Guianan Broad-nosed Bat Figures 4–7
P [latyrrhinus]. helleri: Lim, 1993: 162 (part)
Platyrrhinus helleri: Smith and Kerry, 1996: 932 (part) Platyrrhinus helleri: Lim and Engstrom, 2000: 121 P [latyrrhinus]. helleri: Lim and Engstrom, 2001 a: 632 (part) Platyrrhinus helleri: Lim and Engstrom, 2001 b: 664 (part) Platyrrhinus helleri: Engstrom and Lim, 2002: 364 (part) Platyrrhinus helleri: Lim and Norman, 2002: 54
P [latyrrhinus]. helleri: Lim et al., 2002: 1239 (part) Platyrrhinus helleri: Lim and Engstrom, 2005: 77 (part) Platyrrhinus helleri: Lim et al., 2005 a: 244 (part)
Platyrrhinus helleri: Lim et al., 2005 b: 87 (part)
Platyrrhinus helleri: Clare et al., 2007: 187 (part)
Platyrrhinus helleri: Borisenko et al., 2008: 475 (part) Platyrrhinus helleri: Lim, 2009: 45 (part)
P [latyrrhinus]. recifinus: Velazco, 2009: 259 (part) Platyrrhinus recifinus: Tavares and Velazco, 2010: 119 (part) Platyrrhinus helleri: Clare et al., 2011: 8 (part)
Platyrrhinus helleri: Clare, 2011: 4 (part)
Platyrrhinus helleri: Lim, 2012: 253 (part)
Platyrrhinus helleri: Lim and Tavares, 2012: 115 (part) Holotype. Dried skin, skull and skeleton of an adult pregnant female, Royal Ontario Museum (ROM) number 113465, obtained 20 September 2001 by Burton K. Lim and Zacharias Norman (original field number F 50445).
The skin, skull, and skeleton are in good condition. Frozen tissues are deposited at the Royal Ontario Museum (F 50445).
Type locality. Pobawau Creek mouth, 100 m; Upper Takutu-Upper Essequibo; Guyana, 3 ° 16 ’ 3.1 ”N, 58 ° 46 ’ 42.7 ”W (Fig. 3).
Paratypes. The skin, skull, and skeleton of an adult male (ROM 108487) caught on 8 October 1997 at 38 mi Camp, 35 km SW Kurupukari, 100 m, Iwokrama Forest, Potaro-Siparuni, Guyana, 4 ° 22 ’W, 58 ° 51 ’W; one skin and skull of an adult male (ROM 114070) caught on 16 April 2002 and one skin, skull, and skeleton of an adult pregnant female (ROM 113991) caught on 13 April 2002 at Brownsberg Nature Park headquarters, 500 m, Brokopondo, Suriname, 4 ° 57 ’N, 55 ° 11 ’W; and the skin and skull of an adult male (ROM 114195) caught on 21 April 2002 at Km 2.4 Wittie Kreek trail, 300 m, Brownsberg Nature Park, Brokopondo, Suriname, 4 ° 56 ’N, 55 ° 10 ’W. The holotype and 4 paratypes, along with 31 other specimens from the known distributional range, are listed in Appendix 1 (Fig. 3). Measurements of each specimen of the type series of P. guianensis are provided in Table 4.
Distribution. Platyrrhinus guianensis is known from Guyana and Suriname (Fig. 3).
Etymology. The species name is derived from the Latin description of its endemic distribution in the Guiana region of South America.
Diagnosis. Platyrrhinus guianensis is distinguished from its congeners by a combination of external and craniodental characteristics. The ventral fur is dark gray; ventral fur unicolor; dorsal stripe wide and brilliant white; fringe of hair along margin of uropatagium long, conspicuously dense, and pale yellow. The skull of P. guianensis lacks a fossa on the squamosal root of the zygomatic arch. Dentally, two stylar cuspules are present on the posterior cristid of P 4; and one stylid cuspulid on the anterior cristid of p 4.
Description. Platyrrhinus guianensis is a small Platyrrhinus (FA 37–41 mm) distinguished from its sister species P. recifinus by its smaller size and shorter skull (Table 5; Velazco & Gardner 2009, Table 2–4 and 7). However, measurements of P. guianensis overlap with P. angustirostris, P. brachycephalus, P. fusciventris, P. helleri, P. i n c a r u m, and P. matapalensis (Tables 4 –5). Dorsal fur mostly dark brown, but paler on the upper dorsum; dorsal fur is bicolored with darker tips; facial stripes wide and white; dorsal stripe brilliant white; ventral fur dark gray, individual hairs unicolored; pinnae have well-marked fold lines; tragus and anterior and posterior rims of pinnae bright yellow (Fig. 4); lateral borders of the proximal half of the noseleaf and borders of the horseshoe yellow; inferior border of the horseshoe completely free of upper lip; posterior margin of uropatagium has the shape of an inverted ‘U’; hair on upper surface of feet brown, long and dense (Fig. 5); fringe of hair along the trailing margin of uropatagium long, conspicuously dense, and pale yellow; metacarpal III longer than metacarpal V.
Rostrum is slender; has a well developed anterior notch in the nasals; postorbital processes moderately developed; paraoccipital processes poorly developed; two infraorbital foramina present; posterior border of hard palate ‘V’-shaped (Fig. 6); fossa on the squamosal root of the zygomatic arch absent; and paraoccipital and paracondylar processes poorly developed.
