Coccymys kirrhos, Voss & Meng & Prendini & Voss & Whiteley & Knight & Lunde & And & Melomys & Bulletin, 2009

Voss, Musser Scientific Publications Of The American Museum Of Natural History American Museum Novitates Bulletin Of The American Museum Of Natural History Anthropological Papers Of The American Museum Of Natural History Publications Committee Robert S., Meng, Chair Board Of Editors Jin, Prendini, Paleontology Lorenzo, Voss, Invertebrate Zoology Robert S., Whiteley, Vertebrate Zoology Peter M., Knight, Anthropology Managing Editor Mary, Lunde, And, New Guinea Coccymys, Melomys & Bulletin, Albidens Amnh, 2009, Systematic Reviews Of New Guinea Coccymys And ‘‘ Melomys’ ’ Albidens (Muridae, Murinae) With Descriptions Of New Taxa, Bulletin of the American Museum of Natural History 2009 (329), pp. 1-139 : 1-139

Coccymys kirrhos , new species

HOLOTYPE AND TYPE LOCALITY: The holotype is AMNH 158175, an adult male collected by Hobart M. Van Deusen (original number 12256) on May 29, 1953. The specimen consists of a stuffed museum study skin, cranium, mandible, and partial postcranial skeleton. The skin and skull are in good condition (figs. 7, 29); incisors and molars are intact; the molars are worn but occlusal patterns of their cusps remain evident. External, cranial, and dental measurements are listed in table 7. Coronal patterns of maxillary and mandibular molar rows of a different specimen from Mt. Dayman are shown in figures 11 and 12.

The type locality is ‘‘Top Camp’’ (09 ° 499S,149 ° 169E), 2230 m, north slopes of Mt. Dayman, Maneau Range (also spelled ‘‘Maneao’’) at the eastern end of the Owen Stanley Ranges, Milne Bay Province, eastern Papua New Guinea (locality 22 in gazetteer and fig. 2). The camp ‘‘was on the western bank of the Atairo in a secluded grassy hollow within quarter of a mile of the head of that stream, and 1 K to 2 miles northwest of the summit of Maneau Peak’’ ( Brass, 1956: 126). In addition to ‘‘Mount Dayman,’’ the camp name, and altitude, recorded on specimen labels is the notation ‘‘Maneau Range,’’ which in this case is basically synonymous with Mt. Dayman. The latter is actually a part of the Owen Stanley Ranges and, as Brass (1956: 111–112) noted, has four primary summit peaks (Maneau, Gadmarau, Mana-man, and Dayman), grouped around the head of the Gwariu Valley that are all parts of one large mountain. The entire Mt. Dayman with its peaks, and the section of the Owen Stanley Ranges dominated by the mountain was called the Maneau Range by early explorers, after Maneau Peak, which is only one, and not the highest of the four peaks. ( Flannery and Groves, 1998, have also used ‘‘Nanneau Range’’ for this area.) Another perspective of the region is provided by Engilis and Cole (1997: 1), who worked there in 1985 and wrote that Mt. Dayman ‘‘is one of three isolated mountain peaks that dominate the extremity of the eastern peninsula of New Guinea. Viewed from the air, the summit is actually the apex of a complex series of dissected ridges. All but the summit alpine grasslands are covered in dense forest. Human settlements are in valleys below 1600 m; most are isolated by steep ridges.’’

REFERRED SPECIMENS: Six additional specimens. Four were collected in Milne Bay Province in the Maneau Range. Two are from the type locality and were obtained by Hobart Van Deusen at the top camp, 2330 m: the stuffed skin and the skull of an adult female (AMNH 158173) collected May 25, 1953, and the stuffed skin and nearly complete skeleton of a young adult male (AMNH 158174) collected May 28, 1953. The third specimen is an adult female (BBM-NG 109165) represented by a stuffed skin and a skull collected February 26, 1985 from the southeastern ramparts of Mt. Dayman on the Garatin Ridge in the Agaun region of the Maneau Range at Dumae Creek , 2.3 km N, 0.4 km W of Agaun (09 ° 539S, 149 ° 239E; Dumae Creek , the base camp for the expedition recounted by Cole et al. [1997], is below Garitin Pass, on the road from Agaun to Bonenau), 1525 m. The fourth specimen from the Maneau Range is a young adult (BBM-NG 184493) consisting of a body in fluid and extracted skull collected February 25, 2003, on the north slopes of Mt. Simpson , 0.5 km S of Bunisi Village (10 ° 019S, 149 ° 359E), ‘‘Camp 5,’’ 1490 m .

The fifth example is an adult female (BBM-NG 96950) represented by a skull and stuffed skin collected August 2, 1968, from Smith’s Gap (08 ° 039S, 146 ° 539E), ‘‘in the vicinity of Guari,’’ 2500 m, Central Province.

The sixth specimen is the skull and stuffed skin of an adult female (BBM-NG 55824) obtained November 2, 1967, from the Wau area, Bulldog Road, ‘‘ 12 mi from’’ Edie Creek (07 ° 319S, 146 ° 409E), 2500 m, Morobe Province.

