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A new millipede (Austrotyla awishashola, n. sp., Diplopoda, Chordeumatida, Conotylidae) from New Mexico, USA, and the importance of cave moss gardens as refugial habitats

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Austrotyla awishoshola n. sp. is described from the moss gardens of one lava tube cave in El Malpais National Monument, Cibola Co., New Mexico. Most chordeumatidans require mesic conditions, and these environments are limited to moss gardens in several cave entrances and beneath cave skylights in El Malpais. Presently, this species is known from the moss gardens of a single of cave in the monument. We suggest A. awishoshola may be a climatic relict, having become restricted to the cave environment following the end of the Pleistocene. We discuss the importance of cave moss gardens as refugial and relictual habitats. Recommendations are provided to aid in the conservation and management of A. awishoshola and these habitats.
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Accepted by T. Wesener: 27 Jan. 2016; published: 25 Feb. 2016
ZOOTAXA
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Copyright © 2016 Magnolia Press
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http://doi.org/10.11646/zootaxa.4084.2.8
http://zoobank.org/urn:lsid:zoobank.org:pub:34B6A708-2B0D-4A7F-A78D-7A1C9E928BA6
A new millipede, Austrotyla awishoshola n. sp., (Diplopoda, Chordeumatida,
Conotylidae) from New Mexico, USA, and the importance of cave moss gardens
as refugial habitats
J. JUDSON WYNNE
1
& WILLIAM A. SHEAR
2
1
Department of Biological Sciences, Merriam-Powell Center for Environmental Research, Northern Arizona University, Flagstaff AZ
86011. E-mail: jutwynne@nau.edu
2
Department of Biology, Hampden-Sydney College, Hampden-Sydney VA 23943. E-mail: wshear@hsc.edu.
Abstract
Austrotyla awishoshola n. sp. is described from the moss gardens of one lava tube cave in El Malpais National Monu-
ment, Cibola Co., New Mexico. Most chordeumatidans require mesic conditions, and these environments are limited to
moss gardens in several cave entrances and beneath cave skylights in El Malpais. Presently, this species is known from
the moss gardens of a single of cave in the monument. We suggest A. awishoshola may be a climatic relict, having become
restricted to the cave environment following the end of the Pleistocene. We discuss the importance of cave moss gardens
as refugial and relictual habitats. Recommendations are provided to aid in the conservation and management of A. awisho-
shola and these habitats.
Key words: El Malpais National Monument, new species, cave, cave-restricted, relictual habitat
Introduction
The millipede genus Austrotyla Causey 1961 contains seven species, and occurs in two distinct regions in North
America: the Rocky Mountains from Alberta, Canada, to Chihuahua, Mexico (six species), and the upper
Mississippi Valley (one species). The genus was reviewed by Shear and Steinmann (2013), who described a new
troglobiotic species from Colorado and provided a key to the genus. In that paper, the authors referred to two
reports of the genus from New Mexico. The earliest was by Chamberlin (1910), who reported A. coloradensis
(Chamberlin, 1910) from Ruidoso, Grant County. Loomis (1943) stated he had seen specimens of A. montivaga
(Loomis, 1943) from Mescalero, Otero County. Both localities are within 450 km of El Malpais National
Monument. Unfortunately, these specimens could be found neither in 1970 (Shear 1971) nor for this study.
However, Shear & Steinmann (2013) expressed doubt that the Ruidoso collection represented A. coloradensis, a
species found much further north in Colorado, where it is relatively common and known from eleven counties.
Similarly, A. montivaga was described by Loomis (1943) from two localities in southeastern Arizona, but it is
unlikely the Mescalero specimens represented that species.
Within the Bandera Volcanic Field of western New Mexico, moss gardens occurring in cave entrances and
beneath skylights represent unique and important microhabitats (Lindsay 1951; Northrup & Welbourn 1997;
Wynne 2013) in an otherwise xeric landscape (Figs. 5, 6). In other parts of the world, moss gardens have yielded
numerous relict species now restricted to this environment (Benedict 1979; Wynne et al. 2014).
Cave biological work conducted by one of us (JW) in El Malpais National Monument resulted in the discovery
of Austrotyla awishoshola n. sp., the first chordeumatidan millipede confirmed in the state of New Mexico. We
describe this new species here, discuss moss gardens as refugial and relictual habitats, and make recommendations
for the conservation and management of this unique resource and its constituent species.
