A Review Of The Spiny Mouse Genus Scolomys (Rodentia, Muridae, Sigmodontinae) With The Description Of A New Species From The Western Amazon Of Brazil

19 Pages·1995·9.2 MB·

by  J L Patton

PROCEEDINGSOFTHE BIOLOGICALSOCIETYOFWASHINGTON
108(2):319-337. 1995.
A review of the spiny mouse genus Scolomys
(Rodentia: Muridae: Sigmodontinae) with the
description of a new species from the
western Amazon of Brazil
James L. Patton and Maria Nazareth F. da Silva
(JLP, MNFS) Museum ofVertebrate Zoology, University ofCalifornia,
Berkeley, California 94720 U.S.A.;
(MNFS) Departmento de Ecologia, Instituto Nacional de Pesquisas da Amazonia,
Manaus, AM, Brazil
Abstract.—Includedwithinacollectionofmammalsassembledduringayear-
long vertebrate survey ofthe Rio Jurua in the western Amazon Basin ofBrazil
is a series of specimens of a new spiny mouse of the genus Scolomys. This
genus is one ofthe more highly-localized and poorly-known murid rodents of
the neotropical forests. Prior to the collection reported here, there were two
recognized species known from a total of 15 specimens. One ofthese, S. me-
lanops Anthony, 1924, is known only from three closely spaced localities in
easternEcuador; the second, S. ucayalensisPacheco, 1991, isknownfrom only
one locality in north-central Peru. We provide areviseddiagnosis anddescrip-
tion ofthe genus while describing the third species, suggest phylogenetic affin-
ities ofthe genus within the tribe Oryzomyini, and summarize aspects ofthe
ecology and life history ofthe new species.
Resumo.—Uvci novo catito de espinho (genero Scolomys) foi coletado du-
rante um levantamento da fauna de vertebrados realizado no rio Jurua, no
oeste da Amazonia brasileira. Este genero de roedores murideos neotropicais
foipoucoestudadoepossuiumadistribuigaogeograficamuitorestrita. Somente
duasespecieseramateentaoconhecidas: umadolestedoEquador{S. melanops
Anthony, 1924; 13 especimesprovenientesdetreslocalidades)e outradonorte
do Peru {S. ucayalensis Pacheco, 1991; dois especimes provenientes de uma
localidade). Nesteestudonosdescrevemosumaterceiraespecieeapresentamos
umarevisaoaumentadadadiagnoseedescrigaodogenero. Tambem sugerimos
afinidades filogeneticas dentro da tribo Oryzomyini, alem de sumarizarmos
pela primeira vez aspectos da ecologia e historia natural desses animals.
The genus Scolomys contains small-bod- from three nearby localities in east-central
ied and strongly spinose mice of the tribe Ecuador. A second species, S. ucayalensis,
Oryzomyini Vorontsov, 1959 (sensu Voss was recently described by Pacheco (1991)
& Carleton 1993) of the South American based on two specimens from a single lo-
Sigmodontinae (Muridae) rodents. Each of cality in north-central Peru,
the two known species has a very localized We have obtained a series of 23 speci-
distribution in the forests ofwestern Ama- mens from four localities along the Rio Ju-
zonia. The genus was described in 1924 by rua in the lowland Amazonian forest of
H. E. Anthony and the type species, S. me- westernBrazil(statesofAmazonasandAcre)
lanops, is known from a total 13 specimens thatrepresentsathirdspeciesofthispoorly-
320 PROCEEDINGSOFTHE BIOLOGICALSOCIETY OFWASHINGTON
knowngenus. Basedonthesenewmaterials cusps that wear quickly with age; procin-
and an examination of most other speci- gulum of Ml undivided by anteromedial
mens, we provide an expanded diagnosis flexus; labial flexi deeply penetrating in all
and description of the genus and describe molars; lingual flexi reduced in size in Ml
thenewspecieshere. WealsocompareSco- andM2andobsoleteinM3; upperandlow-
lomys to the sympatric and superficially er molars with well-developed meso-
similaroryzomyinegenusNeacomysaswell loph(id)s; stomach unilocular and hemi-
as to other oryzomyine genera, provide re- glandular; male phallus cylindrical with in-
marks on phyletic relationships based on complete crater rim, terminally exposed
morphological characters and comparative urethral flaps, lateral mounds ofdistal bac-
DNA sequences, and summarize what few ulum hidden by tissue ofcraterrim, and an
facts are available on life history and ecol- epidermis with small and widely-spaced
ogy. spines.