DIAGNOSIS: The small-bodied and long-tailed Coccymys kirrhos is physically similar to Coccymys ruemmleri and C. shawmayeri , but contrasts sharply with both of those species by the bright orange-brown or tawny fur clothing upperparts of its head and body (dark brown to blackish brown in C. ruemmleri , brown in C. shawmayeri ) and by its whitish gray ventral coat (whitish gray through dark grayish white to dark buffy gray in C. ruemmleri , whitish gray to grayish white in C. shawmayeri ). The very long tail of Coccymys kirrhos relative to head and body length, and lack of a white tip on every specimen in the sample, is distinctive. Relative length of tail is much shorter in C. ruemmleri , proportionally similar in C. shawmayeri ; individuals with a white-tipped tail occur in 11% of the sample of the former and 76% of the latter (tables 3, 8). The skull and molars of C. kirrhos are appreciably smaller compared with C. ruemmleri (values for every dimension measured are less except for breadth of mesopterygoid fossa, which exceeds that in the sample of C. ruemmleri ; tables 4, 6, 12), and only a few of the cranial and dental variables measured match or exceed those for the average larger skull of C. shawmayeri (tables 4–6). Significant proportional differences in cranial and dental variables also distinguish C. kirrhos from the other two species of Coccymys .

GEOGRAPHIC DISTRIBUTION: Known only from lower montane to mid-montane forests in the Central Cordillera extending through the eastern peninsula of Papua New Guinea (fig. 2). Five of the seven known specimens are from Mt. Dayman, the adjacent Agaun region, and Mt. Simpson, all part of the Maneau Range, at the eastern end of the Owen Stanley Ranges. The westernmost record is the single specimen from Bulldog Road in the Wau area on the flanks of the Kuper Range at the western end of the eastern peninsula. The only record between those geographic brackets is the individual from Smith’s Gap near Mt. St. Mary, just west of the Wharton Range. Coccymys kirrhos likely occurs elsewhere in montane forest formations in other parts of the eastern peninsular Cordillera, but much of that region has been poorly sampled for small mammals.

The altitudinal records for samples from the Maneau Range extend from 1490 m to 2230 m; 2500 m is the altitude at which the specimens from Bulldog Road and Smith’s Gap were taken (table 13). The range of altitudes encompasses lower montane and mid-montane forest formations. Unlike the other two species of Coccymys , C. kirrhos has not been collected in upper montane habitats or alpine landscapes, and the species occurs at lower altitudes than have been recorded for either C. ruemmleri (2200 m) or C. shawmayeri (1600 m); see table 13.

ETYMOLOGY: The Greek kirrhos means ‘‘orange-yellow’’ or ‘‘tawny,’’ which describes the bright dorsal pelage of Coccymys kirrhos compared with the dark and somber coat of C. ruemmleri and the warm brown upperparts of C. shawmayeri .

DESCRIPTION AND COMPARISONS: Coccymys kirrhos , C. ruemmleri , and C. shawmayeri have small bodies and long tails relative to length of head and body (table 3). They also agree, except for size, in their short muzzles, shapes of ears and feet, relative lengths of mystacial and other vibrissae, number of palmar and plantar pads and their extent relative to palmar and plantar areas, configuration of scale annuli on the tail, number and relative lengths of hairs emerging from beneath each tail scale, unpigmented claws, and number of teats—in these respects, C. kirrhos is essentially a somewhat smaller physical version of C. ruemmleri and C. shawmayeri . The two latter species contrast sharply in coloration of fur with C. kirrhos . The dorsal coat of C. kirrhos is soft and thick, much as it is in C. ruemmleri and C. shawmayeri , but averages shorter (8–10 mm long as opposed to 11–14 mm in C. ruemmleri and 10–12 mm in C. shawmayeri ), and is bright orange-brown or tawny from the rump to the top of the head and cheeks, becoming more ochraceous on the sides of the body (overhairs are gray for most of their lengths, with bright buff to ochraceous buff tips); only the face between the eyes is gray (a somber dark brown and burnished highlights characterize the upperparts of most C. ruemmleri , with a few specimens even suffused with black; brownish gray with burnished highlights is characteristic of C. shawmayeri ). Prominent brownish black encircles each eye and covers the bases of the mystacial vibrissae, a pattern resembling that of the other two species, but their faces and cheeks are gray, while only the face between the eyes is gray in C. kirrhos , and its cheeks are tawny. As in the other two Coccymys , the dorsal surfaces of the front and hind feet as well as digits of C. kirrhos are scantily covered with pale brown or unpigmented hairs, but the metacarpal and metatarsal surfaces are paler. The underparts of C. kirrhos , from chin to base of tail, are bright whitish gray (hairs are gray basally, but the white distal segment is long, producing a denser white overlaying the gray); the range in C. ruemmleri extends from whitish gray through dark grayish white tones to dark grayish buff ventral coats; whitish gray to grayish white is typical in our sample of C. shawmayeri .

A long tail relative to length of head and body (LT/LHB 5 150%–181%, N 5 7) is characteristic of C. kirrhos , and similar proportions occur in samples of C. shawmayeri (145%–170%, N 5 33). However, in samples of C. ruemmleri from the Snow and Star mountains, the tail is relatively much shorter (140%–146%, N 5 33); see table 3. The tail averages paler in C. kirrhos (grayish brown) than in C. ruemmleri (brown), and generally matches C. shawmayeri in chromatic range. As in the other two species, C. kirrhos exhibits a comparable linear calloused strip devoid of hairs and scales on the dorsal surface along the terminal fifth of the tail. Not one of the seven examples of C. kirrhos has a white tail tip, which is more comparable to the pattern seen in most specimens of C. ruemmleri (6 of 55 exhibit a white segment, 11%), but unlike our samples of C. shawmayeri in which the majority of the specimens have a tail with some measure of white at the tip (38 of 50 individuals, 76%); see table 8.

