Miniopterus brachytragos, Goodman & Maminirina & Bradman & Christidis & Appleton, 2009

Goodman, Steven M., Maminirina, Claudette P., Bradman, Helen M., Christidis, Les & Appleton, Belinda, 2009, The Use of Molecular Phylogenetic and Morphological Tools to Identify Cryptic and Paraphyletic Species: Examples from the Diminutive Long-fingered Bats (Chiroptera: Miniopteridae: Miniopterus) on Madagascar, American Museum Novitates 3669, pp. 1-36 : 9-17

Miniopterus brachytragos , new species

Figures 3 , 4A–C , 5 ; tables 3–5

HOLOTYPE: Field Museum of Natural History ( FMNH) 175840 collected by S.M. Goodman (field number SMG 13040) on 9 October 2002. The skull is in an excellent state. Before preservation of the specimen in formaldehyde, the skull was removed, conserved in dilute ethanol, and then cleaned using Dermestidae beetles. Pectoral muscle samples were saved in lysis buffer; this animal was sequenced and was used in the phylogenetic analysis presented herein (fig. 2; table 1). The specimen has a full adult dentition and the basisphenoid-basioccipital sutures are completely fused.

Measurements are in mm and body mass in g. Total length, 86; tail length, 39; hind foot length, 6; tragus length, 4; ear length, 10; forearm length, 37; mass, 4.3; greatest skull length, 13.3; greatest zygomatic breadth, 7.0; postorbital breadth, 3.1; mastoid breadth, 7.1; greatest braincase width, 6.5; lachrymal width, 3.5; palatal length, 6.4; mandible length, 9.0; cranial toothrow, 5.9; upper canine-molar toothrow, 5.0; width across upper canines, 3.5; width across third upper molars, 4.9 (tables 3–5).

TYPE LOCALITY: Madagascar: Province de Mahajanga, Réserve Naturelle Intégrale de Namoroka [status subsequently changed to Parc National], Forêt d’Ambovonomby , 26 km NW Andranomavo, 16 ° 28.29S, 45 ° 20.99E, 200 m above sea level .

DIAGNOSIS: A notably small member of the genus Miniopterus , with relatively short and nondense pelage. The dorsal fur is medium to slightly dark brown in color and the ventral +

analysis) and bootstrap support (ML, NJ, and MP analyses) and are indicated on the major nodes only (Bayesian/ML/NJ/MP). Labels include collecting locality and catalog number, sample identification number or Genbank accession number. The * indicates a missing NJ bootstrap value. Sample FMNH 5650 was basal to both M. petersoni and Clade 1, only in the NJ analysis. This may be an artifact due to the very short length of this sequence (160 bp from old museum specimen). Within Clade 2 there are several individuals that are not illustrated and share a haplotype with FMNH 175877 and in Clade 4 there is one individual that shares a haplotype with FMNH 175991; these are identified in table 1. Within Clade 2, FMNH 175840 is the holotype of M. brachytragos and within Clade 4, FMNH 173197 is the holotype of M. mahafaliensis .

(FMNH 202523). Note the very small tragus. (Photograph by Manuel Ruedi.)

hairs are tipped with a dark buff. Uropatagium with relatively short and dense fur on the majority of its dorsal surface, being more obvious on the proximal half. The forearm length of the holotype is 37 mm and ranges in the type series from 35–38 mm (mean 5 36.6 mm). Tragus is notably short and thick, with rounded to slightly pointed tip, 4 mm in the holotype and ranges from 3– 4 mm in the type series (mean 5 3.9 mm), the distal portion having a few long hairs difficult to see with the naked eye. The cranium has a sagittal crest that terminates before the parietals; a short and rectangular rostrum; deep, wide, and long nasal sulcus; and broad Ushaped palatal emargination.

