Sexual dimorphism in the endangered Florida bonneted bat, Eumops floridanus (Chiroptera: Molossidae)

Abstract

Interest in the Florida bonneted bat (Eumops floridanus) has risen dramatically since the species was listed as federally endangered in 2013. However, understanding of many aspects of the species’ biology is limited, due in part to the fairly recent recognition of E. floridanus as a distinct species rather than a subspecies of E. glaucinus. Through a two-year mark-recapture study of E. floridanus roosting in a group of bat houses, we obtained morphological measurements on .200 individuals. We documented modest male-biased sexual size dimorphism (forearm length, wing width, and wing length were larger in adult males than adult females) and found gular glands exclusively among males. If these morphological differences lead to niche partitioning between sexes, conservation planning may need to consider the foraging habitat use of males and females independently. Relative to other species in the genus Eumops, E. floridanus had a moderate aspect ratio index, low wing shape index, and low wing tip index, suggesting the species may not be capable of flying at speeds as fast as other closely related species, but may be more maneuverable and more efficient when flying in cluttered space.

Full text

Biological Sciences
Sexual dimorphism in the endangered Florida bonneted bat, Eumops
floridanus (Chiroptera: Molossidae)
Holly K. Ober
(1)
, Elizabeth C. Braun de Torrez
(2)
, Robert A. McCleery
(2)
,
Amanda M. Bailey
(2)
, Jeffery A. Gore
(3)
(1)
Department of Wildlife Ecology and Conservation, University of Florida, 155 Research Road,
Quincy, FL 32351 USA
(2)
Department of Wildlife Ecology and Conservation, University of Florida, P.O. Box 110430,
Gainesville, FL 32611 USA
(3)
Florida Fish and Wildlife Conservation Commission, 3911 Hwy 2321, Panama City, FL 32409
USA
Abstract Interest in the Florida bonneted bat (Eumops floridanus) has risen dramatically since the
species was listed as federally endangered in 2013. However, understanding of many aspects of the
species’ biology is limited, due in part to the fairly recent recognition of E. floridanus as a distinct
species rather than a subspecies of E. glaucinus. Through a two-year mark-recapture study of E.
floridanus roosting in a group of bat houses, we obtained morphological measurements on .200
individuals. We documented modest male-biased sexual size dimorphism (forearm length, wing
width, and wing length were larger in adult males than adult females) and found gular glands
exclusively among males. If these morphological differences lead to niche partitioning between
sexes, conservation planning may need to consider the foraging habitat use of males and females
independently. Relative to other species in the genus Eumops,E. floridanus had a moderate aspect
ratio index, low wing shape index, and low wing tip index, suggesting the species may not be capable
of flying at speeds as fast as other closely related species, but may be more maneuverable and more
efficient when flying in cluttered space.
Keywords: Body condition, Eumops floridanus, Florida bonneted bat, morphology, sexual
dimorphism, wing shape
Introduction
The Florida bonneted bat (Eumops floridanus) is a rare species endemic to South
Florida, designated as federally endangered in 2013 (USFWS 2013). Eumops
floridanus is one of only eight species of the family Molossidae (free-tailed bats;
Norberg and Rayner 1987) found within the United States, and the only with
federal conservation status. Due to its rarity, small geographic range, and fairly
recent recognition as a distinct species (Timm and Genoways 2004), extremely
little is known about the basic biology of E. floridanus. A single species, E.
glaucinus, was previously believed to range across the northern one-third of South
America, Central America, Jamaica, Cuba, and south Florida (Barbour and Davis
1969). In recognition of significant morphological differences, Eumops occurring in
Corresponding author: Holly Ober, holly.ober@ufl.edu
38

