The insectivores of the Réserve Spéciale d'Anjanaharibe-Sud, Madagascar

23 Pages·1998·10.4 MB·

by  Steven M Goodman

Chapter 10
The Insectivores of the Reserve Speciale
d'Anjanaharibe-Sud, Madagascar
Steven M. Goodman1 and Paulina D. Jenkins2
Abstract
Insectivores were surveyed on the eastern slopes of humid forest in the Reserve Speciale
d'Anjanaharibe-Sud at four elevational zones between 875 and 1950 m. Eleven species of
tenrecs (Setifer, Tenrec, and nine species of Microgale) were documented within the reserve.
An additional four species were also recorded on the western side of the reserve.
No species of insectivore occurred across the complete elevational transect. Setifer setosus
and Microgaleprincipula were restricted to the 875 m zone. The greatest species richness was
m
found at 1260 and 1550 with seven species ofTenrecidae (all Microgale). Microgale dobsoni
was captured only at 1260 m. Microgale soricoides, M. talazaci, and M. gymnorhyncha were
found in montane forest at 1260 and 1550 m, whereas M. parvula and M. cowani occurred in
these two zones and approaching the summit at 1950 m. One species collected in montane
forest ofthe reserve appears to be unrecognized and is described herein. Combining all sources
of information, 16 species of Insectivora have been recorded within the reserve, 12 of which
belong to the genus Microgale.
Resume
Une enquete sur les insectivores de quatre zones situees sur un transect altitudinal entre 875
et 1950 m le long du versant oriental de la foret humide sempervirente de la Reserve Speciale
d'Anjanaharibe-Sud a ete realisee. Onze especes de tenrecs (Setifer, Tenrec, et neuf especes
de Microgale) ont ete trouvees dans la reserve. Quatre especes supplementaires de Microgale
ont ete repertoriees sur le versant occidental de la reserve.
Aucune espece d'insectivore n'a ete trouvee sur l'ensemble des stations du transect altitu-
dinal. Setifersetosus et Microgaleprincipula presentaient une distribution restreinte a la station
situee a 875 m d'altitude. La plus grande diversite specifique a ete rencontree a 1260 et 1550
m avec un total de sept especes de Tenrecidae (toutes appartenant au genre Microgale). Mi-
crogale dobsoni etait capturee seulement a 1260 m d'altitude, Microgale soricoides, M. tala-
zaci, et M. gymnorhyncha ont ete trouvees dans la foret d'altitude a 1260 et 1550 m, alors que
M. parvula et M. cowani etaient rencontrees dans ces deux zones et atteignaient presque les
zones sommitales en etant presentes a 1950 m d'altitude. Une espece collectee dans la foret
d'altitude de cette reserve semble etre une nouvelle espece et fait ici l'objet d'une description.
En combinant toutes les sources d'information, 16 especes d'insectivores ont ete inventorizes
au sein de la reserve, parmi lesquelles 12 appartiennent au genre Microgale.
1 Field Museum ofNatural History, Roosevelt Road at Lake Shore Drive. Chicago. IL 60605 U.S.A.
:The Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom.
GOODMAN & JENKINS: INSECTIVORES 139
Introduction collected at the lower altitude, while eight other
species were found in the montane and upper
Before the current study, little was known montane zones. Information on these nine species,
about the small mammal community of the Re- including one believed to be undescribed, as well
serve Speciale (RS) d'Anjanaharibe-Sud. The as other species of Tenrecidae found within the
only Insectivora listed by Nicoll and Langrand reserve, is given below.
