Artibeus aequatorialis Andersen, 1906

Larsen, Peter A., Marchán-Rivadeneira, María R. & Baker, Robert J., 2010, Taxonomic status of Andersen’s fruit-eating bat (Artibeus jamaicensis aequatorialis) and revised classification of Artibeus (Chiroptera: Phyllostomidae), Zootaxa 2648, pp. 45-60 : 51-55

Artibeus aequatorialis Andersen, 1906

Andersen’s Fruit-eating Bat

Artibeus jamaicensis aequatorialis Andersen, 1906

Artibeus jamaicensis aequatorialis Andersen, 1908

A [rtibeus]. l [ituratus]. aequatorialis: Hershkovitz, 1949: 447 ; name combination.

Holotype. BMNH 0.2.9.13: adult male, skin and skull; collected by Perry O. Simons, no. 395, 17 June 1899. Type locality. Ecuador: Department of El Oro, Zaruma; 1000m.

Distribution. West of the Andes Mountains from northern Peru, northward throughout western Ecuador to Colombia ( Fig. 3 ). The northernmost and southernmost distribution of A. aequatorialis in Colombia and Peru, respectively, is unknown. Elevation ranges from 22m ( Ecuador: Guayas) to 1,106m ( Ecuador: El Oro). This species seems to exploit a variety of habitats, ranging from the dry forests of northern Peru and southern Ecuador to the tropical forests of the Chocó in Colombia. Occurs sympatrically with Artibeus fraterculus and/ or A. lituratus throughout most of its distribution.

Genus Artibeus Leach, 1821

Artibeus aequatorialis Andersen, 1906

A. amplus Handley, 1987

A. concolor Peters, 1865

A. fimbriatus Gray, 1838

A. fraterculus Anthony, 1924

A. hirsutus Andersen, 1906

A. inopinatus Davis and Carter, 1964

A. jamaicensis Leach, 1821

A. j. jamaicensis Leach, 1821 A. j. parvipes Rehn, 1902 A. j. paulus Davis, 1970

A. j. richardsoni Allen, 1908 A. j. triomylus Handley, 1966 A. j. yucatanicus Andersen, 1908

A. lituratus ( Olfers, 1818)

A. l. intermedius Allen, 1897 A. l. koopmani Wilson, 1991 A. l. lituratus Olfers, 1818 A. l. palmarum Allen and Chapman, 1897