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Materials and methods
Study area. El Malpais National Monument (ELMA), located in Cibola County, New Mexico, encompasses
approximately 1,522 km
2
in the western part of the state. Featuring evidence of at least eight major volcanic
eruptions ranging in age from 100,000 to 3,000 years old (Cascadden et al. 1997), the national monument
comprises vast expanses of pahoehoe and ʻaʻā lava flows, cinder cones, ice caves, and at least 290 lava tube caves
(Wynne 2013). Biological inventories were focused on caves in close proximity to trails and roads and/or known to
support sensitive biological resources, including bat roosts.
Field sampling. During 7–15 October 2007, 8–15 October 2008 and 27–28 September 2014, the first author
led a team of technicians to conduct systematic arthropod inventories of 10 lava tube caves at ELMA. During the
2007–2008 work, we applied a systematic sampling approach to search for cave-dwelling arthropods. For each
cave visit, a team of three researchers uniformly applied four techniques: opportunistic collecting, baited pitfall
trapping, timed searches, and direct intuitive searches. For opportunistic collecting, the team collected
invertebrates encountered as they walked between sampling stations while deploying and removing pitfall traps
and conducting timed searches. Because we aimed to maximize the number of invertebrate species detected, we
sampled each cave from its entrance (i.e., drip line) to the back of the cave. Using available cartographic cave
maps, teams applied an interval sampling approach whereby 10% of each cave’s length was used as the sampling
interval (e.g., for a 100 m–long cave, sampling interval was every 10 m). All sampling stations were plotted on
each cave map. Three sampling stations (one at either wall and one at the cave centerline) were established at each
sampling interval. Fewer than three sampling stations per sampling interval were established in only two cases: (1)
when the cave passageway width was ≤5 m, one station was designated in the best available location and (2) when
exposed lava floors were encountered and no materials were available to aid in countersinking the trap, the
sampling station was skipped.
At each sampling station we deployed one pitfall trap and conducted two timed searches. The team conducted
timed searches within a 1 m radius of each pitfall trap station for a period of one to three minutes before traps were
deployed and prior to checking traps (protocol modified from Peck 1976). Each search was concluded after one
minute if no arthropods were detected and continued for a total of three minutes when arthropods were observed.
Because some caves contain unique microhabitats that support distinct arthropod communities and endemic
populations, we augmented the sampling protocol by conducting direct intuitive searches in those areas. These
microhabitats consist of moss gardens (Lindsay 1951; Lightfoot et al. 1994; Northrup & Welbourn 1997) at cave
entrances and beneath skylights (i.e., holes in the ground formed by the partial collapse of the cave roof), and tree
root “curtains” hanging from the ceilings in cave deep zones (Fig. 2). In each microhabitat we spent one hour (three
observers at ~20 minutes) searching for arthropods. Specifically, we searched tree root curtains hanging from the
ceilings in two caves (one hour per cave) and moss gardens in two caves (one hour per cave). Additionally, in
September 2014, the lead author searched for arthropods within the moss gardens of cave ELMA-008.
Cave codes. At the monument’s request, we used cave codes rather than actual cave names for all caves on
National Park Service lands. A copy of this report, which includes a table of cave names with associated cave
codes, is on file with monument headquarters in Grants, New Mexico, and the National Cave and Karst Research
Institute, Carlsbad, New Mexico.
Preservation and observation. As collected in the field, all material was preserved in 70% ethanol.
Identifications were based on morphological characters with the use of micropreparations. Line drawings were
made with the aid of a camera lucida mounted on an Olympus BX50 microscope. Specimens were air-dried and
coated with an Emitech SC 7620 sputter coater operating at 20 mA for 90 seconds, which typically results in a
coating of 240 Å of gold/palladium. Scanning electron micrographs were taken using a JEOL Neoscope JCM-5000
operating at 10 kV, and the images were refined using the open-source image-editing program GIMP; the plate was
assembled in Inkscape.
Taxonomy
Family Conotylidae Cook 1896
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Subfamily Austrotylinae Shear 1976
Genus Austrotyla Causey 1961
Shear & Steinmann (2013) provided a key to the seven known species of Austrotyla, including their newly
described A. stephensoni. Austrotyla awishoshola n. sp., will probably key out to A. montani Loomis & Schmitt,
1971, but may be distinguished by its occurrence in New Mexico, as opposed to Montana for A. montani, by its
much longer lobes on the femora of legs three and four of males, and differences in the gonopods.