Body mass is less in C. kirrhos compared to either C. ruemmleri or C. shawmayeri . The adult female C. kirrhos from the Garatin Ridge weighed 22.5 g. Hobart Van Deusen obtained weights for the three from Mt. Dayman as 0.75, 0.9, and 1.0 ounces, which converts to 22, 26, and 28 g. Values for mass are available for 16 adults from the eastern slopes of Mt. Wilhelm. All were handled by Van Deusen who recorded weights in ounces, which we converted to grams: mean and standard deviation 5 32.9 ± 6.65 g, range 5 22.7–45.4 g. A single example of C. ruemmleri from the Star Mountains weighed 34 g. The mean, 24.6 ± 2.87 g, and range, 22–28 g, of the four C. kirrhos are much less, paralleling its average smaller body size and other variables.

Contrasts between C. kirrhos and the other two species of Coccymys in cranial and dental variables are quantitative, not qualitative, and involve differences in absolute size and proportions, which are presented as tabular and graphic results from univariate and multivariate analyses derived from the population samples listed in table 3 and the single specimens tabulated in table 6.

In absolute size, Coccymys kirrhos averages smaller than C. ruemmleri in breadth of incisive foramina and first upper molar, is markedly smaller than that species in nearly all of the other cranial and dental dimensions that were measured, and exceeds any sample of C. ruemmleri in breadth of mesopterygoid fossa—quantitative contrasts that are evident in tables 4 and 6 and in figure 29.

Coccymys kirrhos is closer to C. shawmayeri in measures of cranial and dental dimensions. Lengths of rostrum and bony palate, and breadth of first upper molar are comparable in the two species, the mesopterygoid fossa and incisive foramina average wider in C. kirrhos , and all the other cranial and dental variables either average less or are appreciably smaller in that species compared with C. shawmayeri (tables 5, 6).

Proportional morphometric differences between AMNH samples of C. kirrhos and the other two species have been summarized by the patterns of covariation in cranial and dental variables reflected in graphs of specimen scores projected onto the first and second canonical variates extracted from discriminant-function analysis (fig. 4) and discussed in a previous section.

These proportional contrasts—and similarities—can also be visualized in ratio diagrams. The first diagram focuses on distinctions between the type series of C. kirrhos from Mt. Dayman and the population sample of C. ruemmleri from Lake Habbema, the type locality of that species (fig. 30; see also tables 4 and 6). Compared with the sample of C. ruemmleri from Lake Habbema, C. kirrhos is significantly narrower across the zygomatic arches relative to skull length or breadth of braincase, has a narrower interorbit relative to any other variable, longer bony palate relative to length of diastema and postpalatal region, wider mesopterygoid fossa relative to any other measured dimension, wider incisive foramina relative not only to their lengths but to many of the other variables, and wider first upper molars relative to length of molar rows (the wider molar is apparent in fig. 8 where molar rows of C. ruemmleri and C. kirrhos are compared). These are the striking contrasts; other proportional differences and similarities can be gleaned from the ratio diagram.

The second ratio diagram (fig. 31; check also tables 5, 6) contrasts the type series of C. kirrhos from Mt. Dayman with the AMNH population sample of C. shawmayeri from Mt. Wilhelm, the nearest geographic sample we have that is closest to the collection site of the holotype of shawmayeri (see gazetteer). Some of the proportional contrasts graphed here between C. kirrhos and C. shawmayeri also apply to C. kirrhos and C. ruemmleri (fig. 31): compared with C. shawmayeri , the type series of C. kirrhos is narrower across the zygomatic arches relative to skull length or breadth of braincase, has a narrower interorbit relative to any other variable, longer bony palate relative to length of diastema and postpalatal region, wider mesopterygoid fossa relative to any other measured dimension, and wider incisive foramina relative not only to their lengths but to many of the other variables. Other proportional distinctions apply only to C. kirrhos and C. shawmayeri : C. kirrhos has a longer rostrum relative to its breadth or length of skull, and smaller bullae relative to skull length or size of braincase. Finally, where C. kirrhos has wider first upper molars relative to length of molar rows compared with C. ruemmleri , no proportional difference between C. kirrhos and C. shawmayeri exists in these dental variables.

IDENTIFICATION OF BBM SPECIMENS: We know of only seven specimens of Coccymys preserved in museums of the world that have tawny dorsal pelage and whitish gray underparts. Three are in the American Museum of Natural History and comprise the type series of C. kirrhos from the Maneau Range; four are stored in the Bishop Museum. Two of those four were collected in the Maneau Range (Dumae Creek and Mt. Simpson), the eastern ramparts of the Owen Stanley Ranges, but the other two come from the western segment of the Owen Stanley Ranges, one from Smith’s Gap and the other from Bulldog Road in the Wau area. Coccymys shawmayeri has also been collected at Bulldog Road, and on Mt. St. Mary, which is just east of Smith’s Gap. Are these two tawny individuals C. kirrhos or simply examples of C. shawmayeri with orange-brown upperparts? If they are C. kirrhos , they not only document the westernmost collection localities of that species but also rather extensive sympatry between it and C. shawmayeri ; if they are tawny C. shawmayeri , they demonstrate one of two chromatic expressions of the dorsal fur within that species, a dimorphism not seen in the other two species of Coccymys .