(1989) for the reserve are members ofthe endem-
ic family Tenrecidae, Tenrec ecaudatus (Schreber,
1777) and Setifer setosus (Schreber, 1777). The
Soricidae, the otherfamily ofInsectivora found in Materials and Methods
Madagascar, represented on the island by Suncus
madagascariensis (Coquerel, 1848) and the intro- Two principal techniques were used to trap in-
duced Suncus murinus (Linnaeus, 1766) has not sectivores in the four surveyed transect zones (at
m
been recorded from the reserve. In the nearby Re- 875, 1260, 1550, and 1950 above sea level):
serve Naturelle Integrate (RNI) de Marojejy, a pitfall traps and standard small mammal live
high mountain zonejust across the Andapa basin traps. The pitfall traps were composed of 11 plas-
from the RS d'Anjanaharibe-Sud, T. ecaudatus, tic buckets (275 mm deep, 290 mm top internal
mm
Setifer setosus, Hemicentetes semispinosus (Cu- diameter, and 220 bottom internal diameter),
m
vier, 1798), Microgale talazaci (Major, 1896a),M. sunk in the ground at 10 intervals with the up-
pusilla (Major, 1896b), and M. cowani (Thomas, per rims flush with ground surface level. Small
1882) have been recorded (Nicoll & Langrand, holes (2 mm diameter) were drilled in the bottom
c1a9i8n9e),.aDusritieng"1thdeaMyisWsioonf FArnadnacpoa-A"ngwlaos-Avmiesirtie-d oplfastthiec bduricfktetfsentcoe,al1l0o0wmwatleorngdraanidnag0e..5 Am bhliagch,k
(Rand, 1936), and material ofM. talazaciwascol- was erected in a vertical position and stapled to
lected and is now deposited in the Museum Na- thin wooden stakes. The fence bottom was buried
mm
tional d'Histoire Naturelle, The Natural History 50 into the ground using leaflitteror soil and
Museum, and the American Museum of Natural positioned to run across the middle ofeach pitfall
History. Other than these records, little is known trap. Pitfall buckets were positioned at 10 m in-
about the insectivore community in the general tervals. Within each elevational zone, three lines
Andapa area. were installed (valley bottom, slope, and ridge
The current report is based on a small mammal crest). Each line was checked in the morning soon
survey recently undertaken by S. M. Goodman in after dawn and again in the late afternoon. After
the RS d'Anjanaharibe-Sud from October to No- rain the buckets were sponge-dried. A bucket in
vember 1994. The purpose of the present study place for a 24-hr period is referred to as a "buck-
was to document the distribution of Tenrecidae et-day" (dawn to dawn). This is the same tech-
along an elevational gradient on the slopes ofthe nique we have systematically used over the past
RS d'Anjanaharibe-Sud, specifically with regard few years in Madagascar (Raxworthy et al., 1994;
&
to altitudinal distribution, density, and species Jenkins et al., 1996; Raxworthy Nussbaum,
richness ofMicrogale (Thomas, 1882). 1996). The period of the survey coincided with
The genus Microgale is the most speciose of the season when all tenrecs are presumed to be
the tenrec generaendemic to Madagascar. The ge- active (Stephenson, 1994).
nus was revised by MacPhee (1987), who estab- In each elevational zone surveyed, trap lines
lished an effective taxonomy based chiefly on were in operation for a minimum of five nights.
dental morphology. During recent small mammal Each trap line consisted of Sherman live traps (9
surveys (Raxworthy & Nussbaum, 1994; Good- X 3.5 X 3 inches) and National live traps (16 X
man et al., 1996), numerous samples ofMicrogale 5X5 inches) in a ratio of4:1. Traps were baited
were collected, further increasing knowledge and daily, generally between 15:00 and 17:00 hr, with
allowing additional refinementofthe taxonomy of a fresh mixture offinely ground peanut butter and
the genus (Jenkins et al., 1996, 1997). corn grain mixed in proportions to make a paste.
The RS d'Anjanaharibe-Sud survey com- Traps were visited at least twice per day, once at
menced in lowland forest at 875 m, progressing dawn and in the late afternoon. A "trap-night" is
m
to montane forest at 1260 and 1550 and to up- defined as one trap in use for a 24-hour period
per montane forest at 1950 m. Only one species (dawn to dawn).