Description.—Bodypelageshortandclose,
Scolomys AnXhony, 1924
with texture markedly spinose both above
Type species.—Scolomys melanops An- and below; color ranges from grizzled pale
thony (1924:2). reddish-black to nearly totally black dor-
Emended diagnosis.—Members of the sally and gray ventrally; dorsal hairs oftwo
tribe Oryzomyini (sensu Voss & Carleton types: (1) long (averaging 12 mm), stout,
1993) of the murid rodent subfamily Sig- flat, and broad (averaging 0.6 mm) spines
modontinae(sensuCarleton&Musser 1984) with a medial trough onboth surfaces, Avith
with 3 pairs ofmammae (1 thoracic, 1 ab- theterminal V3to V4increasinglydarktothe
dominal, and 1 inguinal [followingposition tipandproximalportionclear; and(2)long,
designationsgivenbyVoss&Carleton 1993; thinhairs oflengthequalto spinesandwith
Anthony (1924) recorded mammae as 1 tipsreddishorblackish;ventralhairsofboth
pectoral, 2 inguinal]). Pelage comprised of typesuniformlygrayfrom basetotip. Mys-
short, stiffspines on both dorsum and ven- tacial, superciliary, genal I, submental, in-
ter with equal-length normal hairs inter- terramal, and carpal vibrissae present. Pin-
spersedthroughout,givinggeneralspinyap- nae small, appearing somewhat thickened
pearance over entire body. Skull with short and thus stiff", and, while appearing naked
and blunt rostrum flanked by shallow zy- from a distance, are clothed externally and
gomatic notches; supraorbital margins internally with short reddish-brown hairs.
rounded, forming a moderately-developed Manus with five large, fleshy plantar pads
shelfoverhangingposteriorhalfoforbit,and (two carpal andthree interdigital); toespale
extending onto braincase as ridges; brain- in color; digit I reduced but with a small
case rather globular in shape; interparietal nail, digits II through V long and well-de-
large and well-developed; palate long and velopedwithshort, stout, andcurvedclaws.
wide, with well-developed and complex Pes rather short and broad, although meta-
posterolateralpits,butwithrathershortand tarsusis nearlytwiceaslongasdigitIII; the
posteriorlybroadenedincisiveforamina;al- heel is haired and the naked sole begins at
isphenoid strut absent; carotid arterial cir- about V4 the length of the plantar surface
culation of Pattern 3 (of Voss 1988); sub- (notincludingthe digits); outerdigits short-
squamosal fenestra reduced to totally oc- er than the middle three (with the claw ofI
cluded, tegmen tympani either not in con- extending to orjust past the base ofII and
tact with or only touches, but does not that of V to the proximal phalax of IV);
overlap, squamosal; incisors small, narrow, conspicuoustuftsoflong, silveryhairspres-
proodont to orthodont; upper and lower ent at dorsal bases ofclaws extending past
molarssmall,pentalophodont,butwithlow the tips, but the claw is visible from above;
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108, 2 321
Fig. 1. PhotographofalivingScolomysjuruaense, newspecies(INPA 2490, BarroVermelho, leftbankRio
Jurua, Amazonas, Brazil).
claws short, stout (about twice as long as fined beaded ledges overhanging margins
deep)andstronglycurvedalongtheirdorsal from middle of frontals, continuing along
surface; plantar pads five to six (thenar and posterior margins oforbit and onto brain-
four interdigital pads large, fleshy, and al- case just above the squamoso-parietal su-
ways present; hypothenar pad eitherabsent ture as weakly to moderately-developed
oronlyweaklydeveloped). Tailshorterthan temporalridges. Braincasedistinctlyround-
head-and-body, appearing sparsely haired, ed and globular in appearance, dominating
without a terminal tuft or pencil of long dorsal aspect ofskull (length ofbraincase V2
hairs; 15-18 scale annuli per cm at mid- lengthofskull). Nasals somewhat expanded
length; annular hairs broad, blackish, and andtaperposteriorly toa median point that
2.5-4 scale rows in length, but sparsely dis- terminates well behind the premaxillary-
tributed so that the tail scales are conspic- frontal sutures. Interparietal large, V2 to Vs
uous. The overall impression is ofa small- as deep as wide.