PARATYPES: Province de Mahajanga, Réserve Naturelle Intégrale de Namoroka [status subsequently changed to Parc National], Forêt d’Ambovonomby , 26 km NW Andranomavo, 16 ° 28.29S, 45 ° 20.99E, 200 m, 9–10 October 2002 ( FMNH 175846 , 175847 , 175850– 175852 , 175856 ; same locality as the holotype) ; just outside limit of Réserve Naturelle Intégrale de Namoroka [status subsequently changed to Parc National], along Ampandra River , 22 km NW Andranomavo, 16 ° 26.4429S, 45 ° 24.7239E, 120 m, 11 October 2002 ( FMNH 175864 , 175865 , 175867 ) ; Réserve Naturelle Intégrale de Namoroka [status subsequently changed to Parc National], near source of Mandevy River , 32 km NW Andranomavo, 16 ° 22.89S, 45 ° 20.79E, 100 m, 14–15 October 2002 ( FMNH 175869– 175875 , 175877 , 175879–175885 ) ; Parc National de Bemaraha, south bank Manambolo River, near Tombeau Vazimba , 3.5 km E Bekopaka, 19 ° 08.49S, 44 ° 49.79E, 100 m, 2 December 2001 ( FMNH 172867 ) . Province d’Antsiranana, Nosy Komba, 0.9 km SW Ampangorinana, on trail to Station Forestière d’Antanampoera , 13 ° 26.8359S, 48 ° 20.4669E, 100 m, 14 February 2006 ( FMNH 188651 ) ; Forêt de Binara, near Analamazava River , 7.5 km SW Daraina (village), 13 ° 15.39S, 49 ° 37.09E, 325–600 m, 5 November 2001 ( FMNH 172685 , 172686 ) . Province de Toamasina, Masoala Peninsula, 1.8 km S Ambanizana (village), 15 ° 38.2919S, 49 ° 57.9449E, 5 m, 26 November 2007 ( FMNH 202523 ) .

DISTRIBUTION: Known to occur in several different biomes on Madagascar, from the Masoala Peninsula in the northeast, the Daraina region in the central northeast, and in the karstic zones of the Namoroka and Bemaraha massifs. It has also been found on the near-shore island of Nosy Komba.

DESCRIPTION: A small Miniopterus with tail length less than one-half the total length (table 3). The forearm length ranges from 35– 38 mm, and hind foot from 5–6 mm. In the holotype and the type series, the body fur is relatively short and not particularly dense. The dorsal hairs are medium to slightly dark brown in color and the ventral hairs are tipped with a dark buff, giving a slightly mottled appearance (fig. 3). Wing membranes are medium brown, grading into a slightly lighter brown on the plagiopatagium and uropatagium; these membranes attaching to the femur at a position superior to the ankle joint. The uropatagium has a notable covering of hair across its surface, being more obvious on the dorsal surface toward the proximal half and sparser on the ventral surface.

The dorsal surfaces of the ring-shaped ears have a fur covering across much of their surface and extending nearly to the distal margin, which is noticeable with the unaided eye, and the ventral surface is virtually naked

TABLE 3 External measurements (in mm) and mass (in g) of the different diminutive species of Miniopterus on Madagascar that were previously considered to be M. manavi All specimens are adults, the sexes are combined, and measurements are presented as mean ± standard deviation (minimum, maximum, number of specimens). Measurements were made by SMG, other than those in brackets. For measurements of M. petersoni see Goodman et al. (2008). TABLE 4 Cranial measurements (in mm) of the different diminutive species of Miniopterus on Madagascar that were previously considered to be M. manavi All specimens are adults, the sexes are combined, and measurements are presented as mean ± standard deviation (minimum, maximum, number of specimens). See Methods for explanation of variable acronyms. For measurements of M. petersoni see Goodman et al. (2008). TABLE 5 Dental measurements (in mm) of the different diminutive species of Miniopterus on Madagascar that were previously considered to be M. manavi All specimens are adults, the sexes are combined, and measurements are presented as mean ± standard deviation (minimum, maximum, number of specimens). See Methods for explanation of variable acronyms. For measurements of M. petersoni see Goodman et al. (2008).

except a ring of hairs around the lateral margin. The ear terminates with a slightly elongated and rounded tip anteriomedially. The average tragus length in the holotype and other animals referred to this taxon is 3.9 mm (range 3–4 mm) (table 3). The tragus is distinct, being a proximally broad and laterally short structure, and in some specimens with a pronounced lateral flange that becomes reduced distally. Toward the tip, which varies from being rounded to slightly pointed, the tragus tapers medially and has sparse and relatively long fur, which is not easily visible to the naked eye (fig. 4A–C).