Florida were designated a distinct subspecies in 1971 (E. g. floridanus; Koopman
1971), and then a distinct species in 2004 (E. floridanus; Timm and Genoways
2004). The recent classification of E. floridanus as an endangered species greatly
increases the need to understand its ecology (FWC 2011, USFWS 2013).
Establishment of baseline morphological data for E. floridanus is needed to
provide a foundation for future comparative studies and for developing appropriate
conservation strategies.
Although male-biased sexual dimorphism in body mass or size is relatively
common among many species of mammals (i.e., males are heavier or larger than
females; Isaac 2005), female-biased sexual dimorphism tends to be more pervasive
within Chiroptera (Ralls 1977, Williams and Findley 1979). For example, female-
biased sexual dimorphism is widespread among many species in the family
Vespertilionidae (Myers 1978, Williams and Findley 1979), particularly in forearm
length (Stevens and Platt 2015). In contrast, Molossidae commonly exhibit male-
biased sexual dimorphism (Freeman 1981). Male-biased sexual dimorphism has
been reported in several species of Eumops (Eger 1977), with more pronounced
differences in larger species within the genus. Eumops floridanus is intermediate in
overall size among these species, and the occurrence of sexual dimorphism in E.
floridanus is uncertain. The few studies that have investigated sexual dimorphism in
the closely related E. glaucinus have reached mixed conclusions regarding
dimorphism in mass and forearm length (Gardner et al. 1970, Eger 1977, Silva
Taboada 1979, Myers and Wetzel 1983, Bowles et al. 1990). Understanding
patterns of sexual dimorphism can be critical to development of species-specific
conservation strategies if differences in morphology result in differential habitat
selection or movement patterns between sexes (Blanckenhorn 2005, Isaac 2005).
Wing morphology is the primary determinant of flight capabilities of bats,
affecting foraging strategies, extent of foraging area, and migratory capacity
(Fenton 1972, Findley et al. 1972, Norberg 1972). Wing shapes vary among species
and also between sexes within species, resulting in differential habitat selection,
movement patterns, time budgets, diet, thermoregulatory requirements, metabolic
rates, and susceptibility to predation (Ralls 1977, Blanckenhorn 2005, Isaac 2005).
Wing length, wing tip length, aspect ratio, and speed are high among species in
Molossidae (Findley et al. 1972), whereas wing area is relatively small (Norberg
and Rayner 1987). Bats with long, narrow wings generally have rapid, efficient
flight, whereas bats with short broad wings have high turning performance (i.e.,
high maneuverability, meaning a small minimum space is required to change flight
directions at a given speed, and high agility, meaning a turn can be initiated at a
rapid rate; Findley et al. 1972, Norberg 1972). Molossids use swift, direct flight
trajectories to pursue prey through aerial hawking in open habitats or at high
altitudes, and to fly long distances when commuting between roosts and foraging
areas or migrating (Findley et al. 1972, Freeman 1981, Aldridge and Rautenbach
1987, Norberg and Rayner 1987). High metabolic costs are incurred when these
bats attempt to fly at slower speeds in confined spaces relative to faster speeds in
straight flight, which may constrain many molossids to forage exclusively in open
environments (Voigt and Holderied 2012). Gradation in flight capabilities among
Dimorphism in Eumops floridanus Ober et al.
Florida Scientist 80(1) 2017 QFlorida Academy of Sciences 39

