Antechinus mysticus

Baker, Andrew M, Mutton, Thomas Y & Dyck, Steve Van, 2012, A new dasyurid marsupial from eastern Queensland, Australia: the Buff-footed Antechinus, Antechinus mysticus sp. nov. (Marsupialia: Dasyuridae), Zootaxa 3515, pp. 1-37 : 31-32

Description of A. mysticus holotype JM19707

Pelage: Fur over the whole body is bicoloured with the base approx ¾ of each hair being dark mouse grey and the apical ¼ being the colours described as follows. The fur on the head is greyish olive to deep greyish olive in colour with a mildly grizzled appearance. The fur colour on the back changes gradually from greyish olive on the head to buffy olive / Isabella color towards the rump. The flanks to underside area between the hands and feet are honey yellow. The belly is fur is chamois. The fur on the upper hands and feet is olive-buff to deep olive buff with some scattered hairs buffy brown. The fur on the upper and lower base of the tail is mostly deep olive, with some darktipped hairs, changing gradually to mostly fuscous black towards the tip, such that the tail appears to subtly darken along the length. The hairs at the base of the tail are about 3mm long, gradually lengthening to 4–5 mm towards the tip. Guard hairs are 10–15 mm long on the rump and reduce to 4mm on the crown of the head; guard hairs vary in colour from almost entirely fuscous black, to the basal half fuscous black and an almost colourless apical half. Fur of the mid-back is about 9mm long but varies in colour, from the basal band being 6mm long and mouse grey, the medial band buff olive and 2 mm long, and the apical band 1mm long and fuscous black, to other hairs with the basal band being 6mm long and mouse grey and the apical band 3mm long and buffy / Isabella color. There are patches of distinctly lighter fur above and below the eye but it does not form a complete ring, reduced to a strip of lighter olive-buff fur above and below, surrounded by greyish or dark tipped fur. The ventral fur is 5–6 mm long with 7–8 mm long guard hairs.

Vibrissae: there are approximately 19 mystacial vibrissae on each side, the more dorsal fuscous black, ranging to the more ventral almost colourless. Supraorbitals (fuscous black) number 2 and 2; ulna-carpals (colourless) number 3 and 3; genals (fuscous black and colourless) number 4 and 4; submentals (colourless) number 2.

Hindfoot: the interdigital pads are separate, enlarged, elongate and striate. The striate hallucal pad is fused to the elongate, striate post-hallucal pad on each foot, with the appearance of a single enlarged, sinuous pad. The metatarsal pad is enlarged, elongate and striate. Terminal pads of digits are weakly striate on toes 2–5 and more strongly striate on toe 1. Hair on the foot covers the heel and extends diagonally partially across the foot. Granules of varying size (0.2–0.7mm) cover the undersurface of the foot.

Ears: the ears are large with a simple, uncurled supratragus.

Tail: the tail is thin and tapers towards the tip, and is about 8mm shorter than head-body length.

External Measurements: wt 46.00g; head-body length 112.90mm; tail-vent length 104.80mm; hindfoot length 18.30mm; ear length 18.70mm.

Dentition: Upper incisors: I1 is sturdy, procumbent and high-crowned. It is curved and separated from I2 by a diastema. Left and right I1 are almost in contact. In crown height, I2 I3 and I4 are subequal. All upper incisors have buccal cingula, but only I1 has a (weak) lingual cingulum. I4 carries no anterior or posterior cusp and its root is narrow.

Upper canines: C1 is narrow and caniniform with a distinct boundary between root and crown. The buccal cingulum is stronger than the lingual. There is no anterior cusp, but a minute posterior cusp is present.

Upper premolars: A minute diastema occurs between P1 and P2 and P2 and P3. All upper premolars carry strong buccal and lingual cingula. In crown size: P3>P2>P1. Small anterior cingular cusps and posterior cusps occur on P1 and P2; P3 lacks an anterior cusp but exhibits a strong posterior cusp. P1 and P2 crowns are roughly oval in shape and carry a small post-lingual lobe and P3 carries a slightly larger medial-lingual lobe.

Upper Molars: M1: The posterior tip of P3 touches the parastylar corner of M1 anterior to, and against, the base of stylar cusp A, which is small. The anterior cingulum below stylar cusp B is short, broad and complete. Stylar cusp B is moderately well-developed. Stylar cusp C is small and broadly rounded. A minute protoconule is present at the base of the paracone apex. Stylar cusp D is large and rounded. Stylar cusp E is not visible on either the left or right M1. M1 shows a weakly developed posterior cingulum.

M2: In M2, the very broad anterior cingulum, which contacts the metastylar corner of M1, tapers abruptly as it progresses down and along the base of the paracrista and degenerates labially, about half the way to the base of the paracone apex. A small protoconule is present at the base of the paracone apex. All stylar cusps A–E are present, but E is minute and broadly rounded and B is small and rounded. Stylar cusp D is well developed and broadly peaked, and there is a poorly developed posterior cingulum that degenerates half-way toward the post-protocrista. The post-protocrista is well developed and peaked.

