Coendou pruinosus Thomas

VOSS, ROBERT S. & DA SILVA, MARIA N. F., 2001, Revisionary Notes on Neotropical Porcupines (Rodentia: Erethizontidae). 2. A Review of the Coendou vestitus Group with Descriptions of Two New Species from Amazonia, American Museum Novitates 3351, pp. 1-36 : 11-31

Coendou pruinosus Thomas

Figures 5B , 6B , 7 , 8

Coendou pruinosus Thomas, 1905: 310 .

Coendou (Sphiggurus) pruinosus: Tate, 1935: 307 (new name combination).

Coendou (Sphiggurus) vestitus pruinosus: Cabrera, 1961: 602 (new name combination).

Sphiggurus vestitus: Honacki et al., 1982: 572 (part; pruinosus treated as a junior synonym).

dou pruinosus and the new species described below.

NATURAL HISTORY AND CONSERVATION STATUS: Nothing has apparently been record­ ed about the habitats or behavior of this species, but the natural vegetation at the two localities where specimens are definitely known to have been collected was probably lower montane moist forest (bosque húmedo subtropical; Espinal and Montenegro, 1963). Unfortunately, habitat destruction is virtually complete in this part of Colombia (IAVH, 1998), and it is possible that the species has been extirpated. Apparently, no specimens or sightings have been recorded since 1925.

SPECIMENS EXAMINED: Colombia — Cundinamarca, Quipile ( AMNH 70529 ), San Juan

TYPE MATERIAL: The holotype , BMNH 5.7 .5.9, consisting of the skin, skull, and mandibles of an adult male collected by S. Briceño Gabaldón e hijos at 2500 m elevation in the Montañas de la Pedregosa near Mérida, Venezuela, on 14 January 1905. In addition, Thomas (1905) examined four paratypes, of which three retain original labels with Briceño’s commercial imprint: two of these are from ‘‘ Montaña del Valle 2600 m’’, and were collected on 16 November 1903 ( BMNH 5.7 .5.8, 5.7.5.11); the other is from ‘‘ Montañas del Tabay 2600 m’’, and was collected on 28 January 1904 ( BMNH 5.7.5.12). The fourth paratype ( BMNH 5.7.5.10) has a museum label in Thomas’s hand with the locality given as ‘‘ Merida, Venezuela’ ’, and the collection date as 14 June 1904. Details of skin preparation suggest that the entire type series came from Briceño e hijos, wellknown commercial collectors and taxidermists active at Mérida around the turn of the last century .

GEOGRAPHIC DISTRIBUTION: Referred specimens are from the foothills and crest of the Cordillera Oriental of Colombia, from the adjacent but disjunct Serranía de la Macarena, and from western and northern Venezuela. The known range of this species in Venezuela includes the foothills of the Serranía de Perija´, the lowlands of the western Maracaibo Basin, the Cordillera de Mérida, and the Cordillera de la Costa. Recorded elevations on specimen tags range from 54 to 2600 m above sea level.

DESCRIPTION: External —The pelage of Coendou pruinosus is morphologically sim­ ilar to that of C. vestitus but differs in coloration. Although the dorsal fur is predominantly blackish (Thomas, 1905) or dark brown, the hair tips are pale (grayish or silvery), producing a frosted effect that is more pronounced in some individuals (e.g., BMNH 10.12.3.5) than in others (e.g., BMNH 26.11.4.11). The fur is long (50–70 mm midorsally) and dense enough to conceal most of the underlying quills except on the head. All of the body quills (30–40 mm long middorsally) are bicolored (yellowish or ivory­white basally with the extreme tips dark brown), but some of the quills on the crown of the head and on the cheeks are tricolored (with white bases and tips separated by a broad dark middle band). Scattered throughout the dorsal pelage—except over the rump—are many long (to 80–100 mm) wirelike bristle­quills, the pale (usually ivorywhite or yellowish) tips of which are conspicuous against the dark background of the fur; most of the bristle­quills are actually tricolored (with pale bases and tips separated by a single dark middle band), but some are entirely pale. The ventral body pelage consists of soft frosted­brown fur from chin to anus. Longer, straighter, coarser guard hairs can be distinguished from finer, shorter, wavy wool hairs in the ventral pelage, but there are no conspicuously thickened spinous hairs rooted in obvious clusters.

The tail is short, averaging slightly more than half the combined length of the headand­body in specimens from montane habitats (e.g., the Alturas de Pamplona and Mérida series in table 2), but specimens from the Maracaibo lowlands (e.g., MHNLS 7692) and Caracas (BMNH 26.11.4.11) appear to have relatively and absolutely longer tails. Whereas the dorsal surface of the proximal half of the tail is covered by a mixture of quills and soft fur like that on the rump, paletipped bristles occur along the sides of the tail and converge posteriorly onto the caudal dorsum forming a conspicuous pale (yellowish or whitish) chevron. The prehensile tail tip is naked and calloused dorsally, but the rest of the tail is covered by blackish bristles; the bristles under the base of the tail are much stiffer and denser than those on the lateral and dorsal surfaces. The dorsal surface of the hands and feet are covered with coarse frosted­brownish hairs.

The cranial and postcranial vibrissae have the same morphology, coloration, and anatomical distribution as previously described for Coendou vestitus .