To answer the question, we subjected cranial and dental variables to a series of principal components analyses in which the seven tawny individuals were compared with samples of C. shawmayeri in different combinations. We first compared the type series of C. kirrhos and the four tawny BBM specimens with our samples of C. shawmayeri , all possessing brown dorsal pelage, from the Telefomin area, Mt. Hagen, Mt. Wilhelm (including the holotype), Bulldog Road in the Wau area, and Mt. St. Mary. The pattern of covariation in cranial and dental variables among these specimens is summarized in the scatter plot of specimen scores projected onto the first and second principal components in figure 32. The spread of scores along the first axis conforms to a group of seven specimens on the left, all with tawny dorsal fur, and a larger cluster on the right representing specimens of C. shawmayeri , and containing the holotype, all showing brown upperparts. Difference in size is the primary factor expressed on the first principal component with most of the variables influencing the spread of points (table 17). The tawny individuals are smaller than most of those in samples of C. shawmayeri , a contrast also reflected in summaries of univariate statistics (tables 5, 6) and the ratio diagram (fig. 31). The specimen from Dumae Creek, which is near Mt. Dayman, and the animal from Mt. Simpson, cluster with the type series of C. kirrhos , which is expected—all are from the Maneau Range. The score for the tawny specimen from Bulldog Road sits nearly on top of that representing the holotype of C. kirrhos and far from the two points for the brown-furred individuals also collected at Bulldog Road, which nest deep within the C. shawmayeri cluster (six brown-furred speci-

TABLE 17 Results of Principal Components Analysis of Geographic Samples of Two Species of Coccymys Samples of Coccymys shawmayeri from the Telefomin area, Mt. Hagen region, Bismarck Range, Bulldog Road in the Wau area, and Mt. St. Mary are compared with samples of Coccymys kirrhos from the Maneau Range, Smith’s Gap, and Bulldog Road in the Wau area. (Principal components are extracted from a covariance matrix of 18 log-transformed cranial and dental variables; see tables 5–7, fig. 32.)

mens come from Bulldog Road but only two are adults that could be used for the analysis). Of the seven tawny scores, that for the specimen from Smith’s Gap is closest to the larger constellation of points, but still far from any of the of the seven scores representing the sample from Mt. St. Mary, which is geographically close to Smith’s Gap. Tawny upperparts as a distinguishing trait for C. kirrhos seems to be supported in this analysis.

A second principal components analysis compared the seven individuals possessing tawny dorsal coats with a set of C. shawmayeri composed of the seven specimens from Mt. St. Mary, the two from Bulldog Road, and the holotype. Would the tawny individuals from Bulldog Road and Smith’s Gap still associate with C. kirrhos when the effect of larger samples of C. shawmayeri was removed? The pattern of specimen scores projected on the first and second principal components exhibits two discrete clusters, one consisting of all seven tawny animals, the other composed of C. shawmayeri (fig. 33A). Size again is the primary dividing factor, with nearly all variables spreading the scores into two clusters along the first principal component (table 18). The score for the tawny rat from Bulldog Road continues to be isolated from the two brown-furred individuals from Bulldog Road, and the point representing the rat from Smith’s Gap associates more closely with C. kirrhos than with the sample from Mt. St. Mary.

The third analysis employed the same examples of C. shawmayeri but restricted the tawny-furred sample to the specimens from Bulldog Road and Smith’s Gap to determine if they would separate from C. shawmayeri by themselves; here any effect of the five C. kirrhos from the Maneau Range would be eliminated. The projection of specimen scores on first and second principal components resulted, for the third time, in a large cluster containing the scores for the holotype of shawmayeri , the sample from Mt. St. Mary, and the two brown-furred individuals from Bulldog Road; this cluster is isolated from the two specimens with tawny upperparts (fig. 33B). The tawny animal from Bulldog Road does not clump with the other two from there, and the specimen from Smith’s Gap does not nest with the sample from Mt. St. Mary. Separation of the two groups along the first axis again reflects the larger cranial and dental dimensions of C. shawmayeri compared with the smaller size of the two tawny individuals, and nearly all variables contribute to this dispersion of scores along the first axis (table 18).

These multivariate analyses—combined with tawny dorsal coats, whitish gray underparts, long tails relative to head and body, and tails without white tips—identify the specimen from Bulldog Road and the one from Smith’s Gap as examples of C. kirrhos , and not C. shawmayeri . They document not only the westernmost records for C. kirrhos but also regional sympatry between that species and C. shawmayeri .

GEOGRAPHIC VARIATION: Our sample of C. kirrhos is inadequate to truly assess geographic variation in phenetic traits. All specimens have tawny upperparts, whitish gray underparts, and a relatively long tail without patterning at the tip. The individual from Bulldog Road and the specimen from Smith’s Gap have slightly thicker dorsal coats, more similar to the lengths in C. shawmayeri . Values for many cranial dimensions for those two specimens are also somewhat greater than recorded for the sample from the Maneau Range, and, of the two, the animal from Bulldog Road slightly exceeds the specimen from Smith’s Gap in 11 of the 18 cranial and dental dimensions measured (table 6). However, in multivariate space as revealed by principal components analysis, where both skull size and shape are expressed, the specimen from Bulldog Road is closely associated with the holotype of C. kirrhos in most of the analyses, and among all the specimens of C. kirrhos , the animal from Smith’s Gap, while still part of the C. kirrhos cluster, is the closest to samples of C. shawmayeri (figs. 32, 33A, B). Larger samples of species from more localities than those currently available are required to determine geographic variation in phenetic characters and its significance.