ofMicrogale, M. principula (Thomas, 1926), was Captured animals were either released or pre-
140 FIELDIANA: ZOOLOGY
pared as standard museum skins with associated upper molar, parallel to the long axis of
skulls and skeletons, fluid-preserved carcasses, or the skull
full skeletons. Voucher specimens are deposited WT = weight, measured in grams with Pesola
in the Field Museum ofNatural History, Chicago, spring scales; animals weighing less
and the Department de Biologie Animale, Uni- than 10 g were weighed to within 0.2
versite d'Antananarivo, Antananarivo. g, and those weighing between 10 and
100 g were weighed to within 0.5 g
Measurements Reproductive condition was recorded for males
as length X width ofthe testes and degree ofcon-
volution of the epididymis. Females were noted
Cranial measurements were taken using dial as nonperforate or perforate and as nonparous or
calipers and a microscope measuring stage. The parous, and the number and location of any em-
dSewnitnadllenrom(e1n9c7l6a)t,urBeutfloelrloawnsdtGharteoefnwMoilolds ((11997696)),, bmraymomsaranydfpolramcuelnatails psrceasresntweedreas rtehceornduemdb.erThoef
and MacPhee (1987). Dental notations are given paired axial, abdominal, or inguinal teats.
in parentheses in the text; premaxillary and max- The following age classes are recognized: "In-
illary teeth are denoted by uppercase letters, and fant" includes individuals in which the deciduous
Timamhneednisfboulillnoawtrhietnegeftlmheesaahrseourrdeefmnroeotnmetdspbrwyeeprlaeorwemedarcdcareasneoifal.esttpAeebrcs--. eaitrnautlpetsmeuodtl;uarrtehsedeapnrrteeimtuianoxfniulslaeandrd.y,t"hpJeaurvimeeotnlaiall,resa"nadirenbcalnsuoidtoecsfcuilipln-y-
breviations and definitions for these measure- dividuals in which the molars are fully erupted
ments (all in millimeters with the exception of and the deciduous antemolar dentition is erupted
weight, which is in grams) are as follows: and in the process of replacement by the perma-
nent teeth; cranial sutures are in the process of
BB = breadth of braincase, the greatest dis- fusing. The eruption sequence of the permanent
tance measured across the squamosals teeth has been subdivided into four stages by
CIL = condyloincisive length, cranial length MacPhee (1987); these stages have been accepted
from first upper incisorto occipital con- in this chapter unless otherwise stated. "Adult"
dyle includes individuals with fully erupted permanent
EL = ear length, measured from the notch at dentition; cranial sutures are generally fused, al-
the base of the ear to the distalmost though their position is more or less clearly
edge of the pinna marked.
HB = head and body length, measured from Other abbreviations used are as follows:
the tip of the nose to the distalmost
point of the body (at base of tail) PN = Pare National
HF = hindfoot length, measured from the RNI = Reserve Naturelle Integrate
back edge of the heel to the tip of the RS = Reserve Speciale
longest toe (not including claw) bm(nh) = Natural History Museum, London (for-
I1-P3 = length of anterior upper teeth, from an- merly British Museum (Natural Histo-
terior of first upper incisor to anterior ry)
of second upper premolar fmnh = Field Museum ofNatural History, Chi-
TL = tail length, measured from the base of cago
the tail (at right angles to the body) to mcz = Museum ofComparative Zoology, Har-
the end ofthe distalmost vertebra; does vard
not include terminal hair tufts mnhn = Museum National d'Histoire Naturelle,
TOTL = total length of body and tail, measured Paris
from the tip of the nose to the end of ummz = University of Michigan, Museum of
the distalmost tail vertebra; animal is Zoology, Ann Arbor
positioned on its back straight with ver- C/c = canine
=
tebrae parallel to ruler but not stretched d deciduous
=
out I/i incisor
UTL = upper toothrow length, from anterior of M/m = molar
=
first upper incisor to posterior of third P/p premolar
GOODMAN & JENKINS: INSECTIVORES 141
Systematic Section served on two occasions at 875 m and thrice at
1260 m. No specimen was collected. Nicoll and
Subfamily Tenrecinae Langrand (1989) also reported this species from
Setifer setosus (Schreber, 1777) the reserve.
—
Holotype Unk—nown.
Type Locality Mad—agascar. Microgale cowani Thomas, 1882
Referred Material fmnh 154033, 154034, —
154230, 154231, 154232, 154233, 154234, Holotype bm(nh) 82.3.1.25, adult female
154235: 6.5 km SSW of Befingitra, 14°45'S, body in alcohol, skull extracted, collected mid-
49°30'E, 875 m. — March to mid-February 1880 by the Reverend W.