Skull —The frontal and nasal sinuses are uninflated in most specimens, resulting in a dorsal profile that is nearly flat from the nasal tips to the midparietal region; a single specimen (MHNLS 7692), however, has slightly inflated dorsal sinuses that produce a small but distinct swelling over the maxillary zygomatic roots. The rostrum is short and tapering in subadults and young adults, but lengthens in older animals, some of which develop shallow lateral excavations for the infraorbital muscle. The nasal bones are approximately parallel­sided in some specimens and taper slightly posteriorly in others, but always have rounded posterior margins that extend well behind the premaxillae. Viewed from above, the zygomatic arches converge anteriorly from the squamosal roots without a well­developed secondary widening at the orbits; some specimens (e.g., FMNH 140260), however, have more round­ ed (less angular) zygomatic outlines than others (e.g., MCZ 18738; fig. 8). The jugals are moderately deep (dorsoventrally expand­ ed), with some specimens (e.g., BMNH 10.12.3.5, USNM 172985) exhibiting a distinct postorbital swelling. The bony crests and scars associated with the origin of the temporalis muscle are strongly developed in some specimens, but a sagittal crest is not developed in any of the material examined.

The incisive foramina are moderately long and usually bordered posteriorly by the maxillae, but they do not penetrate deeply between those bones; in most specimens, the left and right foramina are completely separated by a bony septum and are not recessed in a common fossa. (A single specimen among those we examined, USNM 496172, is an exception: the foramina are contained within the premaxillae, and are incompletely separated and recessed in a common fossa.) The posterior diastema is marked by shallow and widely separated lateral sulci. The palatal bridge between the toothrows is smooth (e.g., AMNH 21350) or weakly keeled (USNM 172985), but lacks deep lateral gut­

TABLE 2 Measurements (mm) of Adult Specimens of Coendou pruinosus

ters (fig. 5B). The mesopterygoid fossa is shallow in most specimens (penetrating only between the third molars) and the bony roof of the fossa is perforated by tiny nutrient foramina or by small irregular holes that do not have the aspect of distinct sphenopalatine vacuities. The alisphenoid is completely ossified in all specimens examined, such that the sphenopterygoid canal is enclosed laterally and the buccinator­masticatory foramen is not confluent with the foramen ovale (fig. 6B). The auditory bullae are small (ca. 14– 15 mm) rounded capsules that are well separated from the paroccipital processes in most specimens, but three skulls (BMNH 26.11.4.11; FMNH 140261; MHNLS 7692) have unusually large (16–18 mm) bullae. The dorsal roof of the external auditory meatus has an indistinct bony ridge in most adult specimens, but two specimens (MHNLS 7692, USNM 496172) have distinct auditory ridges.

The mandible bears a small but distinct coronoid process in all specimens examined.

Dentition —The dentition of Coendou pruinosus is similar to that of C. vestitus , apparently without any distinctive features.

COMPARISONS: Coendou pruinosus and C. vestitus are similar in many points of comparison, yet each is morphologically distinctive. Externally, pruinosus differs from vestitus by its frosted (versus unicolored­dark) dorsal and ventral fur, tricolored (versus bicolored) head quills, pale­tipped (versus dark­tipped) bristle­quills, and chevron of pale­tipped caudal bristles (versus caudal chevron absent). Cranially, the two species are clearly distinguishable by palatal morphology (the bony palate between the toothrows is more distinctly ridged and grooved in vestitus than in pruinosus ), mesopterygoid perforation (distinct sphenopalatine vacuities are present in vestitus versus absent in pruinosus ), alisphenoid ossification (the sphenopterygoid canal is laterally open in vestitus versus closed in pruinosus ), and mandibular morphology (a distinct coronoid process is absent in vestitus but present in pruinosus ). In addition, other modal differences support the hypothesis that these are genetically differentiated taxa: (1) rostral morphology (the sides of the rostrum appear to be more deeply excavated for the origin of the infraorbital muscle in vestitus than in like­aged pruinosus ); (2) depth of the jugal (more dorsoventrally expanded below the orbit in pruinosus than in vestitus ); (3) morphology of the incisive foramina (short, incompletely separat­ ed, and contained entirely by the premaxillae in most vestitus versus longer, completely separated, and bordered by the maxillae in most pruinosus ); and (4) depth of the mesopterygoid fossa (penetrating to or between the second molars in vestitus versus shallow­ er in most pruinosus ). Although only small samples are currently available for taxonomic comparisons, these differences permit unambiguous identifications and seem more than sufficient to recognize C. vestitus and C. pruinosus as valid species.

VARIATION: Consistent with its larger ecogeographic range, Coendou pruinosus is more morphologically variable than C. vestitus , but all of the referred material shares a common aspect and we provisionally regard it as representing conspecific populations. Nevertheless, a few specimens from geographically peripheral localities are notably atypical. In particular, AMNH 136312 (from the foothills of the Cordillera Oriental in Departamento Meta, Colombia) has unusually sparse fur, a deep mesopterygoid fossa (extending between the second molars), and small toothrows (MTR, 13.3 mm); its bullae are relatively longer (approaching the base of the paroccipital process on each side) and more laterally compressed than those seen in topotypical material. Likewise, MHNLS 7692 (from the foothills of the Serranía de Perija´) has uniquely swollen frontal sinuses, dorsal bristles tipped with pale orange (instead of white or pale yellow), and very large bullae. Finally, the single specimen examined from the Cordillera de la Costa (BMNH 26.11.4.11, a subadult) has unusually short incisive foramina, small teeth, and large bullae. The possibility that such outliers represent distinct taxa merits testing when more material becomes available from these areas.