HABITAT: During the middle of May 1953, members of the Fourth Archbold Expedition to New Guinea were ascending the northern flanks of Mt. Dayman to establish their top camp at 2230 m. From their number 2 camp at 1550 m, Brass (1956: 110–111) describes traveling along ridges through what he called mid-mountain forests (tropical lower montane rainforest in Whitmore’s, 1984, terminology) of chestnut ( Castanopsis ), oaks ( Lithocarpus ), walnut ( Engelhardtia ), and species of Gordonia, Sloanea , and other genera. At 1800 m,

the mid-mountain forest gave place to beech ( Nothofagus ) forest, the new dominants being easily recognizable by their large size, massive branches, dense foliage of small leaves, and rough dark bark. Thereafter, for two hours, the trail led through tall beech forest, usually very open underneath and with little leaf litter or moss. … At 2050 meters the first ‘‘hoop-pines’’ ( Araucaria ) far overtopped all other trees on the crest of the spur. … At 2060 meters we rested in especially fine tall beech forest on the first sizable bit of fairly level ground seen on the mountain [see plate 14, fig. 2 in Brass, 1956, for photograph of this spot; also fig. 34 here]. … At 2150 meters the edge of the forest was reached after a stiff climb that took us out of the beech zone and into what I … have called mossy forest, and, coming out abruptly into intense sunshine on bracken-covered slopes, we surveyed a depressing spectacle of fire damage and destruction. The crest and upper slopes of the spur had been almost completely deforested. Gray stands of hundreds of very tall, straight Araucaria trees, killed by fire, edged the surviving forest in ravines on either side. … From the 2310-meter high point on the trail, where the view took in several square miles of

TABLE 18 Results of Principal Components Analysis of Geographic Samples of Two Species of Coccymys Graph A : samples of Coccymys shawmayeri from Bulldog Road in the Wau area and Mt. St. Mary are compared to samples of Coccymys kirrhos from the Maneau Range, Smith’s Gap, and Bulldog Road; holotypes of shawmayeri and kirrhos are included. Graph B: samples of Coccymys shawmayeri from Bulldog Road, Mt. St. Mary, and the holotype of shawmayeri is contrasted with the two Coccymys kirrhos from Smith’s Gap and Bulldog Road. (Principal components are extracted from a covariance matrix of 18 log-transformed cranial and dental variables; see tables 5–7, fig. 33.)

terrain above the 2200-meter level, including Maneau Peak and the head of the Gwariu River Valley, … the upper parts of the whole mountain had been greatly altered by the burning of forests which must formerly have occupied all but a small fraction of the total area. Extensive forests remained, but for the most part on the more sheltered slopes and in strips in deep ravines. Grasslands of oldestablished appearance occupied much of the denuded ground, while bracken … and other ferns, or a mixture of fern and grass, provided the cover on slopes which at least in some instances plainly had not been so long deforested [fig. 35].

The top camp was finally established at 2230 m on a flat in a deep, sheltered, grassy hollow on the western bank of the Atairo within a quarter of a mile of the head of that stream, and 1.5 to 2 miles (2.423.2 km) northwest of the summit of Maneau Peak. The flat was bounded on one side by a slope covered with grass and bracken, and on the other side by the Atairo stream edged with mossy forest, which also covered the adjacent slope (figs. 36, 37). ‘‘Mossy forest’’ is the way Brass (1956: 128) described the forest formations everywhere on Mt. Dayman above the beech zone (1800–2150 m), providing a superb description of the ‘‘mossy forest’’ and its floristic component, both on exposed ridges and slopes of ravines, and also noted the tall lowland tropical emergents found in sheltered ravines up to the altitude of the camp.

Thirty-three days were spent at the top camp, and few ‘‘were without mist, which drifted up from lower levels very often by mid-morning and tended to clear off before nightfall’’ ( Brass, 1956: 126). Mean maximum ambient temperature recorded for 29 days (May 22 to June 19) was 21.3 ° C (extremes, 18.5–24.5 ° C); mean minimum for 30 days (May 21 to June 19) was 5.1 ° C (extremes, 0–11 ° C).

The mosaic of grassland and mossy forest is reflected by the habitat surrounding the top camp, nestled as it was between those two botanical formations, and in notes associated with the three specimens from 2230 m. The holotype of C. kirrhos was trapped in ‘‘Herbaceous forest margin. Fallen trees and Gunnera ’’; of the other two, AMNH 158174 was taken along the ‘‘Forest edge,’’ and AMNH 158173 was caught in ‘‘grassland’’ (notations on the skin tags and in Van Deusen’s field catalog). In his summary of mammals obtained by Van Deusen, Brass (1956: 129) singled out the ‘‘beautiful little Pogonomelomys [5 C. kirrhos ] … that was found in the ‘‘shrubby forest fringe.’’ Van Deusen did not record whether the three were taken near camp or farther afield. Because much of the grass- and bracken-dominated slopes are anthropogenic in origin, and, as noted by Brass (1956: 111), forest must have occurred over most of the total area on Mt. Dayman, even up to altitudes just below the summit, we can reasonably assume that C. kirrhos is primarily a forest inhabitant, an observation supported by data associated with the specimen from the Garatin Ridge, on the southeast ramparts of Mt. Dayman in the Agaun area.