Key Features (see Appendix 10-1, p. 161) Deans Cowan. —
Dorsum covered with spines. Skull moderatelyro- Type Locality Ankafana Forest, eastern Bet-
=
bust, dorsal profile curved in lateral view; rostrum sileo (Ankafana Ankafina, Fianarantsoa, and
deep and broad; interorbital region broad and Fianarantsoa Province, 21°12'S, 47°12'E; see
&
elongated; braincase short, supraoccipital crest MacPhee, 1987; Carleto—n Schmidt, 1990).
present. Two lower incisors present; dental for- Referred Material fmnh 154020, 154021,
mula 2/2 1/1 3/3 3/3 = 36; first upper incisors 154022, 154195: 9.2 km WSW of Befingitra
well developed, slightly shorter than upper ca- 14°44'S, 49°27'E, 1260 m; fmnh 154023, 154024,
nines; short diastemata on either side ofupperca- 154025, 154026, 154196, 154197, 154198,
nines and first lower premolar. — 154199, 154200, 154201, 154204: 11 km WSW
Population Structure and Reproduction of Befingitra, 14°44'S 49°26'E, 1550 m; fmnh
The sex ratio of females to males was 1:4. Mam- 154202, 154203, 154205, 154206, 154207: 12.2
mary formul—a: 1-2-2 (n = 2). km WSW of Befingitra, 14°44'S, 49°26'E, 1950
Remarks At 875 mfourSetiferwere obtained m.
in pitfall traps; five individuals were obtained in Key Feature—s (see Table 10-1 and Appendix
live traps. All of the latter group were captured 10-2, p. 161) Medium-sized Microgale, tail
on the ground, generally in areas with thick moderately short, shorter or subequal to HB. Pel-
ground leaflitter. Nicoll andLangrand (1989)pre- age dark brown dorsally, gray ventrally with a
viously reported this species from the reserve. It reddish brown wash; tail bicolored, dark brown
has a broad range across the island from Antsi- dorsally, sharply demarcated from paler reddish
ranana to the Tolagnaro and Toliara regions. buff venter. Skull medium in size, rostrum elon-
gated; pronounced diastemata separate teeth of
upper anterior dentition from first upper incisor
Tenrec ecaudatus Schreber, 1777 (II) to second upper premolar (P3), also on either
— side oflowercanine (c) and first lowermolar(p2).
Holotype Unk—nown. All elements of talonid ofthird lower molar (m3)
Type Locality Madagascar. — present, including hypoconid, entoconidridge, tal-
Key Features (see Appendix 10-1, p. 161) onid basin, and en—toconid.
The largest of the Tenrecinae. Dorsal pelage of Measurements External andcranial measure-
coarse, bristly hair intermixed with spines. Skull ments are pre—sented in Table 10-1.
elongated; rostrum with deep sockets in ventro- Variation No interpopulation variation in
lateral region of the premaxillae, which accom- size or pelage color was observed. —
modate the lower canines when thejaw is closed; Population Structure and Reproduction
interorbital region narrow, elongated; braincase The sex ratio of females to males was 1:1.5. The
short, narrow, angular, pronounced sagittal and ratio of adults to juveniles was 1:1.5. Juveniles
supraoccipital crests form deep posterodorsal were not significantly smaller than adults in body
flanges. Three lower incisors present; dental for- or cranial size, although they were clearly lighter
mula 2/3 1/1 3/3 3/3 = 38; upper and lower ca- in body weight (see Table 10-1). All but one of
nines very long, robust, and prominent; pro- thejuveniles weredentally immature, withallmo-
nounced diastemata on either side of upper ca- lars fully erupted andeitherwith afully deciduous
nines and posterior to lower canines; short diaste- anterior dentition or only the third incisors in the
mata posteri—or to first upper and lower premolars. process of replacement (stage 1 of MacPhee,
Remarks This widespread species was ob- 1987:13); the exception was a specimen at stage
142 FIELDIANA: ZOOLOGY
•*t (N
o
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= 2o 2§
n*~ mt7t idn ^ (70N0 —d
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—< r— rn
—
oq d
in
^•Eivi +1 >n ©*
m
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scarcely greater in crown height than P3. Lower many presumed derived morphological adaptations,
p2 caniniform. Talonid of m3 with low hypocon- particularly the longprehensiletail, andhave similar
id, hypoconulid well developed, narrow talonid cranial and dental morphologies. Although no phy-
basin, reduced entoconid ridge, and entoconid ab- logenetic analysis of the genus has been conducted
sent. — to date, we strongly suspect that these two taxa are
Measurements External andcranial measure- closely related and fill similarecological niches. On
ments are pre—sented in Table 10-1. the slopes ofthe RS d'Anjanaharibe-Sud, these two
Variation Marked variation in size between species replace one another, with principula occur-
populations was observed. Specimens from RS ring in lowland forest and longicaudata onthehigh-
d'Anjanaharibe-Sud are larger than those from er slopes. We have no evidence that they occur in
RNI d'Andringitra (see Jenkins et al., 1996) and microsympatry on the mountain. Toourknowledge,
PN de Mantady. — this is the second reported case ofthese two species
Population Structure and Reproduction occurring in close proximity; both species have also
The single juvenile had fully erupted molars but been recorded from PN de Mantady (see Jenkins,
completely deciduous anterior dentition and un- 1993).