REMARKS: A specimen collected ca. 75 km SW of the type locality was karyotyped by Concepción and Molinari (1991), who report­ ed a diploid number of 42 and a fundamental number of 76. Their morphological description of the karyotyped animal is consistent with that given above for Coendou pruinosus , with only minor differences. The reported external dimensions and weight of this specimen (CVULA I­3030, an adult male) are the only such data obtained to date from positively identified fresh material near the type locality: 300 mm (HBL) × 220 mm (Tail) × 55 mm (HF, c.u.) × 22 (Ear) = 1010 g.

Specimens currently labeled as ’’ Sphiggurus vestitus ’’ in Venezuelan museums are presumably referable to Coendou pruinosus as herein recognized, but the following material should be examined for diagnostic attributes to confirm this identification: EBRG 126 (Aragua, Rancho Grande), EBRG 4350 (Mérida, 2 km E Jajı´), EBRG 10281 (Miranda, Parque Nacional El Avila), EBRG 20243 (Aragua, Colonia Tovar), MBUCV 1472 (Distrito Federal, Carayaca), MBUCV 4155 (Miranda, Estación Experimental de Río Negro), MHNLS 58 (Miranda, Turgua), MHNLS 3879 (Distrito Federal, Caracas), MHNLS 8480 (Zulia, Hacienda La Ceiba).

NATURAL HISTORY: All known specimens of Coendou pruinosus have been collected in regions where the original (non­anthropogenic) vegetation is (or was) humid forest. At elevations below 1000 m, the species inhabits lowland rainforest, but at higher elevations the typical habitat is probably cloud forest (Lower Montane or Upper Montane Rainforest; Grubb, 1977). To the best of our knowledge, no specimens have been taken in unforested (e.g., savanna or páramo) landscapes.

Published natural history information can be associated with only three positively identifiable records of Coendou pruinosus . Handley (1976: 55) reported that one individual ( USNM 496172 , an adult male) was ‘‘found in a tree in an upland area in mature evergreen forest’’ near El Rosario (54 m elevation; Estado Zulia, Venezuela), where the local vegetation was further characterized as ‘‘[m]ature evergreen forest 18–30 m high, with many palms and vines’’ (op. cit.: 69). Concepción and Molinari (1991: 238) subsequently reported another specimen (CVU­ LA 1–3030, also an adult male) that was captured ‘‘in an area dominated by cloud forest’’ at an elevation of 1500 m near the town of Zea (Estado Mérida, Venezuela) .

On the night of 6 July 1986, Voss shot another adult male specimen (MHNLS 7692) that was perched about 20 m above the ground on the trunk of a large buttressed tree festooned with lianas and epiphytes near Misión Tukuko (ca. 300 m elevation; Estado Zulia, Venezuela). The tree was part of the original rainforest canopy at this site, but most of the surrounding undergrowth had been cleared for cacao cultivation (for a detailed description of local habitats, see Voss, 1991: 68–70). The freshly dissected stomach was full of brownish paste, possibly consisting of chewed bark; no insect parts, seeds, or other identifiable food fragments were observed.

SPECIMENS EXAMINED: Colombia — Meta, Villavicencio (AMNH 136312), Pico Rengifo (FMNH 87896); Norte de Santander, Alturas de Pamplona (FMNH 140260, 140261). Venezuela — Distrito Federal, Caracas (BMNH 26.11.4.11); Mérida, Mérida (AMNH 21350, BMNH 5.7.5.10, 10.12.3.5), Montañas de la Pedregosa (BMNH 5.7.5.9), ‘‘Montaña de la Sierra’’ (MCZ 18738, ZMB 33377), Montañas de Tabay (BMNH 5.7.5.12), ‘‘Montaña del Valle’’ (BMNH 5.7.5.8, 5.7.5.11); Zulia, El Rosario (USNM 496172), Misión Tukuko (MHNLS 7692). ’’ South America ’’ (USNM 172985).

Coendou ichillus , new species

Figures 9–12

TYPE MATERIAL: The holotype, AMNH 126171 , consists of the skin, skull, and man­

dibles of a young adult of unknown sex collected by the von Baumann­Roosevelt Expedition in July 1936 on the Río Pastaza, Ecuador . 3 The stuffed skin (fig. 9) appears to be slightly faded, but is in otherwise perfect condition with no missing elements. The skull (fig. 10) lacks part of both nasal bones together with most of the right premaxilla, but is otherwise complete. Two paratypes are from unknown localities on the Río Conambo ( EPN 806 , an adult female) and the Río Yana Rumi ( FMNH 43289 , an adult male), both in Provincia Pastaza, Ecuador .

GEOGRAPHIC DISTRIBUTION: All unambiguous records of Coendou ichillus are from the Amazonian lowlands of eastern Ecuador, but a referred juvenile specimen purchased near Iquitos (see Variation, below) suggests that the species is more widely distributed.