The specimen from the Garatin Ridge (reported as C. ruemmleri ) was encountered in primary forest, and caught ‘‘in a live trap set on the forest floor’’ ( Cole et al., 1997: 12). ‘‘The forest on Garatin Ridge between 1,400 and 1,600 m,’’ reported Engilis and Cole (1997: 3–4),

is transitional in nature, being composed of dominant plants and physiognomic components of both mid-montane and lower montane forest as described by Johns (1982). Some of the dominant (i.e., tallest) canopy trees documented were Prumnopitys ( Podocarpaceae ), Lithocarpus and Nothofagus ( Fagaceae ), Metrosideros ( Myrtaceae ), and Garcina ( Clusiaceae ). Emergent Araucaria ( Araucariaceae ), observable at long distances formed small scattered groves along the ridges. … The forest in this area [which includes the nearby base camp at Dumae Creek, 1525 m] was composed of four distinct canopy layers. … The height of the primary layer averaged 46 m. Canopy emergents uncommonly exceeded 50 m. The subcanopy was composed of two distinct layers; the upper averaged 18 m, the lower 7.4 m. The ground layer varied according to exposure but averaged 1.1 m. The surface of the canopy, as viewed from the air, revealed an uneven but continuous cover.

Engilis and Cole summarized these forest characteristics in a diagram of the ‘‘Typical primary rainforest phsiogonomy at Dumae Creek, 1,525 m elevation.’’ It rained every day for the duration of the stay at the Dumae Creek camp, from February 25 to March 20. Total rainfall during this period was 333 mm with maximum rainfall (in a period of 24 hours) of 42 mm. Average high and low ambient temperatures were 21 ° C (extremes, 19–25 ° C) and 15.7 ° (extremes, 13–19 ° C).

The specimen from the north slopes of Mt. Simpson, 0.5 km S of Bunisi Village at 1490 m (‘‘Camp 5’’), was collected in a pitfall by Fred Kraus on February 25, 2003. Fred (in litt., 2008) wrote us this about his recollections of the site:

I would call the locality primary rainforest, but it was slightly disturbed in the sense that there were a couple of footpaths running through the area and there were some gardens in the nearby vicinity. It was a short walk from this forest to more clearly secondary habitats, and it was only 0.5 km from the nearest village, but the immediate forest where the Coccymys came from was pretty nice itself. The forest would fit the category of lower montane forest of Paijmans. Because all the rodents I pickled from that site were collected in bucket traps set along drift fences, I can’t provide you with any more specific habitat notes that would shed light on the critter’s habits, other than to note that they were active at night.

BIOLOGY: Coccymys kirrhos certainly spends time on the ground, as the trapping records attest, and we suspect it, like C. ruemmleri , is also scansorial, able to scamper along limbs and woody vines in the forest understory. The rat is most likely active during the night (as Fred Kraus indicated above). Because of its close resemblance to C. shawmayeri in proportions of hind feet and tail relative to body size; in cranial and mandibular conformations; in shape of incisors, their size relative to the skull and mandible, and extent of enamel; and in occlusal patterns of upper and lower molars, we infer that the diet of C. kirrhos is probably also similar, consisting of fruit, seeds, and insects. Stomach contents from the specimen caught on Mt. Simpson contained a suspension of macerated fruit pulp and seed coats (table 16). All other aspects of its biology are unknown.

One population aspect of C. kirrhos requires investigation. The species may be either uncommon or difficult to trap if our sample is an indication of its relative abundance in nature. Coccymys shawmayeri , by contrast, seems to be common in certain

TABLE 19

Specimens of Coccymys kirrhos and Coccymys shawmayeri in the Bernice P. Bishop Museum from Bulldog Road in the Wau Area, Morobe District, Papua New Guinea a

C. kirrhos (tawny upperparts, no white tail tip)

F, ad; 55824; 11–2–1967; ‘‘ 12 mi from Edie Creek,’’ ‘‘2500 ± m’’; P.H. Coleman

C. shawmayeri (brown upperparts, all with white-tipped tails)

F, juv; 96646; 6–18–1968; ‘‘ 12 mi from Edie Creek,’’ ‘‘2400 ± m’’; A.B. Mirza

F, juv-ya; 96802; 6–18–1968; ‘‘ 12 mi from Edie Creek,’’ ‘‘2400 ± m’’; A.B. Mirza

F, ad; 61669; 9–10–1968; ‘‘ 12 mi from Edie Creek,’’ ‘‘2400 ± m’’; A.B. Mirza

M, ad; 101267 b; 7–17–1972; ‘‘12 ± mi S Edie Creek,’’ ‘‘2500 ± m’’; A.B. Mirza

F, ad; 101502; 8–4–1972; ‘‘12 ± mi S Edie Creek,’’ ‘‘2500 ± m’’; A.B. Mirza

M, juv; 29140; 5–19–1967; ‘‘32 road km [20 mi] S Wau,’’ ‘‘2400 ± m’’; J.L. Gressitt a

Sex, age, catalog number (BBM-NG), date of collection, location on Bulldog Road, altitude, and collector are provided for each specimen. Except for relative age, which we determined, all information was transcribed from labels attached to the specimens.

b

BBM-NG

101267 is a skeleton only without notes on tail pattern.