The skull of M. brachytragos has a notably short rostrum, compared to the other diminutive Malagasy members of this genus, a slightly bulbous braincase, and not particularly constricted at the level of the interorbitals (fig. 5). In dorsal view, the rostrum is relatively linear in shape, particularly the nasals, which do not show a marked lateral expansion in their medial portions, and are about onehalf longer than the width. The central sulcus of the nasal is relatively deep and wide, spanning more than the proximal two-thirds of the nasal length. Frontals somewhat rounded. The sagittal crest is not prominent and terminates distally before the junction of the parietals. In lateral view, there is a flattening or depression in the parietal region. Lambdoid crest is developed, but not prominent. The palatal emargination forms a notably open and proximally rounded Vshaped or U-shaped notch. Medial portion of palate is slightly concave and the lingual portions of toothrows are aligned in parallel. The posterior palatal spine is relatively short and blunt (broken in holotype). In most individuals, including the holotype, there are distinct and rounded palatal foramina at the level of the last upper molar.

Dental formula I 2/3 C 1/1 PM 2/3 M 3/3, comprising the adult dentition of 36 teeth, and characteristic of Miniopterus ( Koopman, 1994) . The dentition of M. brachytragos is typical of small members of this genus, which includes a first premolar (PM2) that is relatively small and with a more simple cusp morphology than the second premolar (PM4). In lateral view, the length of PM4 is about two-thirds that of the C (fig. 5).

On the basis of t-test comparisons, two of the 19 measured measurement variables showed evidence of sexual dimorphism, including forearm length with the mean measurement in males of 36.0 mm and in females of 36.9 mm (P 5 0.02, df 5 27) and mass for which the mean measurement in males was 3.8 g and females 4.5 g. In the first case, this difference is considered biologically unimportant and, in the second case, several of the females were pregnant. Hence, in M. brachytragos sexual dimorphism is not notable and the sexes have been combined in the analyses presented herein.

Little variation was found in the craniodental morphology and measurements within the type series of M. brachytragos . Two exceptions are worth mentioning, both specimens possessing the characteristic tragus of this species: (1) FMNH 172867 from the Bemaraha is notably larger in cranial measurements than the other available specimens; a tissue sample was not available for this individual for the molecular portion of this study and (2) FMNH 175871 from the Namoroka has a flatter rostrum and more rounded frontals than typical of this species, but, based on the genetic analysis, this animal is clearly referable to M. brachytragos (fig. 2; table 1).

MORPHOLOGICAL AND MORPHOMETRIC COM- PARISONS: In the hand, M. brachytragos is immediately separable from other Miniopterus spp. known from the Malagasy region by its distinctive tragus, which is very short, stumplike structure (fig. 4A–C). In one of the illustrated tragi (fig. 4A) the distal tip is pointed, rather than rounded in the other individuals, and this maybe an anomalous condition in this species. Other characters to differentiate M. brachytragos from the different regional diminutive members of this genus are presented in the Comparisons section under the next species.

PHYLOGEOGRAPHY: Miniopterus brachytragos is characterized by an average intraclade divergence of average 0.7% K 2P. Most of the analyzed tissue samples come from Namoroka, for which one haplotype was shared among eight individuals, and animals from this locality showed a mean sequence divergence of 1.0%. The most distinctive haplotype (mean 2.1% divergence) was FMNH 188651, which came from Nosy Komba, a near-shore island separated from the main island by 5 km of water. In the same regard, a specimen from the Masoala Peninsula (FMNH 202523) differed by a mean divergence of 1.1% from the others. These apparent subclades might imply some phylogeographic structure in this taxon, but current sampling is insufficient to draw any clear conclusion.