Austrotyla awishoshola
n. sp.
Figs. 1–4
Austrotyla sp. Wynne 2013: A-5.
Types. Male holotype, one male and two female paratypes from cave ELMA-008, El Malpais National Monument,
Cibola Co., New Mexico, collected 13 October 2008; one male and two female paratypes from the same locality,
collected 28 September 2014, all collected by J. Judson Wynne. The gonopods of the male paratype (mounted on
an SEM stub) and all types are deposited at the Colorado Plateau Museum of Arthropod Biodiversity, Northern
Arizona University, Flagstaff.
FIGURES 1–4. Male Austrotyla awishoshola n. sp. Fig. 1. Anterior gonopods, posterior view. cp, coxal plate; pcp, posterior
coxal process; sp, sternal process. Fig. 2. Posterior gonopods, anterior view. bp, basal process; cx, coxite; pf, prefemur; t,
telopodite. Fig. 3. Left leg 3, posterior view. Fig. 4. Left leg 4, posterior view.
Diagnosis. Austrotyla coloradensis may occur in northern New Mexico, but can be distinguished from A.
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awishoshola in the strongly reduced basal angiocoxite branches and much larger sternal processes in the latter
(Figs. 1, 2). The other Colorado species, A. stephensoni Shear & Steinmann, 2013, has troglobiotic adaptations not
present in A. awishoshola. Austrotyla montivaga (Loomis, 1943), from Pima Co., Arizona, shares the reduced basal
angiocoxite branch with A. awishoshola, but has much smaller sternal processes. Austrotyla awishoshola has
femoral lobes on legpairs three and four that are distal in position, as in A. coloradensis, but which are at least twice
as long, in fact longer than in any other species of Austrotyla (Figs. 3, 4).
Etymology. The species name is a combination of two Zuni (the Puebloan Native American tribe, whose
historic aboriginal boundary includes present day ELMA) terms awisho and shola. Awisho means “moss” and
shola “many-legged creature.” Shola is a generic term used to describe centipedes, scorpions (Eriacho & Chavez
1998) and millipedes (Calvin Chimoni, pers. comm., 2015).
Description. Male holotype: Length, 8.5 mm, greatest width 0.7 mm. Ground color cream-tan, mottled
purplish brown, pigmentation strongest anteriorly, fading to nearly white at posterior end. Twenty-one well-formed
pigmented ocelli in triangular eyepatch. Antennae and legs of normal length proportionate to head and trunk.
Femora of legpairs 3 and 4 distinctly swollen, with elongate distal apophyses (Figs. 3, 4). Anterior gonopods (Fig.
1) with large, apically fimbriate processes arising from posterior surface of sternum (sp), angling first anteriorly
then posteriorly. Coxal plates (cp) erect, widely separated, narrower than in other species of genus, basolateral
translucent area strongly reduced, as is posterior coxite process (pcp). Posterior gonopods (Fig. 2) with coxites (cx)
erect, only slightly cupped, basal fimbriate branch (bp) large, sigmoidally curved; telopodite (t) about twice length
of prefemur (pf), about one-half as wide as long.
Female paratype: Length, 10 mm, greatest width 0.9 mm. Nonsexual characters as in male, but triangular
eyepatch with 29 or 30 ocelli.
Notes: The paratypes collected in 2014 show darker pigmentation than the holotype and paratypes collected in
2008; the lighter coloration of the 2008 specimens may be due to fading in the preservative. Pigmentation, eye size
and shape comparable to other epigean species of the genus and the proportional length of the antennae and legs do
not indicate morphological adaptation to the subterranean habitat in this species, suggesting a recent colonization
event (i.e., during the last glacial maxima) or perhaps dispersal from suitable habitat elsewhere.
Distribution. Austrotyla awishoshola is known from only one locality in western New Mexico—
approximately 30 km southwest of the city of Grants and within the Big Tubes Area of the Bandera Volcanic Field.