habitats, judged by the large samples from particular mountains—Mt. Hagen and Mt. Wilhelm, for example (see gazetteer). One comparison is illustrative. Hobart Van Deusen obtained only three C. kirrhos during the month the Archbold Expedition worked at the ‘‘Top Camp’’ on Mt. Dayman in the Maneau Range, and members of the expedition (documented by Cole et al. 1997) camped for nearly a month at Dumae Creek in the Maneau Range, procuring only a single C. kirrhos . During a roughly similar period of time on Mt. Wilhelm, 29 specimens of C. shawmayeri were caught between the high Lake Aunde camp and the lower Pengagl Creek camp where the Archbold Expedition worked. The interplay of other factors—environmental, trapping techniques, and the frequency with which local people contributed to the inventories—may, of course, be responsible for the discrepancy in sample sizes, and to announce that C. kirrhos is uncommon in nature relative to C. shawmayeri (and C. ruemmleri , which is documented by large samples from the Snow and Star mountains; see gazetteer) is admittedly simplistic, but identifies an aspect of its population biology that should be studied.

SYMPATRIC ASSOCIATIONS: Here we discuss first the sympatry between C. kirrhos and C. shawmayeri , then the sympatric association of C. kirrhos with other species of mammals collected in the Maneau Range, primarily those obtained along the Mt. Dayman transect worked by members of the Fourth Archbold Expedition.

Sympatry between the two species of Coccymys . Seven specimens are available from Bulldog Road, south of Edie Creek, or nearby Wau (table 19). The example of C. kirrhos was collected in 1967 ‘‘ 12 mi from Edie Creek,’’ as was a specimen of C. shawmayeri obtained from 20 mi south of Wau. Other C. shawmayeri were taken in 1968 and 1972 from either ‘‘ 12 mi from Edie Creek,’’ or ‘‘ 12 mi S Edie Creek,’’ approximately the same area. Examples of the two species were collected at about the same place but at different times. Bulldog Road south of Edie Creek and Wau deserves additional surveys to determine the microhabitat and other relationships between the two species of Coccymys there.

The specimen of C. kirrhos from Smith’s Gap (2500 m) provides the other record of regional sympatry. Smith’s Gap is not far from the southwestern slopes of Mt. St. Mary (‘‘SSW Mt. St. Mary,’’ 3000 m), the source of seven C. shawmayeri . All were collected by A.B. Mirza who trapped the specimen from Smith’s Gap in August 1968, and the series from Mt. St. Mary during July of the same year. Additional mammalian surveys in this region would certainly be welcome and might provide answers to questions unanswerable with present data. For example, are the two species separated altitudinally in this area or do they occur at the same place? Are there any broad habitat or microhabitat distinctions between the two?

The highlands between Mt St. Mary and Mt. Victoria, an area that also embraces the Wharton Range, are one region where surveys of small mammals, particularly rodents, are sorely needed. If Mt. St. Mary is the easternmost occurrence of C. shawmayeri , the eastern C. kirrhos should be found in suitable habitats throughout the mountains. On the other hand, C. shawmayeri may be the Coccymys living in upper montane forest and alpine grassland between Mt. St. Mary and Mt. Victoria, and C. kirrhos may occur syntopically with C. shawmayeri or be confined to lower montane forest formations at lower altitudes. Visits by biologists to the Wharton Range and surrounding highlands have largely consisted of bird collecting (for example, Archbold and Rand, 1935) and incidental notes on a few mammals connect- ed with a nonforest vegetation survey (Hope, 1975).

Sympatry along the Mt. Dayman transect. The three examples of C. kirrhos from Mt. Dayman were collected on the Fourth Archbold Expedition in 1953 ( Brass, 1956). Between May and September 1953, six camps were established along a transect from the coast at Baiawa, Moi Biri Bay, to the ‘‘Top Camp,’’ at 2230 m on the northern slopes of Mt. Dayman. Their locations and elevations are indicated in figure 38, which is a reproduction of the original map of the area published in the expedition summary ( Brass, 1956).

Collection activities through this transect resulted in 1043 specimens of mammals representing 59 indigenous species of echidna, bats, marsupials, and rodents. The number of specimens of each species collected at different altitudes is summarized in figure 39. We identified all the material and employed current taxonomic designations (see Helgen, 2007c and references cited there) with a few exceptions. We do not, for example, recognize Van Dyck’s (2002) genus Murexechinus and employ the usage of Murexia , following Krajewski et al. (2007). We also realize that future revisionary studies will modify some of the current names, reflecting new systematic revisionary work. Helgen (2007c), for example, notes that what is now identified as Uromys anak from the Owen Stanley Ranges is likely a separate species; he also suggests that some of the species currently recognized—the marsupials, Phalanger gymnotis , Spilocuscus maculates , Petaurus breviceps , and the bat, Nyctimene albiventer — may actually be species complexes. We also excluded nonnative species from the chart (one Rattus exulans was caught at 30 m and 24 were taken at 2230 m at the ‘‘Top Camp’’), including dogs and pigs.