ETYMOLOGY: From ichilla, meaning ‘‘small’’ (Orr, 1978) in the dialect of the lowland Quichua, within whose tribal territory the new species occurs.

DIAGNOSIS: A member of the Coendou vestitus group distinguished from other species by its long tail, lack of visible fur in the adult pelage, more extensively black­tipped quills, tricolored (pale­tipped) bristle­quills, spiny ventral pelage, and a unique combination of cranial traits.

DESCRIPTION: External —No soft fur is apparent in the dorsal pelage except by close examination because the blackish wool hairs are sparse and hidden among the quills and bristles; a few dorsal wool hairs plucked from two specimens were about 40 mm in length. All of the quills (30–40 mm long middorsally) are bicolored (yellowish basally with the terminal ⅓ to ½ dark­brown or

3 The original specimen label gives the locality as ‘‘Rio Pastaza’’ only, but the entire von Baumann­Roosevelt collection (including 10 other mammals and 25 birds variously labeled ‘‘Rio Tigre’’, ‘‘Rio Bobonaza’’, Rio Blanco’’, ‘‘Rio Pastaza’’, and ‘‘Rio Napo’’) was known to have been obtained in Ecuador, so the lower (Peruvian) course of this river can be ruled out. Unfortunately, the exact route traveled by the von Baumann­ Roosevelt Expedition is unknown, and no archival record of the purpose or staffing of this mysterious outfit appears to exist. Filed correspondence with its director, Cyril von Baumann, consists only of an AMNH accessions receipt dated 23 January 1937, together with a curt acknowledgment from von Baumann dated 1 February.

×0.4.

blackish), except on the head, where some quills are tricolored (with ivory­white bases and tips separated by a dark middle band). Densely scattered among the quills are many long (to ca. 80 mm) thin bristle­quills with yellowish bases and tips separated by a broad dark­brown or blackish middle band; the pale tips of the bristle­quills produce a character­ istically streaked effect over the whole dorsum with the exception of the rump (which is covered only with short bicolored quills and a few wool hairs). The ventral body pelage consists of very coarse bicolored or tricolored hairs (ca. 0.30–0.40 mm in diameter and 15 mm long) that are usually rooted in triplets but occasionally in groups of two or

TABLE 3 Measurements (mm) of All Known Adult Specimens of Coendou ichillus

four; a few short wool hairs are almost invisibly scattered among this harsh covering.

The tail is moderately long, averaging rather more than ¾ of head­and­body length on the two skins from which approximate measurements could be obtained (table 3); in life, the extended tail of one individual (only partly visible in fig. 12) seemed to be almost as long as the head and body, but no accurate measurement could be taken from this unrestrained animal (see Natural History, below). The dorsal part of the base of the tail is densely covered with short bicolored quills like those of the rump, but tricolored bristles extend along the lateral caudal surfaces and converge dorsally to form an indistinct whitish or yellowish chevron near the middle of the tail. The prehensile tail­tip is calloused and naked dorsally, but the rest of the tail is densely covered by blackish bristles; the caudal bristles are conspicuously stiffer and denser under the base of the tail than elsewhere. The hands and feet are covered dorsally with coarse blackish hairs.

The cranial and postcranial vibrissae of this species have the same morphology, coloration, and distribution as previously described for Coendou vestitus .

Skull —The frontal and nasal sinuses are uninflated, resulting in a flat dorsal profile from the nasal tips to the midparietal region. In dorsal view, the rostrum is short and moderately broad, lacking obvious lateral emarginations for the origin of the infraorbital muscle. The nasal bones are damaged in two of the three specimens at hand, but appear to taper gently from front to back; the posterior nasal margins are rounded and extend behind the premaxillae (much more so in FMNH 43289 than in AMNH 126171). Viewed from above, the zygomatic arches are rounded (AMNH 126171) or biconcave (EPN 807, FMNH 43289) because they are anteriorly deflected to accommodate relatively larger orbits than those of either Coendou vestitus or typical C. pruinosus . The jugals have either a small postorbital expansion (AMNH 126171, EPN 807) or taper more­or­less evenly from front to back (FMNH 43289). The dorsolateral contours of the braincase show only slight to moderate sculpting for the origin of the temporalis muscle; the right and left temporalis scars are widely separated in all three specimens examined.

The small incisive foramina are incompletely separated and recessed in a common fossa that is contained entirely by the premaxillae (EPN 807) or bordered narrowly by the maxillae behind. The posterior diastema is marked by shallow and widely separated lateral sulci. The palatal bridge between the toothrows does not have a distinct median keel or deep lateral gutters in any of the specimens examined. The mesopterygoid fossa extends anteriorly just beyond the point of contact between M2 and M3, and the bony roof of the fossa (in AMNH 126171 and EPN 807) is not perforated by distinct sphenopalatine vacuities. The alisphenoid is completely ossified such that the sphenopterygoid canal is enclosed laterally and the buccinator­masticatory and oval foramina are separate. The auditory bullae are large (ca. 16–17 mm) inflated capsules that contact the base of the paroccipital process on each side. The dorsal roof of the external auditory meatus lacks a distinct bony keel in both specimens at hand (AMNH 126171, FMNH 43289).

The mandible is provided with a small but well­developed coronoid process.