bodied, short-tailed, andshort-earedmouse In lateral view, nasals extend only to or
with a broad head, but short and pointed just barely beyond anterior curvature ofin-
rostrum and very spiny fur (Fig. 1). cisors. Zygomatic plate narrow, vertical to
Skull, indorsalview, with shortandbroad slightly angled posteriorly from base, and
or tapering rostrum flanked by shallow, without distinct, free dorsal edge (thus, the
barely perceptible zygomatic notches; na- zygomatic notch is shallow when viewed
solacrimal capsules expanded (especially so fromabove). Zygomaticarch thinwithjugal
in S. melanops, Fig. 2); interorbital region reduced. Postglenoid foramen moderate to
broad and hourglass-shaped, with well-de- small; hamular process ofsquamosal stout;
322 PROCEEDINGSOFTHEBIOLOGICALSOCIETY OFWASHINGTON
Fig, 2. Dorsal, ventral, and lateral views ofcranium, lateral view ofleft mandible ofScolomys melanops
Anthony, USNM 513581, adult male. Scalebarequals 10 mm.
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108, 2 323
subsquamosal foramen reduced to totally curved posterior projection; capsular pro-
occluded; mastoid fenestra very small to cesses of lower incisor alveoli weakly de-
lacking. Tegmen tympani ofperiotic either veloped; lower incisors thin, elongate, with
doesnotcontactorabuts,butdoesnotover- enamel essentially devoid ofpigment. Up-
lap, the squamosal. Tympanic bullae small per incisors ungrooved, with yellow to pale
andinflatedventrally onlytolevel ofmolar yellowenamel; small,deeperthanwide,and
series. proodont(S. melanops, Fig. 2)to orthodont
In ventral view, incisive foramina mod- {S. ucayalensis and the new species de-
erate in size (occupying about 60% ofdias- scribed below).
temal distance) and distinctly tear-drop in Maxillary tooth rows slightly convergent
shape, pointed anteriorly with diverging posteriorly,andangledobliquelydownward
sidesandexpanded,roundedposteriormar- and outward at about a 40 degree angle.
gins;premaxillary-vomerineseptumgreatly Teeth ofnearly all known specimens mod-
swollen and nearly filling the entire cavity erately to well-worn, and, as the cusps are
whenviewedventrally. Bonypalatelongand low, even a little wear obscures surface to-
wide (sensu Hershkovitz 1962), without a pography. Molars small, always longer (an-
medial ridge or palatal excrescences, with teriorly-posteriorly)thanwide,andforming
only weakly evident lateral folds, but with a graded series with the third molar greatly
large and complex posterolateral pits. The simplified.Upperteethpentalophodontwith
mesopterygoidfossawidewithparallel sides principal cusps arranged transversely and
and a rounded or squared anterior margin, slightly obliquely; labial and lingual reen-
ending well behind the third molars; bony trant folds do not interdigitate, or contact,
roof of fossa complete, or perforated only with majorlabial folds ofMl and M2 (par-
by barely perceptible sphenopalatine va- aflexus and metaflexus) deep, extending at
cuities along the presphenoid. Paraptery- least % across the tooth, lingual folds re-
goid fossae well developed, with lateral duced, with protoflexus only evident as a
margins straight to slightly convex and shallow lateral indentation in Ml and not
strongly divergent towards the bullae, de- visibleatallinM2. ProcingulumofMl and
voidofvacuitiesexceptforasmallforamen ml well-developed but not divided into
ovale, and moderately excavated, certainly separateanterolabialandanterolingualcon-
notflatinappearance.Alisphenoidstrutab- ules (no anteromedial flexus [-id]); antero-
M
sent, but only foramen ovale is present lat- flexus on 1 absent so that anteroloph not
erally; without anterior opening of alis- separated from labial anteroconule; anter-
phenoid canal. A shallow trough where the oloph of M2 well developed; distinct me-
masticatory-buccinatorbranch ofthe max- solophspresentandextendingtolabialmar-
illarynervecoursesvisible; itemanatesfrom gin ofallthree molars; posteroloph well de-
anterior margin ofthe foramen ovale and veloped on Ml but barely perceptible on
obliquely crosses the alisphenoid onto the M2 and absent on M3. Paracone and me-
squamosal. Facial circulation apparently tacone ofM1 and M2 tall and well devel-
derivedonlyfromtheinternalcarotidartery oped with protocone and hypocone pro-
(Pattern 3, ofVoss, 1988), as indicated by portionatelyreducedinsizeandmuchlower
a greatly reduced to absent stapedial fora- in topography; only paracone and weakly-
men,nosquamoso-alisphenoidgroovealong developed protocone present on M3.