fused premaxillary and basioccipital sutures. Two
adult females were collected during the survey;
both were perforate, and one was lactating. Mam- Microgaleprincipula Thomas, 1926
=
mary formul—a: 1-0-2 (n 1). Microgale sorella Thomas, 1926; MacPhee,
Remarks Microgale longicaudata is a wide- 1987
spread shrew tenrec known from scattered local- —
ities from PN de la Montagne d'Ambre in the Holotype bm(nh) 25.8.3.15, adult female,
north to the RNI d'Andringitra in the south (Jen- body in alcohol, skull extracted, collected by C.
kins et al., 1996). Although this sample is too Lamberton. —
small forvalidconclusions, the sizedifference be- Type Locality Midongy du Sud, SE Mada-
tween the small juvenile (fmnh 154005) and the gascar (Midongy Atsimo, 23°35'S, 47°01'E; see
large adults (fmnh 154006 and 154220) appears MacPhee, 1987). —
greater than that likely to be attributable to Referred Material fmnh 154003, 154004:
growth. In addition, the adult specimens from RS 6.5 km SSW ofBefingitra, 14°45'S, 49°30'E, 875
d'Anjanaharibe-Sud, in common with those from m.
Ankafina and Amboanara considered to represent Key Featu—res (see Table 10-1 and Appendix
M. longicaudata by Thomas (1918), are larger 10-2, p. 161) Medium-sizedMicrogale, tail very
than those from RNI d'Andringitra, PN de Man- long, more than twice as long as HB; distal por-
tady, and the other specimens from Ankafina con- tion of tail naked and transversely wrinkled on
sidered by Thomas to represent M. majori. Al- dorsal surface; fifth hind digit elongated, subequal
though MacPhee (1987) synonymized M. majori in length to second digit. Pelage distinctly bicol-
with M. longicaudata, this evidence tends to sup- ored, reddish brown dorsally, gray with buffwash
port the original view of Thomas (1918) that M. ventrally. Skull medium in size, rostrum moder-
majori may be a separate species distinguishable ately short and broad, braincase moderately nar-
by its smaller size from M. longicaudata. row. Short diastemata between II and 12, and on
The only individual of this species captured at either side ofC and P2, 12 and third upper incisor
m
1550 was obtained in a Sherman live trapplaced (13) more or less in contact; well-developed an-
m
on a moss-covered vine 1.5 above the ground. terior and posterior accessory cusps present on 12,
In the literature on Microgale longicaudata, there C, and P2; II greater in crown height than C; P4
has been speculation, based on external morphol- distinctly greater in crown height than P3. Lower
ogy (Thomas, 1918; Eisenberg & Gould, 1970; p2 moderately caniniform. Talonid of m3 with
MacPhee, 1987) and skeletal structure (Dobson, low hypoconid, well-developed hypoconulid,
1882), that its long and modified tail might have broad talonid basin, reduced entoconid ridge, en-
some prehensile capabilities. We are now able to toconid absent. —
confirm this ability: a captive animal was able to Measurements External andcranial measure-
dangle by the tip of its tail from a thin branch for ments are pre—sented in Table 10-1.