species within Molossidae can be predicted on the basis of wing morphology
(Freeman 1981). To date, few live E. floridanus individuals have been captured,
and morphological measurements of E. floridanus specimens are extremely scarce.
Nothing is known about sexual dimorphism in wing morphology, or about wing
shape relative to that of closely-related species, constraining our understanding of
flight capabilities of these bats.
Due to a lack of data on basic morphology and flight capacity in E. floridanus,
our goal was to obtain a robust dataset of morphological measurements that would
enable interspecific and intraspecific comparisons. Given the presence of male-
biased sexual dimorphism in other Eumops and the ecological implications of
variation in wing morphology, our objectives were to compare mass, size, body
condition and wing morphology in E. floridanus of different sexes and ages, and
contrast wing morphology with that of other Eumops species.
Materials and Methods
We conducted this study at Fred C. Babcock - Cecil M. Webb Wildlife Management Area (BWWMA) in
southwest Florida. The vegetation communities were a mix of mesic and hydric pine flatwoods with
embedded freshwater marshes, ponds, and hardwood hammocks. Average annual temperature was
23.48C, and average rainfall was 128.8 cm per year, most of which fell during summer months (http://
www.usclimatedata.com). BWWMA was owned and managed by the Florida Fish and Wildlife
Conservation Commission (FWC).
Eumops floridanus was observed in Punta Gorda, FL (5 km from BWWMA) in 1979 (Belwood
1981), and was first detected on BWWMA in 2006. To augment roosting habitat for the species, the
FWC erected matched pairs of one- or three-chamber bat houses on poles at eight sites in 2007-2008, and
at five additional sites in 2012. Each pair of bat houses sharing a pole is considered a single roost. To
date, E. floridanus have been observed in nine of these 13 roosts.
We conducted seven multi-day capture sessions spaced four months apart: 22-25 April 2014, 27-30
August 2014, 15-17 December 2014, 20-24 April 2015, 24-26 August 2015, 14-16 December 2015, and
19-21 April 2016. During each session, we used triple-high mist nets in an attempt to catch every E.
floridanus roosting in each of the occupied roosts. Mist nets were opened at sunset and remained open for
a maximum of three hours.
Each captured bat was placed individually in a numbered cotton bag, and examined to determine
age (adult/sub-adult), sex, body mass, forearm length, reproductive status, and the presence or absence of
gular-thoracic glands. Sub-adults were distinguished from adults by examining the degree of fusion of
phalangeal cartilage; when that was ambiguous, we used status of genitals and mammae as secondary
indicators of age. Adult females were classified as non-reproductive, pregnant, lactating, or post-
lactating. Adult males were classified as non-reproductive (testes abdominal) or reproductive (testes
descended). We calculated body condition index (BCI ¼mass/forearm length; Reynolds et al. 2009,
Jonasson and Willis 2011, Lis´
on et al. 2014) to generate a relative metric of each bat’s overall condition
and to facilitate future comparisons of mass relative to body size when making inferences about wing
loading and fat reserves among individuals of different ages, sexes, and reproductive status.
During the December 2015 and April 2016 capture sessions, we took four additional wing
measurements from a subset of individuals. We fully extended the right wing of each bat and measured
the following lengths using dial calipers (precision 60.1mm): the distance from the wrist to the tip of
the 5
th
finger excluding the wrist (D5), distance from the wrist to the tip of the 3
rd
finger excluding the
wrist (D3), and length of the 1
st
and 2
nd
phalanx of the 4
th
finger (Figure 1). These are considered simple
descriptions of wing width (D5), wing length (D3), and wingtip width (1
st
and 2
nd
phalanx of the 4
th
finger; features that vary greatly in length among Molossidae; Freeman 1981). Each measurement was
repeated three times by the same observer and averaged. From these measurements we calculated three
indices: aspect ratio index ([D3þforearm]/D5; Findley et al. 1972), wing shape index (D3/D5; Fenton
Ober et al. Dimorphism in Eumops floridanus
40 Florida Scientist 80(1) 2017 QFlorida Academy of Sciences

1972), and tip index (100*D3/[D3þforearm]; adapted by Freeman 1981), to facilitate comparisons with
wing shapes of other Eumops species.
All bats were uniquely marked with passive integrated transponders (PIT-tag; 12 mm, 134.2 kHz
FDXB tags (Biomark Inc., Boise, ID)) to enable identification of recaptured individuals. Tags were
implanted subcutaneously in the lower lumbar region near the plagiopatagium. After processing, each bat
was released near the site of capture. All capture and handling processes followed American Society of
Mammalogists guidelines (Sikes et al. 2011), were approved by the University of Florida IACUC
(#201308070 and 201408587), and were in accordance with U.S. Fish and Wildlife Service permit #TE
23583B-1 and Florida Fish and Wildlife Conservation Commission permit #SUO-49616.
After examining all data to determine whether assumptions of normality and homogeneity of
variance were met with Shapiro-Wilks and Levene’s tests, we tested for differences in morphometric
measurements between sexes (mass and forearm length) using student’s t-tests (when data met
assumptions of normality and homogeneity of variance), Welch’s t-tests (when data had unequal
variance), or Mann-Whitney U tests (when data were not normally distributed). We tested for differences
in wing metrics (D5, D3, 1
st
and 2
nd
phalanx of the 4
th
finger) using MANOVA. Lastly, we compared
measurements among individuals of different reproductive status categories using ANOVA followed by
Tukey HSD tests for multiple comparisons. For all morphometric comparisons involving individuals
captured more than once, we used a single mean value to represent each characteristic for each individual
that was reported in the same reproductive category during more than one capture session. Throughout,
we define sexual size dimorphism as any statistically significant difference in morphometric
measurements of different sexes within the same age or reproductive category (Lovich and Gibbons
1992). All statistical analyses were conducted with SPSS version 23.0 (IBM Corp. 2015).
Results
During each of the seven capture sessions we captured 50, 61, 42, 56, 63, 79, and 89
individual Eumops floridanus respectively. In total we captured 201 unique
individuals: 36% were males and 64% were females. Gular glands were apparent on
all adult males and most sub-adult males, but absent from all females of both age
groups.
Mass ranged greatly among individuals (from 27 to 59 g), but we did not find
sexual dimorphism in mass (Table 1). Mass of all adult males (n¼65) did not differ
from mass of adult females that were not pregnant (i.e., non-reproductive or post-
lactating, n¼109) (t
172
¼0.090, p¼0.928). Similarly, mass of non-reproductively
Figure 1. Diagram showing measurements used to reflect Eumops floridanus wing size and shape.
Dimorphism in Eumops floridanus Ober et al.
Florida Scientist 80(1) 2017 QFlorida Academy of Sciences 41