Upper inner incisors bilobed and convergent, not in contact, and tips extend below level of cingula of upper canines; upper outer incisors monolobate; two stylar cuspules on posterior cristid of P 4; hypoconal basin fossa of P 4 shallow; M 1 parastyle present; M 1 mesostyle absent; M 1 metacone divided in two cones; M 1 metacone labial cingulum present; stylar cuspule absent on lingual cingulum of M 1 metacone; sulcus on posterior cristid of paracone joined to cingulum of lingual face of metacone on M 1; M 1 metastyle present; M 1 protocone well developed; M 2 parastyle present; labial cingulum present on M 2 paracone; stylar cuspule on lingual face of M 2 paracone absent; M 2 metastyle present; stylar cuspule absent on lingual face of M 2 metacone; lingual cingulum of the M 2 metacone not extending to the paracone; developed M 2 hypoconal basin; M 3 minute; labial and lingual cingulids on p 4; one stylid cuspulid on anterior cristid of p 4; two stylid cuspulids on posterior cristid of p 4; m 1 paraconid poorly developed; labial and lingual cingulids present on m 1; stylid cuspulid present on anterior cristid of m 1 protoconid; m 1 metaconid well developed; m 2 hypoconid absent; stylid cuspulid between the metaconid and protoconid poorly developed on m 2; labial and lingual cingulids present on m 2.
Comparisons. Platyrrhinus guianensis can be confused with P. angustirostris, P. brachycephalus, P. fusciventris, P. he l l e r i, P. i nc a r u m, and P. matapalensis because their external and cranial measurements overlap (Table 3–4). But it can be easily distinguished from P. brachycephalus and P. matapalensis by the presence of one accessory cuspulid on the anterolingual cristid of p 4 (Fig. 7) (cuspulid lacking in P. matapalensis and two accessory cuspulids present in P. brachycephalus; Velazco 2005, fig. 27). Therefore, the following comparisons focus on differentiating P. guianensis from P. angustirostris, P. fusciventris, P. helleri, and P. incarum.
Externally, ventral fur is dark gray in P. guianensis and P. angustirostris (brownish gray in P. i n c ar u m; pale gray in P. h el l e r i; brown in P. fusciventris); ventral fur unicolored in P. guianensis, P. angustirostris, P. fusciventris, and P. h el l e r i (bicolored in P. i nc a r u m); dorsal stripe wide and brilliant white in P. guianensis and P. he l l e r i (conspicuous but narrow in P. angustirostris, P. fusciventris, and P. incarum); tragus and anterior and posterior rims of pinnae bright yellow in P. guianensis, P. fusciventris, and P. helleri (whitish in P. angustirostris and P. incarum); lateral borders of the proximal half of the noseleaf and borders of the horseshoe yellow in P. guianensis, P. fusciventris, and P. he l l e r i (whitish in P. angustirostris and P. i n c ar um); posterior margin of uropatagium with a shape of an inverted ‘U’ in P. guianensis, P. angustirostris, and P. i n c ar u m (‘V’ shaped in P. fusciventris and P. helleri); fringe of hair along margin of uropatagium long, conspicuously dense, and pale yellow in P. guianensis (long, dense, and pale brown in P. helleri; long, dense, and whitish in P. fusciventris and P. i nc a r u m; short, dense, and pale brown in P. angustirostris); hair on the upper surface of feet brown, long and dense in P. guianensis, P. angustirostris, and P. i n c a r um (short and intermediate in density in P. fusciventris and P. hell eri); metacarpal III longer than metacarpal V in P. guianensis, P. angustirostris, and P. i n c a r um (metacarpals III and V subequal in P. fusciventris and P. he l l e r i).
Cranially, there is a ‘V’-shaped posterior border of the hard palate in P. guianensis, P. angustirostris, P. hel leri, and P. i n c ar u m (‘V’- or ‘U’-shaped in P. fusciventris); fossa on the squamosal root of the zygomatic arch absent in P. guianensis, P. helleri, and P. i ncarum (shallow in P. angustirostris and P. fusciventris).
Dentally, there are two stylar cuspules on posterior cristid of P 4 in P. guianensis, P. fusciventris, P. helleri, and P. i nc a r u m (three in P. angustirostris); stylar cuspule on lingual face of M 2 paracone absent in P. guianensis, P. angustirostris, and P. fusciventris (one stylar cuspule in P. he l l e r i and P. incarum); M 3 minute in P. guianensis and P. i n ca r u m (larger in P. h el l e r i, P. angustirostris, and P. fusciventris); one stylid cuspulid on the anterior cristid of p 4 in P. guianensis, P. fusciventris, and P. helleri (one or two in P. i n ca r u m and P. angustirostris); tall m 2 protoconid in P. guianensis, P. angustirostris, P. fusciventris, P. i n c a r um (Fig. 7) (shorter in P. helleri); hypoconid lacking on m 2 in P. guianensis, P. angustirostris, P. fusciventris, and P. helleri (poorly developed in P. i n c a r um); poorly developed stylid cuspulid between the metaconid and protoconid on m 2 in P. guianensis, P. fusciventris, and P. helleri (well developed in P. i ncarum and P. angustirostris).
Natural history. Platyrrhinus guianensis has been documented from an elevational range of 60 to 500 m and is found primarily in rainforest (n= 33), but 3 individuals were netted in savanna. Of the 36 specimens examined, 16 are males and 20 females. Testes size (length by width in mm) ranged from 3 by 2 to 5 by 4. From 12 January to 9 February 2006, 8 of 10 females were pregnant with crown-rump (CR) measurements ranging from 4 to 13 mm. A female was pregnant on 13 April 2002 and another on 27 July 2009 with CR of 13 mm and 4 mm, respectively. Three females were pregnant on 20 and 21 September 2001 with CR ranging from 18 to 21 mm. A non-pregnant female was collected on 24 October 1997. A female had an embryo with CR of 26 mm collected on 31 October 2005. Two non-pregnant lactating females were caught on 8 and 11 November 1999 and one non-pregnant female was caught on 19 November 1997.