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Arquivos de Zoologia

peribuccal muscles. Jaws (figs 81,416) two very laige plates, somewhat thick; anterior cut edge smooth and dark brown; other regions pale brown. Inner surface of dorsal wali of buccal mass with 2 broad longitudinał folds as ventral limit of a dorsal chamber; dorsal inner surface of this dorsal chamber with several narrow longitudinał folds (figs 413-416: o2). Pair of narrow furrows in late-ral region, longitudinał, fmishes posteriorly in each esophageal pouch. Esophageal pouch a pair of semi-spherical, hollow structures, well delimited between buccal mass and esophagus limit, lateral situated (fig. 415). Odontophore (figs 417-421) si-milar to those of preceding species; distinctive features are: 1) ml,jugal muscles very developed, mainly near median linę in dorsal and ventral regions, connecting strongly odontophore and buccal mass in adjacent inner wali of snout; 2) m2 absent; 3) broad insertion of jaws and peribuccal muscles (ji); 4) very short radula (less than 30 rows of teeth); 5) m6, horizontal muscle very thick (fig. 419); 6) a pair of probable m8 in inner region of odontophore; 7) mil not connected with cartilages, inserted in radular nucleus; 8) ml3, a strong muscle originated in ventral peribuccal region, inserted in radular nucleus. Radula (fig. 111) see Houbrick (1981a: 274, fig. 6; 1989: 2, figs. 1-2) description. Esophagus single, without visible glands; folds of dorsal chamber of buccal mass gradually faint in anterior half of esophagus inner surface; posterior esophagus with a single longitudinał fold developed. Salivary glands broad in anterior and posterior regions of nerve ring, passing through it; gradually narrow until middle region of esophagus. Salivary glands aperture in dorsal posterior region of buccal mass. Stornach and posterior digestive gland not seen, but well described by Houbrick (198la: 275-276, fig. 5b; 1989: 3, figs. 3-5); style sac rudimentary, central pad-like structure, two openings to digestive gland. Intestine sinuous within anterior digestive gland. Rectum somewhat broad, with fecal pellets almost spherical, not compacted obliquely; anus siphoned, very posterior from mantle border. Other details of digestive system in Houbrick (198la: 274-276, figs 4-5; 1989: 3).

Genital system. Małe and female organs not seen completely, they are well described by Houbrick (1981 a: 277-278, fig.4). Notę the probable protandry, seminal receptacle within pericardium, and a thick opened pallial oviduct without chambers.

Nervous system (figs 411, 413). Pair of buccal ganglion smali, anterior to esophageal pouches. Other details in Houbrick (198la: 276-277, fig. 5a).

Measurements (in mm). USNM 867174: 55.0 by 20.0; USNM 691560: 78.2 by 28.0.

Distribution. SW Australia coast.

Habitat. See Houbrick (1981a: 279).

Materiał examined. Australia; Western Australia; Cape Naturaliste, Bunker Bay, 7 specimens, USNM 691560 (Rosewater & Wilson col. 13/viii/l 966); Denmark, Wilson Inlet, Ocean Beach, 1 specimen, USNM 867174 (27/i/l 988, Houbrick, R.S. col.).

Remarks. C. symbolicum was included in the genus Cerithium in early papers (see Houbrick, 198 la: 280-282 for a fuli historie) among others, and finally transferred to fossil genus Campanile by Iredale (1917), becoming the single survivor of a large, diverse, complex taxon, that attaincd its apogee during the early Tertiary. Specimens of Campanilidae generally had large size, sometimes greater than a meter in length (Jung, 1987; Houbrick, 1989).

The anatomy of C. symbolicum was extensely studied by Houbrick (198la) and the aberrant characters of this species let some doubts on its systematic placement. Based on new studies including aspects of Campanile (Haszprunar, 1985, 1988; Salwini-Plawen & Haszprunar, 1987; Healy, 1983; 1986a, b), Houbrick madę a reevaluation of his previous paper in 1989, raising to it a superfamilial rank: Campaniloidea.

In present study the above cited controversy was considered, C. symbolicum was included in phylogenetic analysis with hope if it belongs to another, i.e., non-cerithioidean group, this would appear. Comments on each character are found in Discussion. Although having a large size for a cerithioidean, C. symbolicum probably evolved from giant forms, being result of a miniaturization process. If so, several adaptations to laige size, as bipectinate osphradium, large jaws, complex stornach, etc., are still present and may be regarded as autapomorphies. The Campanile diaphragm-like septum of haemocoel is similar to those that occur in Strombidae (person, obs.), and appears to be other adaptation to large size.