intemo-lateral wall of braincase, and no Content and distribution. —The genus
sphenofrontal foramen (signs of supraor- Scolomys comprises two described species,
bital branch ofstapedial artery). the known ranges ofwhich are geographi-
Mandible short and stout; coronoid pro- cally restricted within the western Amazon
cess short with a weakly to moderately- Basin (Fig. 3). The type species, S. melan-
324 PROCEEDINGSOFTHE BIOLOGICALSOCIETYOFWASHINGTON
80O 70°
Fig. 3. Distributionalrecordsofspinymice,genusScolomys. Circles = S. melanopsAnthony,triangle = S.
ucayalensisPacheco, andsquares = S.juruaensenewspecies(numberedasinlistofspecimens; seetext).
ops, isknownfromthreelocalitiesineastern Scolomysjuruaense, new species
Ecuador: thetype localityatMera, 1160 m,
Pastaza Province (holotype and five para- Holotype.-MVEG 23824 (Museo Par-
types in the American Museum ofNatural aense Emilio Goeldi, Belem, Para, Brazil),
History, New York [AMNH], and three adult female, collected on 19 September
topotypes in the Natural Museum ofNat- 1991 by J. L. Patton (original number
ural History, Washington D.C. [USNM]); 15570); skin with skull and mandibles, in
Huamani, Volcan Sumaco, Napo Province good condition, plus liver tissue preserved
(aboveMera,onespecimeninthecollection both deep frozen and in ethyl alcohol. Tis-
ofthe Escuela Politecnica Nacional, Quito suesaremaintainedinthecollectionsofthe
[Albuja, 1991]), and Limoncocho, 250 m, Museum ofVertebrate Zoology, University
Napo Province (3 specimens in USNM). ofCalifornia, Berkeley.
Scolomys ucayalensis Pacheco is known Typelocality.—SQrm%2i\ Condor, leftbank
from two specimens from its type locality, Rio Jurua, Amazonas, Brazil 70°5rw,
Centro de Investigaciones "Jenaro Herre- 6°45'S. Obtained in tree-fall slash distur-
ra," 2.8 km E Jenaro Herrera, Depto. Lo- bance in otherwise primary terra firme (or
reto, right bank ofRio UcayaH, Peru, 135 upland, non-seasonally flooded) forest.
m. A third species from four localities in Paratypes.—The total known sample of
western Amazonia of Brazil is described S.juruaenseconsistsoftheholotypeand 22
here; it may be known as additional specimens that are deposited in
VOLUME 108, NUMBER2 325
the Colegao de Mamiferos, Institute Na- Amazones (Fig. 3); all localities are below
m
cional de Pesquisas da Amazonia (INPA); 400 in elevation.
Museu Paraense Emilio Goeldi (MPEG); Etymology. —The name refers to the
and Museum of Vertebrate Zoology, Uni- knowndistributionalongtheRioJurua, the
versityofCaliforniaatBerkeley(MVZ),list- largest white-water tributary of the Rio
edherebylocality(numberedasinthemap, Amazonaswithanoriginextralimitaltothe
Fig. 3): Brazil-Acre: (1) Sobral, left bank Andean cordillera.
Rio Jurua, 72M9'W, 8°22'S-INPA 2485, Diagnosis.—A small-bodied mouse (Ta-
adultfemale, skinwithskull, carcassinfluid ble 1) with short, nearly naked tail (83% of
plus karyotype; INPA 2486, adult male, in body length); short, broad headwith point-
fluid plus karyotype; MPEG 24023, adult ed snout (Fig. 1); short and relativelybroad
female, skin with skull, carcass in fluidplus hindfeet; hypothenarpadgreatlyreducedto
karyotype; MPEG 24024, aduU female, in absent (minutely present in 15 of 23 spec-
fluidpluskaryotype; MVZ 183172,juvenile imens)butthenarandinterdigitalpadswell-
female, in fluid plus karyotype. Amazonas: developed; small and rounded ears; dorsal
(2)typelocality-MPEG24019,adultmale, color varying from a grizzled pale reddish-
skin and skull; MPEG 24020, adult male, brown (Sudan Brown to Antique Brown;
MVZ
skinandskuflpluskaryotype; 183167, capitalizedcolortermsfromRidgway 1912)
adult female, skin and skull; MVZ 183168, to dark reddish-black (Raw Umber) finely
adult male, skin and skull plus karyotype; streaked with black; with rounded and in-
(3) Penedo, rightbank Rio Jurua, 70°45'W, flated braincase; short, basally-broad ros-
6°50'S-INPA 2487, adult male, skin and trum that tapers distally; narrowed and
skull; INPA 2488, adult male, body in fluid straight zygomatic arches; narrow but long
MPEG
with skull extracted; 24022, adult orbital openings; subsquamosal fenestrato-
female, body in fluid with skull extracted; tally occluded by stout hamular process of
MVZ
183165,adultmale,bodyinfluidwith squamosal; shortanddistallybroadincisive
MVZ
skullextracted; 183166, adultfemale, foramina with sides distinctly 'stepped';
skinand skull; and(4) Barro Vermelho, left wide mesopterygoidfossawithparallel sides
bank Rio Jurua, 68°46'W, 6°28'S-INPA and squared, as opposed to rounded, ante-
2489, subadult male, skin and skull plus rior margin (Fig. 4); and 2N =50. Other
karyotype; INPA 2490, adult female, skin characteristics are as listed above for the
and skullpluskaryotype; INPA 249 adult genus.