The single cave occurrence of this animal requires additional examination. A second cave, ELMA-012, with well-
developed moss gardens, occurs 0.22 km from ELMA-008. So it is reasonable to suggest this animal should occur
in both ELMA-008 and ELMA-012. Wynne (2013) applied the same sampling techniques and effort at both caves,
but only detected this animal in ELMA-008. Both Lightfoot et al. (1994) and Northrup & Welbourn (1997)
sampled the moss gardens of both caves, (as well as other caves on ELMA and adjacent lands) but did not detect
this species. Both caves are in the Bandera Volcanic Field, which is approximately 10,000 years old (Laughlin &
WoldeGabriel 1997). As the Pleistocene ended, both lava tube caves had recently formed. Collapses in the lava
tube conduits likely opened at different geologic times. As a result, the opportunity for wind-blown bryophyte
spores to colonize entrances and skylights forming suitable habitat for millipedes probably occurred at different
times as well. Perhaps ELMA-008 contained suitable A. awishoshola moss garden habitat, while ELMA-012 was a
closed lava tube conduit. Segments of the ELMA-012 conduit may have collapsed after the surface population of
A. awishoshola had already gone extinct. This would have greatly reduced the likelihood of A. awishoshola
reaching ELMA-012. Until it is detected elsewhere, we suggest A. awishoshola be considered a single cave
narrow-range endemic species.
Discussion
The mechanisms driving both A. awishoshola’s presence and isolation are of considerable interest to cave biology.
Wynne et al. (2014) identified 10 arthropod species on Easter Island restricted to moss gardens due to island-wide
human-induced environmental change. The authors suggest these species once occurred island-wide, but ultimately
became restricted to cave entrances. Austrotyla awishoshola may have a similar story. This species likely
represents a once wide-ranging species that occurred during the Pleistocene when the regional surface environment
contained suitable millipede habitat throughout. As the climate shifted and the surface habitats became unsuitable,
surface populations went extinct leaving at least the relict population beneath the skylight of cave ELMA-008.
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In similar situations, the “climatic relict hypothesis” (CRH) has been used to explain cave-restriction of
animals following Pleistocene climatic oscillations. However, CRH is typically applied to explain the occurrence
and isolation of troglomorphic taxa found in the temperate regions of the world (Jeannel 1943; Barr 1968).
Austrotyla awishoshola is not subterranean-adapted and is found in the xeric American Southwest. We suggest this
animal became restricted to cave moss gardens, and possibly crevices and mesocaverns in the lava beds, following
the climatic oscillations at the end of the Pleistocene. Thus, we believe A. awishoshola is a climatic relict.
Austrotyla awishoshola represents one of the relatively few millipede species known to occur in lava beds in
western North America. Perhaps the best known is Orthoporus ornatus (Girard, 1853) (Spirostreptida,
Spirostreptidae), a large juliform species studied by Crawford (i.e. 1979, 1988; Crawford et al. 1987) in the
Albuquerque Volcanic Field west of Albuquerque, New Mexico. This species has a wide range through the
southwestern United States and Mexico (Hoffman 1999). Crawford (1979) found that during dry periods, O.
ornatus sheltered in fissures and mesocaverns in the lava bed, but during the monsoon season, the mesic conditions
drew them to the surface in great numbers and they foraged on organic debris. As the humidity dropped, the
millipedes retreated into the cracks and crevices once again. Orthoporus ornatus shows no morphological signs of
adaptation for subterranean life.
In Craters of the Moon National Monument in Idaho, Idagona westocotti (Buckett & Gardner, 1967)
(Chordeumatida, Conotylidae) has been recorded from numerous lava tube caves but has not been found on the
surface. This species is widespread in the monument and in other nearby lava bed regions (Shear 2007).
Populations throughout this area appear to be morphologically uniform, especially compared to other species of the
genus. Idagona westcotti shows some degree of modification for subterranean life. Shear (2007) speculated that the
species inhabited small spaces throughout the lava flow (Mesovoid Shallow Substratum [MSS], see i.e. Gilgado et
al. 2015), and dispersed into lava tube caves accessible to researchers. Earlier on, Howarth (1983, 1996) supported
this idea by suggesting cave-adapted arthropods use fissures (i.e., mesocaverns) as their primary habitat and
colonize larger cave passages only when environmental conditions are suitable. Given the widespread
morphological uniformity, I. westcotti may be panmictic. However, molecular phylogenetics will be required to
address this question. A third example, Plumatyla humerosa (Loomis, 1943) (Chordeumatida, Conotylidae), is
similar (Shear 1971). Found in northern California and southern to central Oregon, P. humerosa has been collected
not only in lava tube caves, but also in limestone caves and mines. This animal is strongly adapted to the
underground environment. It is unknown whether the population in this large geographic area represents one
species or a species complex. Nevertheless, the presence of the animals in mines coupled with their troglobiotic
adaptations suggests MSS dispersal underground, as postulated for I. westcotti.