at least 10 sec (see Fig. 10-1) using only the very Variation The sample is too small for mean-
distal tip of its tail to grip the branch. ingful comments on variation. —
Microgale longicaudata and M. principula share Population Structure and Reproduction
GOODMAN & JENKINS: INSECTIVORES 145
Fig. 1. PhotographofMicrogalelongicaudata(fmnh 154005)capturedinthe 1260mzoneandhangingsuspended
by its distally prehensile tail. The photograph was staged in the sense that the animal's tail was manipulated as the
singlepointofcontact with the branch. Once the animal was released in thisposition, itwasable toremainsuspended
for more than 10 sec. (Photograph by Brian Fisher.)
—
The sample contained twojuveniles, one at stage Type Locality Environs of Diego-Suarez
2 and the other at stage 3 of dental development (Antsiranana, ca. 12°16'S, 49°18'E, see MacPhee,
(MacPhee, 1987); the sex ratio was 1:1. The testes 1987; probably Montagne d'Ambre, see Jenkins
of fmnh 1540047,Xin5whmimch P3 and p3 were erupt- et al., 1997). —
ing, measured with a convoluted epi- Referred Material fmnh 154007, 154217:
didymides, so the specimen was probably repro- 9.2 km WSW of Befingitra, 14°44'S, 49°27'E,
ductively active while still retaining some decid- 1260 m; fmnh 154008: 11 km WSW of Befingi-
uous teeth.— tra, 14°44'S, 49°26'E, 1550 m; fmnh 154218,
Remarks This species was previously knownto 154219: 12.2 km WSW of Befingitra, 14°44'S,
occur from the RS d'Ambatovaky (16°51'S, 49°26'E, 1950 m.
49°08'E) in the north-central portion of the eastern Key Featur—es (see Table 10-1 and Appendix
humid forest (Jenkins, 1992) to the Grotte 10-2, p. 161) Very small, TL slightly shorter
d'Andrahomana in the extreme south (MacPhee, than HB. Dorsal pelage dark brown, ventral pel-
1987). The specimens from the RS d'Anjanaharibe- agedark gray-brown, tail uniformdarkgray. Skull
Sud mark the most northerly locality to date from very small anddelicate, rostrum slender, braincase
which this species has been recorded. shallow and long, occipital condyles posterodor-
sally orientated. Diastemata between II and 12
Microgaleparvula G. Grandidier, 1934 and either side ofC and P2; anteriorand posterior
Microgale—pulla Jenkins, 1988 macacebsestorwyeecnuscpsanpdrespe2n.tToanlo1n2i,d13o,famn3d Pw2i.thDiawsetlel--
Holotype mcz 45465, juvenile male, body in developed hypoconulid but reduced hypoconid,
alcohol, skull extracted, collected by M. Drou- entoconid and entoconid ridge, and narrow, shal-
hard. low talonid basin.
146 FIELDIANA: ZOOLOGY
—
Measurements External andcranial measure- low, hypoconulid prominent, entoconid ridge and
ments are pre—sented in Table 10-1. talonid basin poor—ly defined, entoconid absent.
Variation There is no obvious interpopula- Measurements External andcranial measure-
tion variation in size or pelage coloration. — ments are pre—sented in Table 10-1.
Population Structure and Reproduction Variation No obvious variation in size is ev-
The sample contained four adults and one juve- ident. —
nile, and the sex ratio offemales to males was 1: Population Structure and Reproduction
1.5. The juvenile, which had a fully deciduous The ratio ofjuveniles to adults in the sample was
anteriordentition, was within the size range ofthe 1:2.3, and the sex ratio was 1:1. There was no
adults in most dimensions, except body weight, indication of sexual dimorphism in size in this
CIL, and UTL, in which it was smaller (see Table small sample, except in body weight, where the
10-1). One ofthe two adult females was lactating, females were notably heavier (20.5-25.5, mean
both were perforate, and the mammary formula 23.8 ± 2.05, n = 4 for males; 26.0-30.0, mean
was 1-0-2 (n = 1). The testes of one adult male 27.8 ± 1.65, n = 3 for females), although the
3X2 mm
measured with convoluted epididymi- sample is too small to be statistically significant.