active adult males (n¼16) did not differ from mass of non-reproductively active
adult females (n¼50) (t
18.26
¼0.137, p¼0.893).
We detected male-biased sexual dimorphism in forearm length, a characteristic
typically used to reflect overall body size in bats (Table 1). Forearm length ranged
from 60.0 to 69.1 mm. Forearm length of all adult males (¯
x¼63.74 61.44 mm, n¼
54) was significantly greater than that of all adult females (¯
x¼62.74 61.23 mm, n
¼111) (t
163
¼4.642, p,0.001). Similarly, forearm length of sub-adult males
(median ¼63.3 mm, n¼35) was significantly greater than that of sub-adult females
(median ¼62.5 mm, n¼35) (U ¼374.5, p¼0.005).
We found differences between adult males (n¼29) and females (n¼38) in
wing morphology (F
4,62
¼4.07, p¼0.005, Wilk’s K¼0.792, partial n
2
¼0.208).
Two of the four wing measurements differed between sexes, after Bonferroni
corrections to account for multiple comparisons (Table 2). Wing width (D5) was
greater in males than females (F
1,65
¼45.32, p,0.005; ¯
xdifference ¼1.56 mm,
95% CI from 0.76 to 2.35 mm larger). Wing length (D3) was also greater in males
than females (F
1,65
¼8.447, p¼0.005; ¯
xdifference ¼2.09 mm, 95% CI from 0.65
to 3.52 mm larger). In contrast, there were no differences in wingtip width (1st and
2
nd
phalanx of the 4th finger). Length of the first phalanx was similar in males and
females (F
1,65
¼4.1, p¼0.047; ¯
xdifference ¼0.44 mm, 95% CI from 0.01 to
0.87mm larger), as was length of the 2
nd
phalanx (F
1,65
¼0.007, p¼0.936; ¯
x
difference ¼0.01 mm, 95% CI from 0.02 mm smaller to 0.23 mm larger).
Body condition index (BCI) ranged from 0.460 to 0.952 (Table 1, Figure 2). We
found differences in BCI among bats of different reproductive categories [F
6, 274
¼
40.238, p,0.001]. There were no significant differences in BCI for post-hoc pair-
wise comparisons between male sub-adults, female sub-adults, male non-reproduc-
tive adults, and female non-reproductive adults; however, there were significant
differences in BCI for pair-wise comparisons between these categories and BCI of
reproductively active adult males, post-lactating females, and pregnant females.
Relative to seven other species in the genus Eumops,E. floridanus wing
morphology was typical in some respects but unusual in others. Eumops floridanus
had a moderate aspect ratio index, the second lowest wing shape index, and the
lowest tip index (Table 2).
Table 1. Mean (6SD) mass, forearm length, and body condition index (BCI; mass/forearm length) of
201 Eumops floridanus at Fred C. Babcock - Cecil M. Webb Wildlife Management Area, FL. Total
sample size exceeds the number of unique individuals captured because some individuals captured
multiple times exhibited different reproductive status during different capture events.
Sex Status nMass (g) Forearm (mm) BCI
Male reproductively active adult 31 43.77 64.38 63.72 61.49 0.686 60.062
non-reproductive adult 16 40.68 65.79 63.37 61.80 0.642 60.088
non-reproductive sub-adult 35 38.46 63.82 63.19 61.81 0.608 60.053
Female pregnant adult 56 47.13 64.10 62.75 61.30 0.750 60.063
post-lactating adult 59 45.29 62.96 62.79 61.26 0.722 60.046
non-reproductive adult 46 40.47 63.32 62.70 61.23 0.645 60.053
non-reproductive sub-adult 35 38.03 64.03 62.39 61.26 0.609 60.059
Ober et al. Dimorphism in Eumops floridanus
42 Florida Scientist 80(1) 2017 QFlorida Academy of Sciences

