SPHENOPHRYNE - American Museum of Natural History

More documents

Recommendations

Info

112 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY NO. 253 Fig. 70. Lateral view of left posteromedial process of the hyoid of Liophryne allisoni, BPBM 9631, with the ventromedian process projecting from its anterior end. The right (posterior) end of the posteromedial process angles toward the viewer. Scale line marked in millimeters. stenodactyla, where four of six specimens show no mineral deposits and two others show only slight amounts. Dense staining of cartilage may mask mineral deposits in my specimen of A. robusta, and the sternum is damaged in specimens of L. allisoni and O. alpestris. MYOLOGY I offer here only a few comments on myology, as this topic was not within the intended scope of the work. This is not to deny the potential importance of further myological study, the value of which in microhylid systematics has been amply demonstrated (e.g., Burton, 1984, 1986). JAW MUSCULATURE: Burton (1986) noted that in almost all genyophrynines the M. depressor mandibulae arises largely from the dorsal fascia, as illustrated for ‘‘Sphenophryne schlaginhaufeni’’ (probably L. rubra) by Burton (1986: fig. 11D). L. rhododactyla and O. stenodactyla (fig. 74) also have this common condition. The exceptions, assigned to the genus Albericus, have the origin of this muscle largely restricted to the otic ramus of the squamosal and the prootic region (Burton and Zweifel, 1995, fig. 3). SUPERFICIAL MANDIBULAR MUSCULATURE: The Asterophryinae exhibit variation in the number and placement of supplementary slips of the M. interhyoidius, whereas the Genyophryninae show only a single slip, presumably a primitive condition (Burton, 1986). Burton (1984) called attention to differences in the supplementary slip that distinguish Sphenophryne (in the earlier, broad sense) from Cophixalus: ‘‘Supplementary slip . . . narrow, arising from either a posterior tendon or from dentary, and oriented parallel to the mandible’’ (Cophixalus), or ‘‘broad, arising from ventral fascia of angulosplenial, and oriented medially and only slightly anteriorly’’ (Sphenophryne). Zweifel (1985b) confirmed these observations for additional Australian species of the two genera. Typical conformation of the supplementary slip for two Australian Austrochaperina is illustrated for A. fryi (as Sphenophryne, sp. nov.) in Burton (1984: fig. 1B) and A. robusta (as S. robusta) in Zweifel (1985b: fig. 55B). Six New Guinean species, A. palmipes, Liophryne dentata, L. rhododactyla, L. schlaginhaufeni (fig. 75C), Oxydactyla crassa, and O. stenodactyla (fig. 75A), resemble these closely, but Sphenophryne cornuta (fig. 75B) differs in that the muscle bundle is abruptly tapered posteriorly and has its fiber orientation more nearly parallel to that of the mandible. While awaiting confirmation of the situation in additional species, a tentative conclusion is that the condition in cornuta is derived relative to that common to other species. KARYOLOGY Information is available for just nine species of Austrochaperina and Liophryne, four of them Australian endemics (Kuramoto and Allison, 1989; Mahony et al., 1992; James Menzies (personal commun.). Sphenophryne and Oxydactyla have not been karyotyped. Seven species have the presumably primitive diploid number 2N 26 (see discussion in the papers cited above and in Bogart and Nelson, 1976) consisting of five large and
2000 ZWEIFEL: PARTITION OF SPHENOPHRYNE 113 Fig. 71. Terminal phalanges of third fingers of Austrochaperina, Liophryne, Oxydactyla and Sphenophryne; scale lines marked in 0.1-mm intervals. A. O. stenodactyla, AMNH A92801. B. O. alpestris, AMNH A65299. C. O. brevicrus, AMNH A43761. D. O. coggeri, AMNH A140874. E. A. brevipes, AMNH A130527. F. L. allisoni, BPBM 9631. G. L. rhododactyla, BPBM 9793. H. L. dentata, UPNG 2641. I. L. schlaginhaufeni, AMNH A78183. J. A. gracilipes, AMNH A90407. K. A. novaebritanniae, AMNH A88569. L. A. blumi, UPNG 9559. M. S. cornuta, AMNH A92804. N. A. basipalmata, AMNH A129495. O. A. rivularis, AMNH A88445. P. A. palmipes, AMNH A92807. Q. A. derongo, AMNH A145507. eight small chromosome pairs: Austrochaperina adelphi, A. fryi, A. gracilipes (J. Menzies, personal commun.), A. pluvialis, A. palmipes, A. robusta, and Liophryne rhododactyla. One Papuan species, Liophryne schlaginhaufeni, has 2N 30, and another, ‘‘sp. B’’ of Mahony et al., probably A. derongo, 14 14 I have not examined the two specimens cited, AMS R130754 and R116927 (the latter reported as ‘‘R116297,’’ which is a snake, whereas 116927 is an Austrochaperina from the locality given), but they were collected along with a series of A. derongo, and the only other species of Austrochaperina in that collection was the distinctive A. palmipes, which has 2N 26. has 2N 24. Mahony et al. (1992) demonstrated that the karyotype of schlaginhaufeni could be derived from a 2N 26 karyotype by fission, although the recovered karyotype does not precisely match any of those available for comparison. These authors were ‘‘unable to suggest a simple mechanism for the diploid number reduction’’ to 2N 24 in ‘‘sp. B.’’ The fact of variation in diploid numbers in this small sample gives hope that data from additional species may be of use in estimating relationships, but for the present we have little more than isolated facts.
Page 1 and 2:
PARTITION OF THE AUSTRALOPAPUAN MIC
Page 3 and 4:
2000 ZWEIFEL: PARTITION OF SPHENOPH
Page 5 and 6:
Page 7 and 8:
Page 9 and 10:
Page 11 and 12:
Page 13 and 14:
Page 15 and 16:
Page 17 and 18:
Page 19 and 20:
Page 21 and 22:
Page 23 and 24:
Page 25 and 26:
Page 27 and 28:
Page 29 and 30:
Page 31 and 32:
Page 33 and 34:
Page 35 and 36:
Page 37 and 38:
Page 39 and 40:
Page 41 and 42:
Page 43 and 44:
Page 45 and 46:
Page 47 and 48:
Page 49 and 50:
Page 51 and 52:
Page 53 and 54:
Page 55 and 56:
Page 57 and 58:
Page 59 and 60:
Page 61 and 62: 2000 ZWEIFEL: PARTITION OF SPHENOPH
Page 111: 2000 ZWEIFEL: PARTITION OF SPHENOPH
show all

SPHENOPHRYNE - American Museum of Natural History

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?