Dentition —The dentition is qualitatively similar to that of Coendou vestitus and C. pruinosus , but measurements suggest that the incisors are relatively broader than in those species, and they appear to be more deeply pigmented as well.

COMPARISONS: No other species of the Coendou vestitus group lacks a visible coat of long fur, and this trait together with its relatively long tail and spiny ventral pelage make C. ichillus externally unmistakable. Additionally, the pigmented tips of the defensive quills are much longer in ichillus than in either vestitus or pruinosus ; as a result, when the long fur of the latter two species is shed or parted, the exposed quills and bristles produce the effect of a pale (yellowish or whitish) animal streaked and stippled with dark brown, whereas the permanently exposed quills and bristles of ichillus produce the effect of a blackish animal streaked with white or yellow.

Cranially, Coendou ichillus is distinguished from C. vestitus and from typical examples of C. pruinosus by its proportionately smaller and less laterally excavated rostrum, more rounded (or biconcave) zygomatic arches, and proportionately larger bullae. From vestitus , the new species additionally differs by its less strongly muscle­scarred braincase, less strongly keeled and grooved palatal bridge, unperforated mesopterygoid fossa, and distinct mandibular coronoid process. From pruinosus , the new species additionally differs by its smaller incisive foramina and more anterior mesopterygoid penetration.

External and cranial comparisons with the second new species are provided in the following account.

VARIATION: Cranial differences among the three available adult specimens of Coendou ichillus do not exceed the range of osteological variation routinely observed within local populations of other Neotropical porcupines. However, the skin of the holotype appears to be faded by comparison with the more vividly colored paratypes. The latter closely resemble living examples (fig. 12), whose dark pelage markings are distinctly blackish. By contrast, the corresponding pigmentation on AMNH 126171 is brownish (near Smithe’s [1975] Sepia or Raw Umber), a chromatic difference that might have resulted from inadequate specimen storage (e.g., exposure to light or bleaching agents) at some point in the past.

An immature specimen (FMNH 112565) purchased by Pekka Soini in 1971 near Iquitos is mounted for display with the skull inside and has painted seeds for eyes; obviously intended for the tourist trade, it is unaccompanied by records of sex, measurements, or habitat. The dorsal body pelage consists of bicolored quills, tricolored bristlequills, and long reddish fur; the ventral pelage consists mostly of reddish fur, but a few clusters of soft spines are emerging along the midline. Measurements made with a flexible rule suggest that the tail in life was more than three­quarters of the combined length of head and body; the estimated length of the dried hind foot is ca. 48 mm.

Long reddish juvenile fur appears to be a taxonomically widespread trait among Neotropical porcupines, occurring even in those species that lack visible fur as adults (Roberts et al., 1985; Handley and Pine, 1992). We identify FMNH 112565 as Coendou ichillus because its long tail, boldly black­tipped quills, tricolored bristle­quills, and emerging ventral spines suggest a similar external phenotype at maturity. Although this identification is biogeographically plausible (other eastern Ecuadorean taxa have ranges that extend southeastward into Peru, e.g., Saguinus nigricollis graellsi ; Hershkovitz, 1977: fig. X.21), the exact provenance of FMNH 112565 is uncertain because tourist items sold near Iquitos might have originated far from the city.

NATURAL HISTORY: Although no useful ecological association can be inferred from the type locality, ‘‘Río Pastaza’’, a river that traverses a considerable range of habitats in its descent from the Andes to the Amazon, both paratypes are from densely rainforested catchments below 500 m elevation. The orig­ inal skin tag attached to FMNH 43289 includes the notation ‘‘Col[ectado]: con cerbatana y beneno’’ (collected with blowgun and poisoned dart), suggesting that the animal was taken from a tree by a native hunter, probably belonging to one of the lowland Quichua groups described by Whitten (1976). No other natural history information is available from any of the specimens at hand.

Fortunately, field observations of Coendou ichillus are available from at least one definite locality: La Selva Jungle Lodge, an ecotourist facility and biological station at ca. 300 m elevation on the left (north) bank of the Río Napo in Provincia Sucumbíos, Ecuador. Situated between the oxbow lakes of Garza Cocha and Mandi Cocha, the lodge and its surrounding trail system occupy the typical ridge­and­swale landscape created by meandering white­water rivers, with tall forest on the high ground and swamps in the valley bottoms. Balslev et al. (1987) provid­ ed a detailed description of the local vegetation based on their study of flooded and unflooded forest at nearby Añangu (on the opposite bank of the Napo). Several years of weather records from La Selva suggest that this region receives between 3500 and 4000 mm of annual rainfall (DeVries et al., 1999).

An adult female porcupine, unambiguously identifiable as Coendou ichillus , was briefly observed at La Selva (by J. E. Cadle, P. J. DeVries, L. H. Emmons, and R. S. Voss) on the night of 9 July 1996 as it ate ripe bananas suspended by a cord from the rafters of a building surrounded by gardens and secondary vegetation (fig. 12). Several days later, another adult C. ichillus was observed at night (by J. E. Cadle and L. H. Emmons) in adjacent primary floodplain forest, where it was perched on a liana about 8 m above the ground. At least two individuals were said by lodge employees to inhabit holes in hollow palm trunks that were used as upright supports for the kitchen and other buildings at La Selva.

