. (a) Stylus smooth as in the Stygnidae, cranaine-like groups and most Gonyleptidae; (b) stylus with a spiny mat as in the Cosmetidae and early derivative Gonyleptidae; (c) glans only with thumb-like dorsal process, as in