Table 2. Comparisons of selected wing characteristics among Eumops floridanus (mean 6SD, derived from this study) and those reported for other species in the genus
Eumops (from Freeman 1981).
Species nD3 D5 1
st
Phalanx of D4 2
nd
Phalanx of D4 Aspect Ratio Index Wing Shape Index Tip Index
E. floridanus 67 112.5663.07 61.1361.78 21.7960.90 5.0060.45 2.8860.06 1.8460.04 63.9660.46
(adult females) 38 111.6562.92 60.4661.67 21.6060.95 5.0160.49 2.8960.07 1.8560.04 63.9860.43
(adult males) 29 113.7362.89 62.0261.54 22.0460.79 5.0060.41 2.8760.05 1.8360.03 63.9460.51
E. auripendulus . . . . 3.04 2.05 67.43
E. bonariensis . . . . 2.70 1.81 66.90
E. glaucinus . . . . 2.94 1.95 66.43
E. hansae . . . . 3.01 1.96 65.11
E. maurus . . . . 2.93 1.95 66.54
E. perotis . . . . 2.88 1.92 68.41
E. underwoodi . . . . 2.87 1.95 67.79
Dimorphism in Eumops floridanus Ober et al.
Florida Scientist 80(1) 2017 QFlorida Academy of Sciences 43

Discussion
We found modest male-biased sexual dimorphism in Eumops floridanus. Forearm
length (often used as a surrogate for overall body size in bats) was larger for males
than females, in both adults and sub-adults. In addition, two of the four measures of
wing structure were larger in adult males than females, suggesting that wings of
males are both longer and wider than those of females. The degree of difference we
observed in forearm length between sexes was 1.5%, which is similar to the degree
of sexual dimorphism found in other bat species (Williams and Findley 1979,
Lindenfors et al. 2007, Lu et al. 2014, Wu et al. 2014).
We are aware of little previous investigation into the occurrence of sexual
dimorphism in E. floridanus. Only two publications report data on forearm length
of E. floridanus. Eger (1977) describes only males and does not speculate on sexual
dimorphism. Timm and Genoways (2004) reported greater average forearm lengths
than we found, 63.9 mm for males (n¼23), and 64.7 mm for females (n¼4), and
concluded that the species was not sexually dimorphic. The differences between
our findings and those of Timm and Genoways (2004) may be because: 1) we
measured live specimens while they measured preserved museum specimens,
which can produce discrepancies (Bininda-Emonds and Russell 1994, Simmons
and Voss 2009, Stephens et al. 2015), 2) their sample size was not large enough to
accurately capture the variation in forearm length within and between sexes, and/or
Figure 2. Mean 6SE in body condition index (BCI) among Eumops floridanus of different sexes and
reproductive categories.
Ober et al. Dimorphism in Eumops floridanus
44 Florida Scientist 80(1) 2017 QFlorida Academy of Sciences