SPECIMENS EXAMINED: Ecuador — Pastaza, Río Conambo ( EPN 807 ) , Río Yana Rumi ( FMNH 43289 ) ; Río Pastaza ( AMNH 126171 [holotype]) . Peru — Loreto, Iquitos region ( FMNH 112565 ) .

Coendou roosmalenorum , new species

Figures 13 , 14

TYPE MATERIAL: The holotype, INPA 2586 (original number CCM 58 ), consists of the well­preserved skin, skull, and mandibles of an adult female collected by M.G.M. and T. van Roosmalen on 23 November 1996 at the caboclo settlement of Novo Jerusalem near the left bank of the middle Rio Madeira in the Brazilian state of Amazonas . One paratype ( INPA 2587 ) is from the nearby village of Santa Maria on the same side of the Madeira, but the other ( INPA 677 ) is from 49 km E Porto Velho on the opposite bank in the Brazilian state of Rondônia .

GEOGRAPHIC DISTRIBUTION: Known from both banks of the middle Rio Madeira in Brazil between 5 and 9° S latitude .

ETYMOLOGY: For Marc van Roosmalen and his son Tomas, whose collections from the middle Madeira included this distinctive porcupine together with other previously undescribed mammalian taxa (Roosmalen et al., 1998, 2000).

DIAGNOSIS: A member of the Coendou vestitus group distinguished from other member species by its small size, long tail, long adult fur, minutely black­tipped quills, nonspinous ventral fur, and unique combination of craniodental traits.

DESCRIPTION: External —The dorsal fur of soft wool hairs is dull in appearance and apparently variable in coloration, pale grayishbrown in one specimen (INPA 2586) but dark brown in the other two (INPA 677, 2587); in the specimens with brownish dorsal fur, the hair tips are pale (grayish or silvery) but these do not produce a distinctly frosted mass effect. The dorsal fur is long (50–70 mm) and dense enough over the back and rump to partly (INPA 2586, 2587) or completely (INPA 677) conceal the underlying quills. All of the quills (ranging in length from about 25 to 35 mm middorsally) are bicolored (yellowish basally with the extreme tips dark brown) over the entire dorsum, including the head. Scattered abundantly throughout most of the dorsal pelage (except the rump) are long (40–70 mm) wirelike bristle­quills; almost all of these are tricolored—with pale (yellowish or ivorywhite) bases and tips separated by a single

TABLE 4 Measurements (mm) of All Known Specimens of Coendou roosmalenorum

dark­brown middle band of variable width— but a few bristles are bicolored (with pale bases and dark tips). The ventral surface of the body is densely covered with a mixture of fine, soft, brownish wool and coarser, banded (tricolored or bicolored) hairs from chin to anus; the banded hairs (0.20–0.25 mm in diameter and 15–20 mm long) are rooted in clusters, usually triplets but occasionally groups of two or four.

The long tail is almost 90% of head­andbody length in both of the specimens from which measurement data are available (table 4). The basal third of the tail is covered dorsally with bicolored quills and woolly fur, and the prehensile tail­tip is bare and calloused dorsally, but the rest of the tail (above and below) is uniformly covered with blackish bristles; the caudal bristles under the base of the tail are stiffer and denser than those occurring elsewhere. The dorsal surfaces of the hands and feet are densely covered with coarse dark­brown or blackish hairs.

The cranial and postcranial vibrissae have essentially the same morphology, coloration, and anatomical distribution as previously described for other vestitus ­group porcupines.

Skull —The frontal and nasal sinuses are slightly inflated in the younger left­bank specimens (INPA 2586, 2587), producing a slightly swollen dorsal profile above the orbits; the sinuses of the older right­bank specimen (INPA 677) are uninflated, however, resulting in a flat dorsal profile from the nasal tips to the midparietal region. The rostrum is short and tapering in our younger examples but moderately broad in INPA 677; however, there are no well­developed lateral emarginations for the origin of the infraorbital muscle in any specimen. The nasal bones taper gently from front to back, with rounded posterior margins that extend well behind the premaxillae. Viewed from above, the zygomatic arches converge anteriorly from the squamosal roots without a conspicuous widening at the level of the orbits. The jugals are moderately deep with distinct postorbital processes in all examined material. The dorsolateral contours of the braincase are only slightly (INPA 2587) to moderately (INPA 2586 and 677) sculpted by the origin of the temporalis muscles. The left and right temporalis scars are widely separated and are not joined middorsally to form a sagittal crest in any specimen.

The incisive foramina are short and almost completely contained in the premaxillae (INPA 2586), or longer and penetrating between the maxillae posteriorly (INPA 2587, 677); the left and right foramina are completely separated by a bony septum in INPA 2586, but the septum is incomplete and both foramina are recessed in a common fossa in the other two specimens. The posterior diastema is marked by shallow and widely separated lateral sulci. Although the palatal bridge between the toothrows has a weakly developed central keel and shallow lateral gutters anterior to M1, the posterior palate is more­or­less smooth. The mesopterygoid fossa extends slightly anterior to the point of contact between M2 and M 3 in the holotype, but not in either paratype. Small sphenopalatine vacuities (ca. 1 mm in diameter) per­ forate the bony roof of the mesopterygoid fossa in INPA 677, but not in INPA 2586 (the mesopterygoid region of INPA 2587 is too damaged to score confidently for this trait). The alisphenoid is completely ossified, such that the sphenopterygoid canal is enclosed laterally and the buccinator­masticatory foramen and the foramen ovale are separate. The auditory bullae are large (ca. 17 mm) inflated capsules that contact the base of the paroccipital process on each side. The dorsal roof of the external auditory meatus has a weakly developed bony ridge in two specimens (INPA 677 and 2587) but not in INPA 2586.