1,
female, skinandskullpluskaryotype;INPA Measurements of holotype. —Measure-
2492, adultmale, skinandskull, karyotype; ments are in millimeters and weight (mass)
MPEG
24021, adult male, skin and skull in grams; external measurements are those
MVZ
plus karyotype; 183169, subadult recordedonthespecimenlabelandbilateral
MVZ
male, skin and skull plus karyotype; measurements were taken on the right side
183170, adultmale, in fluidpluskaryotype; withdigitalcalipers: Totallength, 160; head
MVZ
and 183171, adultmale, influid. Liv- andbody, 86; tail, 76; hindfoot(withclaws),
er tissues preserved in 95% ethyl alcohol 21; ear (from notch), 16; condyloincisive
and frozen at -76°C are available for all length(CIL), 21.21; zygomaticbreadth(ZB),
specimensandaredepositedintheMuseum 12.42; braincase breadth (BB), 1 1.59; least
ofVertebrate Zoology, as are chromosome interorbital breadth (IOC), 5.84; rostral
slides for all karyotyped specimens. length (RL, taken from anterior orbit to tip
Distribution.—Y^no^n from three locali- ofnasals), 7.98; nasallength(NL), 8.60; ros-
ties on the left and one on the rightbank in tral width-1 (RW-1, across nasolacrimal
the central and upper reaches of the Rio capsules), 4.86; rostral width-2 (RW-2, at
Jurua in the Brazilian states of Acre and premaxillo-maxillary suture), 3.61; orbital
2
326 PROCEEDINGSOFTHEBIOLOGICALSOCIETYOFWASHINGTON
Table 1.—SelectedmeasurementsofspinymiceofthegenusScolomys(mean oneStandarderrorandrange,
with sample size).
Variable S. melanops S.ucayalensis S.jumaense
Total length 153.9 ± 3.01 144.0 152.4 ± 1.9
(138-167) (142-163)
«= 10 n= 1 n= 11
Tail length 62.8 ± 2.06 60.0 69.0 ± 1.50
(55-77) (26-76)
n= 10 n= 1 «= 11
Hindfootlength 20.9 ± 0.31 18.0 20.6 ± 0.20
(20-23) (19-22)
«= 10 n= 1 n= 16
Earheight 15.0 13.0 15.6 ±0.18
(15-17)
n = 3 n= 1 «= 16
Condyloincisivelength 19.87 ± 0.30 19.41 ± 0.47 20.43 ± 0.22
(18.51-20.67) (18.94-19.89) (18.60-21.97)
71= 7 n = 2 «= 16
Zygomaticbreadth 12.42 ±0.18 11.52 ± 0.25 12.13 ± 0.13
(11.37-12.90) (11.27-11.77) (11.18-13.30)
n = S n = 2 n=l6
Braincasebreadth 11.12 ± 0.07 11.41 ± 0.13 11.39 ± 0.11
(10.82-11.41) (11.29-11.54) (10.54-12.33)
« = 8 « = 2 n=l6
Least interorbital 4.96 ± 0.07 5.58 ± 0.09 5.59 ± 0.09
constriction (4.77-5.45) (5.49-5.68) (4.55-6.13)
n = 9 n = 2 «= 16
Rostrallength 6.92 ± 0.16 7.86 ± 0.11
(6.34-7.78) (6.93-8.48)
n = 9 n= 15
Nasallength 7.64 ± 0.10 7.69 ± 0.27 8.31 ± 0.11
(7.16-8.14) (7.42-7.96) (7.83-9.34)
n = 9 n = 2 A2= 15
Rostralwidth—1 4.78 ± 0.07 4.81 ±0.07
(4.47-5.10) (4.36-5.40)
n = 9 «= 16
Rostralwidth— 3.48 ± 0.08 3.64 ± 0.06
(3.21-3.84) (2.79-4.05)
n = 9 n= 16
Orbital length 6.90 ± 0.10 7.38 ± 0.09
(6.45-7.21) (6.67-7.89)
n = S n=\6
Diastemalength 5.84 ± 0.09 5.59 ± 0.21 6.23 ± 0.09
(5.50-6.34) (5.38-5.80) (5.73-6.75)
n = 9 n = 2 «= 16
Maxillarytooth 2.70 ± 0.05 2.81 ± 0.13 2.66 ± 0.04
rowlength (2.49-2.93) (2.69-2.94) (2.31-2.88)
n = 9 n = 2 «= 16
VOLUME NUMBER
108, 2 -ill
Table 1.—Continued.