des. The size range ofadults andjuveniles was similar,
Remarks—See Jenkins et al. (1996; 1997) for although the range and mean in body weight of
redefinition and augmented description of this the juveniles actually exceeded that of the adults
species as well as for information on its range. (see Table 10-1); it is suggested that this may be
This species is now known from the far north in an anomalous result due to the small sample size.
the PN de la Montagne d'Ambre (Raxworthy & One of the adult females was lactating and had
Nussbaum, 1994) to the extreme southern limit of two placental scars in the left oviduct and three
the eastern humid forest in the Vohimena Moun- scars in the right oviduct. Mammary formula: 1-
=
tains (ummz) and Anosyenne Mountains (fmnh). 1-2 (n 5).—
Remarks Two of the Microgale dobsoni ob-
m
tained in the 1260 zone were captured in Sher-
Microgale dobsoni Thomas, 1884 man traps. Both were taken on consecutive nights
Nesogale dobsoni Thomas, 1918 in the same trap placed on the ground next to a
— small tree with a hole in the base. OneM. talazaci
Holotype bm(nh) 84.10.20.1, immaturemale, was taken in the same trap set, which shows that
in alcohol, skull extracted. Collected February or these two species, at least on occasion, have over-
March 1884 by W.—Waters. lapping home ranges.
Type Locality Nandesen forest, Central Bet- This species is widespread and is now known
&
sileo (Nandihizana, 10 miles S of Ambusitra, from Manohilahy, 17°16'S, 48°01'E (Eisenberg
manuscript note in Thomas' private copy oforig- Gould, 1970), to Antampona (MacPhee, 1987).
inal description, archived in bm(nh); Nandihizana, The specimens from the RS d'Anjanaharibe-Sud
ca. 20 miles (30 km) SSW of Ambositra, see mark the northernmost record to date. This spe-
MacPhee, 1987; estimated as ca. 20°50'S, cies andM. talazaci, the largest shrew-tenrecs, are
47°10'E). — known to be sympatric at several sites, including
Referred Material fmnh 154015, 154016, RS d'Analamazaotra (Eisenberg & Gould, 1970),
154208, 154209, 154210, 154211, 154212, RS dTvohibe (MacPhee, 1987), and on the An-
154213, 154214, 154215: 9.2 km WSW ofBefin- karatra Massif (bm(nh), fmnh, and mnhn).
gitra, 14°44'S, 49°27'E, 1260 m.
Key Featu—res (see Table 10-1 and Appendix
10-2, p. 161) Large, TL subequal to or longer Microgale talazaci Major, 1896a
than HB. Dorsal pelage brown, venter gray with Nesogale talazaci Thomas, 1918
buff wash. Skull large and robust, sutures fused —
and obscure; rostrum moderately broad, interor- Holotype bm(nh) 97.9.1.107, adult female,
bital region long; braincase angular, superior ar- skin, skull, and skeleton. Collected 22 May 1896
ticularfacets very prominent, supraoccipital crests by C. I. Forsyth Ma—jor.
well developed; occipital region reduced. Diaste- Type Locality Forest of the Independant
mata between II and 12 and between 13 and C. Tanala of Ikongo, in the neighborhood of Vinan-
Upper II larger than 12, i2 considerably larger itelo, 1 day's journey S of Fianarantsoa, 21°44'S,
than canine. Talonid of m3 reduced, hypoconid 47°16'E.
GOODMAN & JENKINS: INSECTIVORES 147
— —
Referred Material fmnh 154017, 154224, Referred Material fmnh 154027, 154029,
154225, 154226: 9.2 km WSW of Befingitra, 154221, 154222, 154223: 9.2 km WSW of Befin-
W14S°4W4'So,f4B9e°f2i7ng'iEt,ra1,21640°4m4;'Sf,m4n9h°261'5E4,0181:55011m.km gkimtraW, S14W°44o'fS,Be4f9in°g2i7t'rEa,, 1142°6404'mS;,4f9m°n2h6'1E5,4013505:0m1.1
Key Featur—es (see Table 10-1 and Appendix Key Featu—res (see Table 10-1 and Appendix
10-2, p. 161) Very large, TL longer than HB. 10-2, p. 161) Size large, TL subequal to or lon-
Dorsal pelage brown, venter gray with reddish ger than HB. Pelage light buff brown dorsally,
buff wash. Skull very large and robust, sutures gray-brown ventrally with reddish buff wash.