3) their small sample size resulted in analyses that lacked adequate power to detect
differences between sexes. Regardless, potential differences in measurements from
live and preserved specimens do not influence the comparisons between sexes we
report, as all our measurements were on live animals.
Sexual dimorphism is often explained by sexual selection. It has been argued
that sexual selection in males is the primary evolutionary force selecting for larger
body size (Ralls 1977, Blanckenhorn 2005). Further, it is common for males to be
slightly larger in size than females among mammal species that have a harem social
structure due in part to male - male competition (Racey 2009). There is evidence
that E. floridanus use a harem social structure (Ober et al. 2016) and our finding of
gular glands in males but not females provides additional evidence to support the
potential role of sexual selection. These glands are present in several species of
Molossids (Horst 1966, Gutierrez and Aoki 1973, Gustin and McCracken 1987,
Scully et al. 2000), and had been noted previously for Eumops in general (Eger
1977), and more specifically in E. glaucinus (Silva Taboada 1979, Bowles et al.
1990) and E. floridanus (Belwood 1992). In most species these gular glands are
well developed in males and rudimentary or lacking in females (Horst 1966, Scully
et al. 2000), as we found in the present study. In other species, these glands undergo
seasonal fluctuations in size, becoming swollen with sebaceous oils during breeding
seasons (Gutierrez and Aoki 1973, Krutzsch 2000), but understanding of their exact
function is limited. It has been proposed that these glands may be used in harem
defense and roost site marking (Belwood 1992).
Sexual size dimorphism may result in sex-specific niche utilization (Selander
1966, Williams and Findley 1979). Individuals with high wing loadings (defined as
body mass/wing area) tend to have fast flight speeds but low maneuverability
(Aldridge and Rautenbach 1987, Norberg and Rayner 1987). The larger wing size
of adult males relative to females results in lower wing loading for males, which
may slightly lessen niche overlap during the energetically demanding phase of
pregnancy. As the only species known to form harems in the U.S., niche
differentiation may be especially important for E. floridanus because individuals
are not sexually segregated during the maternity season, as is the case with the
majority of temperate species (Bradbury 1977, Senior et al. 2005). Future
investigations of whether males and females forage in different habitats or at
different distances from roosts would better inform recovery plans for the species.
The two better-known Eumops species that occur in the U.S. (E. perotis and E.
underwoodi) are considered to be among the fastest flying species in the country.
(Vaughan 1966, Findley et al. 1972). Eumops perotis and E. underwoodi are found
in dry regions at high elevation in the western U.S., Mexico, and Central and South
America where they forage in open habitat. They roost in shallow caves and
crevices in cliffs and rock walls that provide a substantial vertical drop to enable
launch into flight after roosting (Kiser 1995, Best et al. 1996), as well as in cavities
in tall plants with minimal foliage to impede the bats’ approach (i.e., royal palms
(Roystonea; Hellebuyck et al. 1985) and saguaro cacti (Carnegia gigantea; Tibbitts
et al. 2002). Our results indicate that although E. floridanus has an aspect ratio
index similar to these species, it has a lower wing shape index (the second lowest
Dimorphism in Eumops floridanus Ober et al.
Florida Scientist 80(1) 2017 QFlorida Academy of Sciences 45

among all eight Eumops species for which this has been reported), and a lower tip
index (the lowest among all species in the genus). Collectively, this suggests E.
floridanus has shorter or wider wings with shorter wing tips than most other
Eumops. While E. floridanus may not be capable of flight speeds as fast as some of
the other species in the genus, it may not need to fly as fast to generate enough lift
to remain airborne (Findley et al. 1972). When commuting through open space, E.
floridanus may incur slightly higher metabolic costs than other species in the genus,
but this may be compensated for with lower metabolic costs when maneuvering in
more confined air space (Voigt and Holderied 2012). Eumops floridanus may
encounter more clutter than other species in the genus, roosting in pines (Pinus
palustris and P. elliottii; Angell and Thompson 2016, Braun de Torrez et al. 2016)
located in pine flatwoods and scrubby flatwoods, which are more cluttered than the
desert areas typically inhabited by E. perotis and E. underwoodi. Future studies of
foraging habitat use and flight speeds of E. floridanus are recommended.
Knowledge of the ecology and physiology of E. floridanus is extremely
limited, yet is critical due to the species designation as federally endangered. The
morphological data we report serves as a foundation for our understanding of
sexual dimorphism, body condition, and flight capabilities of E. floridanus.We
found that these bats exhibit moderate sexual dimorphism in wing size, suggesting
there may be niche partitioning between sexes. Thus, we may need to consider the
foraging habitat use of males and females independently. The baseline body
condition and mass we report can be used in future studies to examine associations
between individual variation in physiological condition and environmental
conditions, habitat use, and movements.
Acknowledgments We thank the individuals who assisted with data collection, especially Ralph
Arwood, Josh Birchfield, Ryan Brown, Terry Doonan, Paula Halupa, Marilyn Knight, Jennifer Myers,
Kevin Oxenrider, Cason Pope, Jessica Reha, Frank Ridgeley, Kathleen Smith, Lisa Smith, and Seth
Sofferin. This research was funded through the Florida State Wildlife Grants Program and the Florida
Nongame Wildlife Trust Fund.
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Submitted: July 4, 2016
Accepted: August 25, 2016
Ober et al. Dimorphism in Eumops floridanus
48 Florida Scientist 80(1) 2017 QFlorida Academy of Sciences