The coronoid process of the mandible is well­developed in all examined specimens.

Dentition —The dentition is qualitatively similar to that of the remaining species of the vestitus group, but the toothrows of INPA 2586 and INPA 677 are remarkably small (table 4). The upper incisors are strongly procumbent and deeply pigmented (orange).

COMPARISONS: Coendou roosmalenorum can be distinguished unambiguously from other species of the vestitus group by a unique combination of characters, the most salient of which are tabulated for easy reference (table 5). Externally, roosmalenorum resembles vestitus and pruinosus by its long, dense dorsal fur and nonspinous ventral pelage, but it differs from both of those species in details of fur coloration (grayish or brownish versus blackish), in body size (much smaller, as indicated by hindfoot measurements), and by its conspicuously longer tail. Other external characters provide different patterns of taxonomic contrasts. Like vestitus , roosmalenorum has only bicolored cranial quills, whereas at least some cranial quills are tricolored in all examined specimens of pruinosus . Like pruinosus , however, roosmalenorum has tricolored bristle­quills, whereas the bristle­quills of vestitus are bicolored. In craniodental traits, roosmalenorum differs from vestitus in palatal sculpturing, alisphenoid ossification, bullar size, mandibular morphology, and in many additional (but subtler) details. From pruinosus , roosmalenorum differs craniodentally by its relatively much larger bullae, but other osteological contrasts between these taxa are harder to assess due to the wide range of var­ iation among referred specimens. For example, the contrast in rostral morphology between some exemplar crania of pruinosus (e.g., MCZ 18738; fig. 8) and roosmalenorum (e.g., INPA 2586; fig. 14) is striking, but other specimens that we could have chosen to represent each species (e.g., FMNH 140260 [ pruinosus ] and INPA 677 [ roosmalenorum ]) are much more similar in this character. Average (or modal) character differences between roosmalenorum and pruinosus , however, include dental size ( roosmalenorum has smaller molars), mesopterygoid penetration between the toothrows (deeper in roosmalenorum ), mesopterygoid fenestration (sphenopalatine vacuities are better developed in roosmalenorum ), and nasal/frontal sinus inflation (perhaps more frequent in roosmalenorum ).

Although Coendou roosmalenorum and C. ichillus are both long­tailed species, they differ markedly in external appearance, most notably in dorsal fur length (long versus short, respectively), density (dense versus sparse), and color (gray or brown versus blackish); in addition, whereas the quills of roosmalenorum are only dark at the extreme tips, those of ichillus are much more extensively pigmented. Other trenchant external differences include size ( roosmalenorum is smaller, as evidenced by hindfoot measurements), and ventral pelage composition (coarse banded hairs in ichillus , woollier in roosmalenorum ). The sum of such contrasts is sufficiently striking that it is unlikely that these species could be confused in the field by competent observers. By contrast, cranial differences between roosmalenorum and ichillus are harder to identify given the small samples at hand. Although it is possible that the morphology of the nasal/frontal sinuses (perhaps more frequently inflated in roosmalenorum ), zygomatic arches (perhaps more rounded in ichillus ), and the mesopterygoid roof (perhaps more frequently fenestrated in roosmalenorum ) might have some diagnostic value alone or in combination, larger samples are clearly needed to assess such modal differences.

Body weight data suggest that Coendou roosmalenorum is one of the smallest living erethizontids, but the adult holotype (INPA 2586, 600 g) may have been emaciated (see

TABLE 5 Morphological Comparisons Among Four Species of the Coendou vestitus Groupa

below), and the other weighed specimen (INPA 2587, 800 g) is a subadult. By comparison, 42 postjuvenile 4 specimens of C. melanurus weighed by Richard­Hansen et al. (1999) ranged from 1500 to 2600 g, and 70 specimens of C. prehensilis weighed by the same authors ranged from 1800 to 5800 g.

VARIATION: With only three specimens in hand, the possible significance of observed character variation in Coendou roosmalenorum is hard to evaluate. Although certain differences observed in our material are plausibly attributable to ontogeny, others are not. An example of the former is the rostrum of INPA 677 (an old adult), which is relatively and absolutely larger than the rostrums of INPA 2587 (a subadult) and INPA 2586 (a young adult). An example of the latter is the grayish dorsal fur of INPA 2586 versus the brownish fur of the other two skins.

Although we examined specimens from both banks of the Rio Madeira, a major Amazonian tributary and one of the largest rivers in the world, the similarities uniting our material as a taxon diagnosable from other forms of Coendou are more persuasive than the few differences that segregate our leftbank examples (INPA 2586, 2587) from our right­bank singleton (INPA 677). However, the more inflated sinuses of the former specimens are perhaps noteworthy in this context, as is the extremely small toothrow of the latter. Future studies based on larger samples from both populations will doubtless contribute to a more informed judgement about their taxonomic status.