ECOLOGICAL NOTES: The holotype and the associated paratypes from the same locality were captured in the limestone Namoroka Massif soon after dusk in a harp trap placed within slightly disturbed western dry forest and in close proximity to one of the entrances of the Grotte d’Ambovonomby. This portion of the massif has heavily eroded limestone karst, with deeply sculpted rock pinnacles, known as tsingy. Miniopterus brachytragos was also obtained at two other nearby sites in the Namoroka Massif, both gallery forests surrounded by anthropogenic savannah and with flowing water—the Ampandra River site was just outside the limit of the park and the Mandevy River site at a locality where an artesian water source percolates from the ground. The elevation range of M. brachytragos in the Namoroka region is from 100 to 200 m. The second limestone karst location where this species has been documented is in the Bemaraha Massif at 100 m elevation. Here a single individual was netted within a canyon in undisturbed tsingy forest just south of the Tombeau Vazimba and over a temporary water pool.

Miniopterus brachytragos has been recorded at three other sites with notably different habitats. In the Forêt de Binara, near the village of Daraina, in the central northeast, it was netted over the Analamazava River in a zone dominated by lowland humid forest with elements of western dry forest. Some exposed sedimentary rock occurs along the river with eroded crevices. This locality is at about 320 m elevation. The second site was on the offshore island of Nosy Komba, less than 5 km over water distance from the main island, in a mixed habitat composed of introduced mango ( Mangifera indica ) and western dry forest. The final locality, in the northeast on the Masoala Peninsula and just south of Ambanizana, was in disturbed gallery lowland Humid Forest within close distance to the sea.

ETYMOLOGY: The name is derived from the Greek brachys (‘‘short’’) and tragos, meaning ‘‘goat,’’ a word ultimately borrowed into New Latin to mean ‘‘tragus,’’ and has been chosen as this taxon is easily distinguished from its congeners by its diminutive tragus.

Figures

Fig. 3. Photograph of living Miniopterus brachytragos captured near Ambanizana, Masoala Peninsula

Fig. 4. Right ear and tragus of Miniopterus spp. from Madagascar: A, M. brachytragos (FMNH 175840, holotype), from Parc National de Namoroka, Forêt d’Ambovonomby, 26 km NW Andranomavo; B, M. brachytragos (FMNH 172685) from the Forêt de Binara, near Analamazava River, 7.5 km SW Daraina (village); C, M. brachytragos (FMNH 202523) from 1.8 km S Ambanizana, Masoala Peninsula; D, M. mahafaliensis (FMNH 173197, holotype) from Parc National de Tsimanampetsotsa, 6.5 km NE Efoetse, near Mitoho Cave; E, M. mahafaliensis (FMNH 176101) from Parc National de Kirindy-Mite, near village of Betakilotra, 11 km SE Marofihitsa; F, M. griveaudi (FMNH 184055) from Beloboka, grotte n°1, 12.5 km E Mahajanga, Madagascar; G, M. aelleni (FMNH 175842) from the Parc National de Namoroka, Forêt d’Ambovonomby, 26 km NW Andranomavo. The slightly elongated and pointed distal portion of the tragus in FMNH 175840 (A), as compared to FMNH 172685 and FMNH 202523, maybe an anomalous shape in M. brachytragos.

Fig. 5. Different views of skull and mandible of the holotype of Miniopterus brachytragos (FMNH 175840) collected in the Parc National de Namoroka, Forêt d’Ambovonomby, 26 km NW Andranomavo: (above, left) dorsal view of cranium; (above, right) ventral view of cranium; and (below) lateral view of cranium and mandible. (Photograph taken by John Weinstein, Field Museum image number Z94486_05d.)