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200

Arquivos de Zoologia

but the same reasoning as for character 113 can be applied here. Aphaly is the condition of the archaeogastropods, but also occurs in some Ctenoglossa (among Caenogastropoda) and in Allogastropoda. Based on parsimony and comparisons with the archaeogastropods, the aphalate condition is also regarded as plesiomorphic. This agrees with Haszprunar (1988) and Ponder & Lindberg (1997).

121. Parthenogenesis. 0= absent; 1= present (thiarids) (CI= 100, RI= 100).

The supposed parthenogenesis is based on the lack of males and on the data of the literaturę.

Ecology

122. Environment: 0= marinę; 1= freshwater (thiarids and pleurocerids) (CI= 50, Ri= 85).

Cladistic Analysis Discussion of cladograin

Comparing the tree obtained in the present study with that shown by Houbrick (1988, fig. 2) for the phylogeny of Cerithioidea at the family Ievel, it is elear that they have little in common. This is probable largely due to the outgroup choice. Houbrick chose Hydrobiidae and Strombidae (Caenogastropoda), while mainly the archaeogastropods were chosen herein (see explanation above). This choice resulted in the inversion of polarization of several important characters. The data of the Houbrick (1988: 102-105) were reanalyzed using the archaeogastropods as outgroup, the inversion of the polarization of the following characters was detected: 1,2, 7,8,9, 10, 11, 14, 19, 20, 26, 28, 33, 35, 37, 40, 42, 43, 49, 50 and 51. The table was copicd without any modification, although, some few modifications would be possible to be done with the results of other species analyzed here. The obtained tree (Fig. 442) is the consensus of 4 equal-parsimonious tTees. TheTurritellidae-Vermetidae inverted their position to the base, with Campanilidae as second branch. This new tree is morę or less compatible with the obtained in this study. However, the position of the Modulidae and Batillariidae is quite different (may be the result of the insertion of the study of the other structures such as buccal mass muscles). The cerithioidean synapomorphies of this new tree based on Houbrick data are the following: character #1 (elongate shell), #15 (eiliated groove on right of foot), #43 (sub-esophageal ganglion close from pleural ganglion), #47-48 (sperm dctails), #53 (se-minal receptacle) and #54 (bursa copulatrix).

Comments on nodes

From the nodes, only some with interesting, polemic or dubious data are chosen for some comments.

Node 1. In this study, 23 cerithioidean synapomorphies were detected, these are important for the comprehension and establishment of the superfamily among the Caenogastropoda. Up to present, this taxon was only united by shared plesiomorphies. The great difficult is, however, that most synapomorphies were not maintained in all its representatives, but so modified or even lost at least in one, and sometimes in several groups. However, the odontophoric muscle m 11 free from the m4 (character 75) and the muscle m 12 (79) are maintained in all examined species, inclusive Campanile. From the synapomorphies, those regarded as morę important are: papillate mantle border (23), aortas attached directly in stornach (separated only by pericardium membranę) (56), the migration of mil to median region and detachment from m4 (75), the m8 (72), the ml2 (79), the gastric central pad (93) and the ovopositor (114). With a list of cerithioidean synapomorphies known, it is possible do reevaluate some incertae sedis taxa with probable close affinity with cerithioideans. Some examples are Abyssochrysidae Houbrick, 1979; Plesiotrochidae Houbrick, 1990b and Provannidae Waren & Ponder, 1991.

Modulus modulus. From those analyzed cerithioideans, M. modulus is that which brings the larger quantity of plesiomorphies, including the turbinoid shell shape. However, this species presents an interesting group of highly modified characters, such as morę distal position of eyes in tentacles (18), anterior extremity of osphradium with a strong zigzag (31) and the total separation of style sac from intestine (98).

Node 2. This branch reunites all other