NATURAL HISTORY: According to information kindly summarized for us by Marc van Roosmalen, the holotype was captured by caboclos at Novo Jerusalem when it emerged from a felled tree. Kept alive as a pet, the animal was released every evening to roam freely in the surrounding terra firme forest, returning at dawn to sleep throughout the day in a box underneath its owners’ house. This individual subsequently lived for several months in captivity at Manaus, where it maintained its nocturnal habits (sleeping in

4 Richard­Hansen et al. (1999) judged their weighed specimens to be adults, but those authors did not employ dental criteria to assess maturity. Most subadult porcupines are externally indistinguishable from adults.

a tree hole by day), and ate a variety of seeds and fruit. It died of unknown causes while seeming perfectly healthy.

The paratype from Santa Maria was shot at night by a caboclo boy who mistook its eyeshine for that of a paca ( Cuniculus paca ) as it was walking on the ground no more than 100 m from the shore of Lago Matupiri, a blackwater lake. The local vegetation was tall ‘‘seringal’’ forest growing on terra firme with abundant rubber trees ( Hevea brasiliensis ), Brazil nuts ( Bertholletia excelsa ), ingas ( Inga spp. ), and other trees known locally as orelha de macaco ( Enterolobium schomburgkii ), bacuri ( Rheedia macrophylla ), and taperebá ( Spondias mombin ).

The paratype from 49 km E Porto Velho was taken in the course of faunal rescue efforts at the Samuel hydrolectric dam site, but the ecological circumstances of its capture are unknown.

REMARKS: Three specimens (two males and one female) collected at the Samuel hydroelectric dam site (49 km E of Porto Velho on BR 364) were identified by Naiff et al. (1996) as the ‘‘Black dwarf porcupine’’ of Emmons (1990: 199), a taxon that is technically known as Coendou nycthemera Olfers (see Voss and Angermann [1997], who explain that C. koopmani Handley and Pine is a junior synonym). One of those specimens (the female, INPA 677) is a paratype of C. roosmalenorum , but the whereabouts of the two male specimens is unknown. It is difficult to understand how INPA 677 could possibly have been mistaken for Emmons’ black dwarf porcupine, which was clearly described by her as having entirely spiny blackish upperparts. One possible explanation is that the two missing specimens from Naiff’s series were, in fact, C. nycthemera (which is known to occur on the right bank of the lower Madeira near Borba), and that INPA 677 was mistaken for a conspecific long­furred juvenile. Whether or not this conjecture is correct, future collectors should be alert to the possibility that two small species of Coendou may be sympatrically or parapatrically distributed along the right (east) bank of the Madeira.

SPECIMENS EXAMINED: Brazil — Amazonas, Novo Jerusalem (INPA 2586), Santa Maria

(INPA 2587); Rondônia, 49 km E Porto Velho (INPA 677).

Figures

Fig. 5. Ventral cranial views of Coendou vestitus (A, MNHN 1929–632) and C. pruinosus (B, MCZ 18738) showing species differences in palatal morphology. In Coendou vestitus, the bony palate between the toothrows is marked by a high median keel that is flanked by deep lateral grooves or gutters (lg); in addition, the mesopterygoid fossa (mpf) extends anteriorly between the second molars, and the roof of the fossa is perforated by large sphenopalatine vacuities (spv). In C. pruinosus, the palate is sometimes weakly keeled but never has deep lateral gutters; also, the mesopterygoid fossa extends anteriorly only between the third molars, and the roof of the fossa is not perforated by distinct sphenopalatine vacuities.

Fig. 6. Ventrolateral cranial views of Coendou vestitus (A, AMNH 71360) and C. pruinosus (B, MCZ 18738) showing species differences in alisphenoid morphology. In Coendou vestitus, the alisphenoid is incompletely ossified, resulting in an open sphenopterygoid canal and a buccinator­masticatory foramen (bmf) that is confluent with the foramen ovale (fo). By contrast, the alisphenoid is fully ossified in C. pruinosus, whose sphenopterygoid canal (arrow) is laterally enclosed and whose buccinator­masticatory and oval foramina are separate.

Fig. 7. Dorsal view of the skin of Coendou pruinosus (BMNH 10.12.3.5). Approximately ×0.4.

Fig. 8. Dorsal, ventral, and lateral cranial views of Coendou pruinosus (MCZ 18738). All views approximately ×1.5.

Fig. 9. Dorsal view of the skin of Coendou ichillus (AMNH 126171, holotype). Approximately

Fig. 10. Dorsal, ventral, and lateral cranial views of Coendou ichillus (AMNH 126171, holotype). All views approximately ×1.5.

Fig. 11. Dorsal, ventral, and lateral cranial views of Coendou ichillus (FMNH 43289, paratype). All views approximately ×1.5.

Fig. 12. An adult female Coendou ichillus eating bananas suspended from the rafters of a building at La Selva Jungle Lodge, Provincia Sucumbíos, Ecuador, on 9 July 1996 (photo courtesy of P. J. DeVries).

Fig. 13. Holotype of Coendou roosmalenorum (INPA 2586) in life. Photos courtesy of M.G.M. van Roosmalen.

Fig. 14. Dorsal, ventral and cranial views of Coendou roosmalenorum (INPA 2586 [original number CCM 58], holotype). All views approximately ×1.5.