Daulestes kulbeckensis Trofimov and Nessov, 1979

Archibald, J. David & Averianov, Alexander O., 2006, Late Cretaceous asioryctitherian eutherian mammals from Uzbekistan and phylogenetic analysis of Asioryctitheria, Acta Palaeontologica Polonica 51 (2), pp. 351-376 : 353-357

Daulestes kulbeckensis Trofimov and Nessov, 1979 in Nessov and Trofimov 1979

Figs. 1 , 2, Tables 1, 2.

1979 Daulestes kulbeckensis sp. nov.; Nessov and Trofimov 1979: 953,

fig. 1. 1981 Daulestes kulbeckensis ; Nessov 1981: pl. 10: 18. 1982 Daulestes kulbeckensis ; Nessov 1982: pl. 1: 6. 1985 Kumlestes olzha sp. nov.; Nessov 1985: 9, pl. 2: 1. 1991 Daulestes kulbeckensis ; Nessov and Kielan−Jaworowska 1991:

fig. 1. 1991 Kumlestes olzha ; Nessov and Kielan−Jaworowska 1991: fig. 1. 1994 Daulestes kulbeckensis ; Nessov et al. 1994: 55, pl. 1: 2. 1994 Kumlestes olzha ; Nessov et al. 1994: 60, pl. 2: 2. 1997 Daulestes kulbeckensis ; Nessov 1997: pl. 46: 6. 1997 Kumlestes olzha ; Nessov 1997: pl. 45: 7. 2000 Daulestes kulbeckensis ; Averianov 2000: fig. 30.4A, B. 2000 Kumlestes olzha ; Averianov 2000: fig. 30.5A, B. Holotype: CCMGE 1/11758, right dentary with partial alveolus for posterior root of two rooted canine, two alveoli for p1, partial anterior and posterior roots for p2, p4 lacking protoconid apex, p5 lacking protoconid apex, m1 lacking para− and metaconid apices,anterior alveolus for

m2 (see Discussion for the interpretation of the anterior dentition). CBI−4b); URBAC 99−25 , right dentary with alveoli for Found 1978. m1–3, m3 was erupting (CBI−14). Type locality and horizon: CDZH−17a, Dzharakuduk, Kyzylkum Desert, Revised diagnosis.—Intermediate in size between Uckudu−

Uzbekistan. Bissekty Formation, Upper Cretaceous (Turonian). kodon gen. nov. and D. inobservabilis , averaging 7.5% (range

Referred specimens.— URBAC 98−126 , probably associated of 3–16%) larger based on measurements of m1 and m2 and lingual and labial parts of a left M1 (CBI−14) ; URBAC averaging 23.5% (range of 19–28%) larger than the former 98−127, an unworn right M2 lacking the metacone (CBI−14); species based on measurements of M1 and M2, and averaging URBAC 03−85 , right dentary with m1–2, m3 trigonid 5.7% (range of 12% larger – 23% smaller) smaller based on partially erupted, and alveoli for p5 (CBI−14) ; CCMGE measurements of m1 and m2 and averaging 4.5% (range of 1/12176, left dentary with damaged m1–2 and alveoli for 0–8%) smaller based on measurements of M1 and M2 than the erupting m3 (the holotype of Kumlestes olzha Nessov, 1985 , latter species.

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Description.—Here we describe only newly collected material of D. kulbeckensis . Description of the holotype dentary can be found in Nessov et al. (1994).

Only two isolated upper molars are attributable to D. kulbeckensis : URBAC 98−126 (M1) and 98−127 (M2). M1 consists of two parts, probably belonging to the same specimen ( Fig. 1A ). The ectoflexus is not deep and the stylar shelf is about twice wider labial to the metacone than labial to the paracone. The parastylar lobe is large and anteriorly protruding, with a large parastyle. A distinct small preparastyle was apparently present but has mostly worn away. The stylocone is distinct but is much smaller than the parastyle. There are no distinct stylar cusps posterior to the stylocone. The metastylar lobe is close in size to the parastylar lobe, extending a greater distance labially, but the metastylar lobe does not extend posteriorly. Preparacrista and postmetacrista are ridge−like and relatively high; both crests are heavily worn. The metacone is smaller and shorter than the paracone; the bases of the cusps are merged. The conules are sharp, large, and winged; the paraconule being closer to the protocone than is the metaconule. The sharp internal postparaconule and premetaconule cristae divide the trigon basin into concave conular basins and a deeper, concave primary trigon basin. The protocone is about the height of the metacone, but lower than the paracone, and is relatively unexpanded anteroposteriorly. There are no lingual cingula.

M2 ( Fig. 1B ) differs from M 1 in having a parastylar lobe that extends farther anterolabially than more anteriorly as in M1, which results in a deeper ectoflexus. The preparacrista is directed towards the parastyle rather than contacting the stylocone. The preparaconule crista and paraconule bulge anteriorly from the anterior margin of the crown.

The three referred dentaries of D. kulbeckensis all had an m3 that was not fully erupted (hidden in crypt in URBAC 03−85) ( Fig. 2B). In CCMGE 1/12176 and URBAC 99−25 the dentary is swollen surrounding the alveoli for m3, which are close to the anterior slope of the coronoid process. In URBAC 03−85 there are several very small masseteric foramina. In URBAC 99−25 on the medial side of the coronoid process there is a subhorizontal line delimiting the ventral border for the temporalis muscle. This specimen also preserves the base of the mandibular angle and a large oval−shaped and posteriorly directed mandibular foramen dorsal to the angle.

The p4–5 protoconids are mostly missing in the type specimen ( CCMGE 1 /11758), but enough is preserved to show that p4 is distinctly longer than p5, and that the singled−cusped talonid extends the full width of the crown ( Fig. 2A) .

The m1–2 ( Fig. 2) are very similar in structure, differing slightly in that the m1 has a more open trigonid angle and a smaller and more labially displaced paraconid. The m2 is slightly longer as the result of a slightly more elongate talonid. On unworn m1s and m2s, the trigonid is about twice the height of the talonid. The protoconid is considerably higher and larger than the metaconid. The paraconid is smaller and shorter than the metaconid. There is a distinct, flat−bottomed, triangular trigonid basin, which is open lingually between the paraconid and metaconid bases. The precingulid is short, narrow, and terminates at the paracristid notch. The talonid is narrower than the trigonid. The hypoflexid is deep. The cristid obliqua terminates at the protocristid notch on m1 and somewhat lingual to this notch on m2. The talonid basin is deep, especially in its anterolingual corner, where it receives the protocone during centric occlusion. The hypoconid is the largest and tallest of the talonid cusps and the entoconid is the smallest. The hypoconulid is equidistant from the other talonid cusps and is posteriorly projecting.

Measurements —See Tables 1 and 2.

Figures

Fig. 1. Stereopairs of Daulestes kulbeckensis Trofimov and Nessov, 1979; Dzharakuduk, Uzbekistan, Late Cretaceous (Turonian). A. URBAC 98−126, probably associated lingual and labial parts of a left M1 in, occlusal (A1), labial (A2), and anterior (A3) views. B. URBAC 98−127, a right M2 lacking the metacone, in occlusal (B1), labial (B2), and anterior (B3) views.