We are aware that members of the Archbold Expedition did not obtain samples of all the mammals living in the area. In 1952, Laurie reported on a collection of mammals made by F. Shaw Mayer in Papua New Guinea, where he worked between 1932 and 1949, and included the Maneau Range (Mt. Orian, Mt. Maneau, Mt. Mura, and Mt. Simpson) in his travels. While Shaw Mayer collected examples of some of the same species encountered by the 1953 Archbold Expedition to Mt. Dayman, he also obtained others not found by the Archbold survey, notably the marsupials Pseudochirulus canescens , Microperoryctes papuensis , Satanellus albopunctatus , and Murexia rothschildi . The Bishop Museum Expedition to Mt. Dayman, undertaken in 1985, obtained samples of the marsupials Murexia rothschildi , Microperoryctes ornata and M. papuensis , and Dorcopsis macleayi ; the bats Paranyctimene raptor and Rousettus amplexicaudatus ; and the rodents Mallomys aroaensis , Paramelomys platyops , Parahydromys asper , and Pogonomys loriae — none of these were collected along the Archbold Expedition’s transect. Recently, two other species have been added to the fauna of the Maneau Range: the moss mouse Pseudohydromys germani ( Helgen, 2005a) , and another new species of Pseudohydromys ( Helgen, 2007a) that is being described. Finally, Helgen (in litt., 2008) wrote us that other surveys in the general area have taken the tree kangaroo, Dendrolagus goodfellowi .

Compared with the total number of mammalian species recorded from the Maneau Range, the faunal representation of species documented by the Archbold survey is incomplete. However, the 59 species sampled by the Archbold Expedition do provide an altitudinal snapshot of the mammal fauna, of which Coccymys kirrhos is a member, along the northern slopes of Mt. Dayman and adjacent coastal lowlands in particular and in the Maneau Range generally. Seven species of marsupials, three species of bats, and seven species of rodents are recorded from 2230 m, the altitude where all three AMNH examples of C. kirrhos were taken.

Coccymys kirrhos is one more addition to the seven montane and three lowland species of marsupials, bats, and rodents that occur only on the southeastern peninsula of Papua New Guinea (Helgen, 2005, 2007a; Musser et al., 2008). These species signal that region, especially the montane areas, to be a realm of mammalian endemism, possibly a reflection of the past geological history of New Guinea when the southeastern peninsula was an island separated from the emergent western portion of New Guinea until the Pliocene ( Aplin et al., 1993; Flannery, 1995). There are likely other mammals currently regarded as subspecies peculiar to the southeastern peninsula that will be recognized as distinct species after taxonomic revision (see Helgen, 2007a) and these, possibly along with new discoveries, will help define the montane habitats in the Owen Stanley Ranges in particular and that mountainous backbone and bordering coastal lowlands in general as a special faunal unit.

The account of Coccymys kirrhos completes our review of species diversity in Coccymys . The next section will compare that genus with a unique murine that is endemic to the Snow Mountains of western New Guinea and is still represented by few specimens.

RECHARACTERIZATION OF ‘‘ MELOMYS ’’ ALBIDENS

Melomys albidens was characterized by Tate (1951: 286) as a ‘‘ Melomys differing sharply from all species except M. fellowsi by possession of white incisor teeth. From M. fellowsi it is distinguished by its much smaller size, and proportionately broader zygomata, larger bullae, shorter tooth row, and much narrower molars.’’ He went on to describe the species this way:

Pelage long and soft, above and below, the dorsal color near Wood Brown (Ridgway), with the hair bases fuscous; ventrally much paler brown, the bases of the hairs also fuscous. Ears large. Hands and feet whitish. Width of foot at base of fifth metatarsal, 4.4 mm. Tail lacking the Melomys - Uromys characters (which, however, are developed in the simple dentition), and instead showing the overlapping scale rings of

Rattus and scale hairs, three per scale, about three scale lengths. Skull with full braincase and well-expanded zygomatic arches, in combination with a narrow, somewhat elongate muzzle.

Interparietal wide (10 mm.). Nasals surpassed backwardly by the nasal processes of the premaxillae. Anterior part of frontals depressed.

Lacrimals large, prominent. Zygomatic plate very narrow, its anterior edge vertical to the notch, which is extremely shallow. Bullae large,

considerably larger than in the otherwise larger

Melomys fellowsi . Palate extending back to middle of M3, and provided with a blunt,

post-palatal spine. Pterygoid fossa rather wide (2.8 mm). Incisive foramina, which stand well in advance of the molars, only slightly shorter than the molar rows; the tooth rows in turn shorter than the bullae.

The species albidens was retained in Melomys for several decades after Tate (1951) described it ( Laurie and Hill, 1954, for example). Eventually Musser and Carleton (1993) treated albidens as a species of Coccymys simply to disassociate it from either Melomys or Pogonomelomys where it did not belong, and because so many of its anatomical traits are unlike species within those clusters, and some features more closely resemble those characterizing C. ruemmleri . This association had been noticed independently by other researchers. Flannery (1990: 240), for example, wrote how ‘‘Recent examination of the skull by the author suggests that it is more closely related to ‘ Pogonomelomys ’ ruemmleri than to any other New Guinean murid.’’ Menzies (1990: 127), in his revision of Pogonomelomys , which among other results provided a dendrogram estimating percent affinities among the taxa studied, noted that ‘‘ Pogonomelomys ruemmleri comes out with a close affinity (90% similarity) to Melomys albidens , an affinity which does not appear to have been noted in the literature, while these two species together have less than 50% similarity to any others.’’ Neither Flannery (1990) nor Menzies (1990) formally allocated albidens and ruemmleri to the same genus, but both later acknowledged this transfer (Flannery, 1995; Menzies, 1996). Our new comparisons indicate that traits associated with skins and skulls (no fluid-preserved examples of albidens exist) exclude albidens from the monophyletic cluster represented by the three species of Coccymys , and from any other previously identified monophyletic group of New Guinea murines. Its distinctive morphology and uncertain relationship are best expressed by placing albidens in its own genus.