M3: In M3, the broad anterior cingulum, which does not quite contact the metastylar corner of M2, tapers abruptly as it progresses down and along the base of the paracrista and degenerates labially, about half the way to the base of the paracone apex. A small protoconule is present at the base of the paracone apex. All stylar cusps A–E are present, but E is minute and broadly rounded and B is small and rounded. Stylar cusp D is well-developed and peaked, about 2/3 size of cusp D in M2. The posterior cingulum is very weakly developed. The post-protocrista is well developed and broadly rounded.

M4: In M4, the metastylar corner shows no development. The broad anterior cingulum is just complete; there is no posterior cingulum. The protocone is reduced and moderately narrow. The post-protocrista is weakly developed and broadly rounded.

Skull: The dorsal surface of the rostrum is not entirely flat but exhibits some longitudinal mid-line swelling halfway along the length of the nasals. The left and right alisphenoid tympanic bullae are moderately widely separated and only moderately enlarged. The foramen pseudovale is large and not bisected by a bridge of the alisphenoid. The eustachian canal opening is moderately large. The internal jugular canal foramina are relatively large, the canals are slightly raised. The posterior lacerate foramina are much larger and exposed, and the entocarotid foramina are small. The anterior palatal vacuities extend from the posterior end of the I2 root and terminate at the level of the posterior root crown of the upper canine teeth. Posterior palatal vacuities originate at the posterior end of the M1 protocone root and terminate at the level of the M4 metacone.

Dentary: Lower incisors: I1 is greater in crown height than I2. I1 and I2 are oval in anterolateral view and gougelike in occlusal view. I2 is taller in crown height than I3. I3 is incisiform in lateral view with a small posterior cusp at the base of the crest, which descends posteriorly from the apex of the primary cusp. There is a narrow gap between the I3 posterior cusp and the lower canine.

Lower canines: C1 is caniniform, broad and characterized by erect projection and curvature from root crown to tip. It has weak buccal and strong lingual cingulation and a small posterior cusp.

Lower Premolars: The premolar row is relatively long and uncrowded, with the first two premolars narrowly separated and a larger gap between P2 and P3. P1-3 are moderately cingulated buccally and lingually. In crown height, P2 is taller than P1; P1 and P3 are subequal in crown height. Left and right P3 are double rooted and not transversely aligned in the tooth row. The crown of P3 possesses a small posterior cusp; P2 possesses a broader posterior cusp. All premolars are without anterior cusps. Both P1 and P2 are broad, with broadly rounded posterolingual lobing.

Lower Molars: M1: The M1 talonid is wider than the trigonid. The anterior cingulum is present but poorly developed, not uniting to form a complete buccal and posterior cingulum. A greatly reduced paraconid appears in occlusal view as a small sub-horizontal spur. The metacristid and hypocristid are roughly oblique to the long axis of the dentary. The cristid obliqua extends from the hypoconid to the posterior wall of the trigonid, intersecting the trigonid at a point well buccal to the point directly below the tip of the protoconid. There is a very small, broadly rounded entoconid. From the base of the metaconid posteriorly, the talonid endoloph follows the line of the dentary to the entoconid, but with a buccal orientation, until reaching the base of the hypoconulid.

M2: In M2, the talonid is slightly wider than the trigonid. The anterior and posterior cingula are weak as in M1 and the buccal cingulum is incomplete. The paraconid is well developed and is the smallest main trigonid cusp. The entoconid is moderately developed and blade-like. The cristid obliqua extends from the hypoconulid to the posterior wall of the trigonid, intersecting the trigonid at a point directly below the tip of the protoconid but well buccal to the metacristid fissure. The hypocristid extends from slightly anterior and buccal to the hypoconulid to the tip of the hypoconid. From the base of the metaconid posteriorly, the endoloph follows a line of the dentary as in M1.

M3: In M3, the trigonid is just wider than the talonid. A prominent parastylid wraps around the hypoconulid of M2. The anterior cingulum on M3 is slightly stronger than that in M2, and the buccal cingulum is incomplete and posterior cingulum weak. The paraconid is well developed and the smallest main trigonid cusp. The entoconid is moderately developed and subequal with the entoconid of M2. The cristid obliqua extends from the hypoconulid to the posterior wall of the trigonid, intersecting the trigonid at a point directly below the tip of the protoconid but well buccal to the metacristid fissure. From the base of the metaconid posteriorly, the endoloph of M3 follows a line of dentary with no lingual swelling.

M4: In M4, the trigonid is wider than the talonid. The anterior cingulum is as in M2; the buccal cingulum is absent; the posterior cingulum is absent. The metaconid is slightly taller than the paraconid, and both are much shorter than the protoconid. The weak hypoconid of the M4 talonid is greatly reduced and indefinable. The entoconid is present but minute and broadly rounded. The cristid obliqua forms a low, weak crest which contacts the trigonid wall slightly lingual of the metacristid fissure. A notable feature of M4 morphology is the reduction of the talonid crown enamel and absence of buccal cingulum below the cristid obliqua, which causes the talonid to appear as a narrow spur jutting off the trigonid wall. From the base of the metaconid posteriorly, the endoloph of M4 exhibits greater buccal orientation away from the line of the dentary compared with any other lower molar.