Variable S. melanops S. ucayalemis S.juruaense
Incisiveforamenlength 3.76 ± 0.09 3.765 ± 0.001 3.94 ± 0.07
(3.31-4.19) (3.76-3.77) (3.17^.32)
n = 9 n = l «= 16
Palatalbridgelength 9.03 ± 0.19 8.65 ± 0.05 9.14 ±0.12
(8.42-9.69) (8.60-8.70) (8.28-9.87)
n = 6 n = 2 «= 16
Alveolarwidth 4.41 ± 0.07 4.475 ± 0.001 4.62 ± 0.05
(4.15^.74) (4.47-4.48) (4.29-4.96)
n = 8 n = 2 «= 16
Occipitalcondylewidth 5.82 ± 0.07 6.01 ± 0.06
(5.54-6.14) (5.64-6.46)
n = l A2= 16
Mastoidbreadth 10.28 ± 0.15 10.29 ± 0.08
(9.67-10.70) (9.70-10.73)
«=
16
Basioccipitallength 3.19 ± 0.06 3.23 ± 0.05
(2.98-3.38) (2.83-3.60)
n = l «= 16
Mesopterygoid 3.30 ± 0.18 3.61 ± 0.05
fossalength (2.98-3.68) (3.35-3.92)
n = 4 n= 16
Mesopterygoid 1.79 ± 0.09 1.97 ± 0.03
fossawidth (1.38-2.15) (1.78-2.20)
n = l «= 16
Zygomaticplatewidth 1.59 ± 0.06 1.71 ± 0.03
(1.42-1.81) (1.54-1.93)
n = l «= 16
Cranial depth 8.32 ± 0.12 8.89 ± 0.09
(7.87-8.72) (8.18-9.49)
n = l «= 16
length(OL), 7.74; maxillarydiastemalength imens of S. juruaense and of S. melanops
(D), 6.43; maxillary tooth row length and S. ucayalensis.
(MTRL), 2.82; incisive foramen length Description.—r>orsa\ coloration uniform
(IFL),4.00;palatalbridgelength(PBL), 9.68; from snout to rump, but individuals vary
alveolar width (AW, outside ofMl), 4.58; bothwithin andamonglocalitiesfrom griz-
occipital condyle width (OCW), 6.46; mas- zled pale reddish-brown to dark reddish-
toid breadth (MB), 10.73; basioccipital black; ventral coloration uniformly clear
length (BOL), 3.44; mesopterygoid fossa gray. Foreandhindfeetclotheddorsallywith
length (MPFL), 3.48; mesopterygoid fossa stiffwhite hairs; ungual tufts ofthin, silvery
width(MPFW), 2.13;zygomaticplatewidth hairs extend to orjust beyond tip ofclaws.
(ZPW), 1.66; cranialdepth(CD), 8.97; mass, Otherwiseasdescribedforthegenus,above.
26 grams. Mostfeaturesofcranial morphology(Fig.
Additional measurements.—^qq Table 1 4 and Table 1) are given above in the di-
for additional measurements ofadult spec- agnosis, or detailed under the extended de-
328 PROCEEDINGSOFTHEBIOLOGICALSOCIETYOFWASHINGTON
Fig.4. Dorsal,ventral,andlateralviewsofcranium,lateralviewofleftmandibleoftheholotypeofScolomys
juruaense, new species, MPEG 23824, adultfemale (original numberJLP 15570). Scalebarequals 10 mm.