A. obscurus ( Schinz, 1821)

A. planirostris Spix, 1823

A. p. fallax Peters, 1865

A. p. grenadensis Andersen, 1906 A. p. hercules Rehn, 1902 A. p. trinitatus Andersen, 1906

A. schwartzi * Jones, 1978

Specimens examined. (n = 79) (* indicates specimen used in molecular analyses). Ecuador: Azuay, Manta Real Manglar (2°33'60"S, 79°21'20"W), 1 Ψ (MEPN 913072); Bolivar, Barraganate (1°27'20"S, 79°19'60"W), 1 ɗ, 1 Ψ (MEPN 80412, 80460); Carchi, El Pailon (1°0'7"N, 78°14'11"W), 1 ɗ, 2 Ψ (MEPN 871842, 871752, 871850); El Oro, Bosque Petrificado Puyango (3°53'3"S, 80°4'41"W), 2 Ψ (TTU 102596, 103794 [TK 135290*]), El Progreso (3°19'60"S, 79°49'0"W), 2 ɗ, 3 Ψ (QCAZ 2111, 2113, 2109, 2116–17), 9 mi S Zaruma (3°40'60"S, 79°37'0"W), 1 ɗ (TCWC 12283), El Faique (3°42'7"S, 79°37'18"W), 1 Ψ (TTU 102771 [TK 135391*]); Esmeraldas, Borbon comuna Corriente Grande (0°30'0"N, 79°58'0"W), 2 ɗ (QCAZ 2150, 2154), Borbon comuna Viruela (1°6'51"N, 78°59'37"W), 1 ɗ, 3 Ψ (QCAZ 2168, 2173, 2178, 2181), Casa Comunal Mataje (1°12'4"N, 78°33'42"W), 1 Ψ (MEPN 882048), Chontaduro (0°55'60"N, 79°23'16"W), 1 ɗ (MEPN 851433), Comunidad Valle del Sade (0°31'0"N, 79°22'0"W), 1 ɗ, 1 Ψ (MEPN 85932, 85971), E San Lorenzo, Banana Plantation (1°9'11"N, 78°27'54"W), 2 Ψ (TTU 85369–70), Esmeraldas (0°58'60"N, 79°39'20"W), 1 ɗ, 2 Ψ (QCAZ 2479, 2466, 2484), Estacion Experimental La Chiquita (1°13'55"N, 78°45'57"W), 5 Ψ (TTU 85284; QCAZ 2344, 2376–77, 2380), Finca in the road from Lita to San Lorenzo (1°5'16"N, 78°41'29"W), 1 ɗ (TTU 103068), Mataje (1°21'21"N, 78°43'27"W), 2 ɗ, 2 Ψ (TTU 103109 –10 [TK 135905*–TK 135906*], 103107, 103196), near to Quingue (0°43'0"N, 80°4'60"W), 1 ɗ, 1 Ψ (QCAZ 6070, 6072), Quininde, Rio Sade (0°19'60"N, 79°28'0"W), 1 Ψ (MEPN 85996), Rio Verde (1°4'0"N, 79°25'0"W), 1 ɗ, 1 Ψ (MEPN 851431, 851436), San Francisco de Bogota (1°4'21"N, 78°42'41"W), 2 ɗ (TTU 103180 –81 [TK 135701*–TK 135702*]), San Lorenzo, la Guarapera banana farm pasture (1°9'41"N, 78°28'52"W), 2 ɗ, 3 Ψ (TTU 85409, 85417–19, 85370), Zapallo Grande (0°46'60"N, 78°58'60"W), 1 Ψ (QCAZ 67); Guayas, El Triunfo (2°19'0"S, 80°24'0"W), 1 ɗ, 1 Ψ (QCAZ 2609, 2607), Manglares Churute (2°27'17"S, 79°37'39"W), 3 ɗ, 2 Ψ (TTU 103689, 103692 [TK 134602*], 103712, 103696, 103697), Naranjal, 7 mi N of Bucay (1°30'0"S, 79°54'0"W), 1 ɗ (AMNH 62934), La Union (1°58'0"S, 80°1'0"W), 4 ɗ, 2 Ψ (QCAZ 2050–51, 2055–56, 2049, 2054); Loja, 15 mi N Catacocha (4°4'0"S, 79°37'60"W), 1 ɗ (TCWC 12282); Los Rios, Buena Fe (0°54'0"S, 79°28'60"W), 1 ɗ (MEPN 81312); Manabi, Cauque River, El Destino (0°0'0"N, 80°5'60"W), 1 ɗ (AMNH 64547), Cerro Pata de Pajaro (0°1'60"N, 79°58'0"W), 1 ɗ (MEPN 913112), Parque Nacional Machalilla (1°31'0"S, 80°42'0"W), 1 Ψ, 1 ɗ (MEPN 964794, 902898), Pedernales (0°4'60"N, 80°2'60"W), 1 Ψ, (MEPN 913113); Pichincha, Bosque Protector La Perla (0°0'0"N, 79°22'60"W), 2 ɗ, 1 Ψ (QCAZ 61, 427, 399), Nanegal (0°10'10"N, 78°40'5"W), 1 Ψ (QCAZ 1998), Santa Rosa, Rio Toachi (0°19'0"S, 78°57'0"W), 1 Ψ (QCAZ 4236), Union del Rio Toachi, Otongachi (0°25'0"S, 79°0'0"W), 1 ɗ (QCAZ 4711).