fused and obscure; rostrum broad, interorbital re- Skull moderately large and robust, rostrum and
gion long, parallel sided; braincase angular, short interorbital region broad, braincase short and
relative to cranial length, superior articular facets broad; supraoccipital ridge present. First II mark-
very prominent, supraoccipital crests well devel- edly robust and pro-odont. First il and i2 robust
oped, occipital region very reduced, occipitalcon- and procumbent, i2 smaller than il but largerthan
dyles visible in dorsal view. Small diastemata be- c. First upper and lower premolars very small
tween II and 12 and between 13 and C. Upper II with a single root. Talonid ofm3 reduced to very
larger than 12, i2 considerably larger than canine. low hypoconid, oblique crest, and prominent hy-
Talonid ofm3 reduced, hypoconid low, hypocon- poconulid. —
ulid well marked, entoconid ridge and talonid ba- Measurements External andcranialmeasure-
sin poorly defined,—entoconid absent. ments are pre—sented in Table 10-1.
Measurements External andcranialmeasure- Variation There is no evidence of size vari-
ments are pre—sented in Table 10-1. ation in the small sample available. —
Variation There is no obvious variation in Population Structure and Reproduction
size. — The age structure in the sample consisted of one
Population Structure and Reproduction juvenile with a fully deciduous anterior dentition
The sample consisted of five adults, with a sex and five adults, and the sex ratio (males to fe-
ratio of 1:3 (females to males). The testes oftwo males) was 1:2. In size, the juvenile was at the
males measured 5X3 mm and 10X6 mm, both lower part of the adult range and weighed less
with convoluted epididymides. The female was than any ofthe adults (see Table 10-1). One adult
5X5 mm
perforate, wi—th a mammary formula of 1-1-2. male had testes measuring with con-
Remarks At 1260 m one Microgale talazaci voluted epididymides. Mammary formula: 1-0-2
was trapped in a Sherman trap placed on the (n = 1); 1-1—-2 (n = 2).
ground at the base of a small tree with a hole in Remarks This species is now known from
its base. The only individuals ofthis species cap- three localities, the type locality in the PN de
tured within the 1550 m elevational zone were Mantady (18°51'S, 48°27'E), the RNI d'Andrin-
taken on the ground in Sherman live traps; one gitra (Jenkins et al., 1996), and the RS d'Anjana- j
individual was collected in a trap placed at the haribe-Sud, which marks the northernmost record
opening ofa small hole undera large boulder, and to date.
a second individual was collected at the base ofa
smalltreewith acavity undertheroots.Microgale
talazaci is known from humid forests at a range Microgale gymnorhyncha Jenkins, Goodman
of elevations from the Antsiranana region south and Raxworthy 1996
to Vondrozo (MacPhee, 1987) and west to the Microgale gracilis (Major): MacPhee, 1987,
Sambirano (bm(nh)). in part
—
Holotype fmnh 151807, adult female in al-
Microgale soricoides Jenkins, 1993 cohol, skull extracted (field number SMG 6697),
— collected 13 December 1993 by S. M. Goodman
Holotype bm(nh) 91.565, adult male in al- and C. J. Raxwort—hy.
cohol, skull extracted. Collected 13 April 1991 by Type Locality 38 km S of Ambalavao, RNI
C. J. Raxworthy. — d'Andringitra, on ridge E of Volotsangana River,
Type Locality Mantady National Park (PN Fianarantsoa Province, 22°11'39"S, 46°58'16"E,
de Mantady), ca. 15 km north of Perinet (Anda- 1625 m. —
sibe), 18°51'S, 48°27'E, in primary rain forest, Referred Material fmnh 154028, 154216:
1100-1150 m. 9.2 km WSW of Befingitra, 14°44'S, 49°27'E,
148 FIELDIANA: ZOOLOGY