Emended diagnosis. Compared with A. jamaicensis , A. aequatorialis has a larger, broader, and more robust skull and dentition. In skull size proportion A. j. richardsoni is most similar to A. aequatorialis , while the subspecies A. j. paulus is the smallest form within A. jamaicensis followed by increased size in A. j. parvipes, A. j. yucatanicus, and A. j. jamaicensis . Nasals are moderately tubular in both A. jamaicensis and A. aequatorialis , with the orbitonasal shield being concave ( Patten 1971). The pre- and post-orbital ridges and processes are poorly developed in A. aequatorialis , with a less arched and broader appearance of the rostrum with respect to A. jamaicensis . The zygomatic arch is more slender in A. jamaicensis . A higher coronoid process and longer distance from the condyle to the coronoid process is present in A. aequatorialis with respect with A. jamaicensis , and the angular process is relatively small in both taxa. Dentition is proportional to the skull size, being more robust in A. aequatorialis . Protocone and hypocone of the first upper molar (M1) are moderately well developed, with a wider talon in A. aequatorialis . In A. aequatorialis and A. jamaicensis , the second upper molar (M2) is distinctly more reduced in size and shape with paracone expanded and a developed labial cingulum ( Patten 1971). Metacone and metaconule of M2 form a distinct lobe in both species. M1 and M2 are separated by a bigger gap in A. aequatorialis . The third lower molar (m3) is reduced in size (when present, see below) and does not show well developed cusps in either A. aequatorialis or A. jamaicensis . The dental formula in both A. aequatorialis and A. jamaicensis is I 2 /2, C 1/1, P 2/2, M 2/2–3, total 30–32. Of the 134 specimens examined, A. aequatorialis and A. jamaicensis presented two upper molars and few specimens were missing the m 3 in one or both sides of the mandible. Externally, A. aequatorialis and A. jamaicensis are very similar with major differences in body size proportions. For both species, the color of fur varies from pale to dark brown, with lighter color of the ventrum. Both species are characterized by a black patagium and uropatagium ( Patten 1971). Artibeus aequatorialis has been characterized by white wing tips ( Patten 1971), however, this characteristic is variable and is also present in A. jamaicensis . Facial stripes are not well defined in A. aequatorialis and are variable in A. jamaicensis .

Two congeneric species, A. fraterculus and A. lituratus , occur in sympatry with A. aequatorialis . In body and skull size, A. aequatorialis is intermediate between A. lituratus and A. fraterculus . Artibeus fraterculus is paler than A. aequatorialis and is known only from the Pacific slope of central-southern Ecuador and northern Peru. Nasals are not tubular, M2 is close to M1, and metacone and metaconule are not set apart from the teeth in A. fraterculus as in A. aequatorialis ( Patten 1971) . Artibeus lituratus differs mostly from A. aequatorialis in having a more robust, larger, and wider skull and dentition, with distinct supraorbital stripes and brownish fur ( Jones 1978). The pre- and post-orbital constriction is narrower in A. lituratus , with the optic spicules extended.

There has been a historical debate about the recognition of A. planirostris as a morphologically and genetically defined species distributed east of the Andes in South America (see Larsen et al. 2007). With respect to body and skull size proportion, Artibeus aequatorialis is smaller than A. planirostris , and the former differs from A. planirostris in skull and dentition mainly by: shape of the zygomatic arch (slender = A. aequatorialis ; robust = A. planirostris ); development of paracone when compared to metacone of M1 (metacone bigger than paracone = A. aequatorialis ; metacone smaller than paracone = A. planirostris ); location of M1 with respect to M2 (M1 and M2 separated by a large gap = A. aequatorialis ; M1 and M2 without substantial gap = A. planirostris ); and metacone and metaconule of the M2 (metacone and metaconule separated as a distinct lobe from rest of M2 by a fissure = A. aequatorialis ; metacone and metaconule not separated as a distinct lobe from the rest of M2 = A. planirostris ).

Measurements. Artibeus aequatorialis is larger than A. jamaicensis in all fourteen cranial and mandibular measurements, and is generally intermediate between A. fraterculus and A. lituratus (Appendix II).

Figures

FIGURE 3. Map of the distribution of Artibeus aequatorialis. Star indicates the type locality of A. aequatorialis (Zaruma [3 ° 40 ' 60 " S, 79 ° 37 ' 0 " W], Ecuador). The distributional range is based on literature references (hollow squares; Andersen 1906 and Marques-Aguiar 2008) and specimens examined in the Species Account (star and solid squares). The northernmost (western Colombia; Valle del Cauca, Cali [3 ° 26 ' 14 " N, 76 ° 31 ' 21 " W], and Rio Raposo [3 ° 43 ' 0 " N, 77 ° 7 ' 60 " W]) and southernmost (western Peru; Tumbes, Faical [3 ° 44 ' 57 " S, 80 ° 45 ' 2 " W]) extent of A. aequatorialis remains to be defined. Shaded areas represent areas of the Andes Mountains higher than 1800 meters.