Austrotyla awishoshola has been found in one lava tube out of ten surveyed. Those ten tubes represent less
than one percent of the known tubes on the national monument and on adjacent private lands. Within lava tube cave
ELMA-008, A. awishoshola was collected only in a cave moss garden (Figs. 5, 6). Identified as one of the most
unique habitats in the region (Lindsay 1951), the moss gardens of ELMA caves may in one sense represent relict
habitats of the last glacial maximum (Lightfoot et al. 1994).
Moss gardens occur within collapse trench entrances or beneath skylights of lava tube caves where adequate
light is available for photosynthesis to occur. Presumably moisture flows into the cave through the entrance or is
funneled in via the skylight. The cool temperatures and higher humidity in the cave allow the moisture to persist.
Adventitiously, bryophyte spores colonized these areas giving rise to well developed moss garden communities. At
least 16 different bryophytes have been identified; most of which are alpine species requiring mesic environmental
conditions (Lindsay 1951; Lightfoot et al. 1994).
The moss garden habitat provides a refugium for animals, primarily arthropods, which would otherwise find
survival in lava tube caves difficult. These relictual features provide habitats for some arthropod species that may
have thrived on the surface (now Ponderosa Pine Forest) during the wetter, cooler conditions of Pleistocene glacial
maxima. While lava tube caves and MSS within the volcanic field may have once served as suitable habitat, this
would be difficult to confirm. Today, moss gardens are particularly suitable habitat for these organisms. This
habitat supports high biological diversity (Wynne 2013) and unique faunal assemblages, including a presumed
relict species of spider, Lepthyphantes turbatrix ((O. Pickard-Cambridge, 1877); Family Linyphiidae; Lightfoot et
al. 1994) and A. awishoshola. Additionally, Wynne (2013) reported range expansions for two tiphiid wasp species
(Tiphia andersoni Allen, 1971 and T. nona Allen, 1971) found as single specimens hibernating beneath rocks in
ELMA moss gardens.
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FIGURES 5, 6. Moss gardens in cave ELMA-008, El Malpais National Monument, New Mexico. Fig. 5. General view
showing the skylight (collapsed cave ceiling) permitting the entry of light to the moss garden below. Researcher provides scale.
Fig. 6. Closer view of moss gardens with basaltic boulders and organic debris beneath the skylight.
While A. awishoshola is presently known from just one restricted site, it is possible that it occurs in other
similar mesic habitats as well. The examples of other millipede species found in volcanic fields (discussed above)
underscore the possibility of animals sheltering in subterranean cracks and fissures (MSS) and historically
dispersing over larger areas, as may be the case for O. ornatus. A. awishoshola, as with O. ornatus, has no
characters indicative of adaptation to subterranean life. So, A. awishoshola could disperse via the surface when
cooler, moister conditions prevail. However, millipedes are considered poor dispersers. To ultimately reach and
colonize other suitable habitats would involve dispersing (via walking) during the appropriate surface conditions
and reaching suitable habitat (which meets their narrow environmental thresholds). While possible, such an event
would be rare and represent sweepstakes dispersal.
Aside from Austrotyla specus, found in both subterranean and surface habitats in the upper Mississippi River
valley, the remaining known species of Austrotyla from the United States are either associated with limestone and
lava tube caves, or found in high elevation forested habitats in the southwestern U.S. The latter localities (sky
islands) represent another kind of refugium because these features are surrounded by low elevation desert scrub.
Several soil arthropods that, during glacial maxima, had much wider distributions are now found only on sky
islands (Shelley & Medrano 2006; Cary & Jacobi 2008). Thus, it is possible that A. awishoshola or related species
may be found on sky islands as well. Indeed the previous but unsubstantiated reports of Austrotyla millipedes from
New Mexico are from such localities (Chamberlin 1910; Loomis 1943).
Conservation and management
Moss gardens of lava tube caves represent the most well developed communities of bryophytes (Lindsay 1951) and
are one of the most biologically unique features in the region (Lightfoot et al. 1994, Wynne 2013). Importantly, this
habitat has been identified as supporting at least two presumed relict species (Lightfoot et al. 1994, this paper) and
high arthropod biological diversity (Wynne 2013). Thus, we recommend this habitat continue to receive the highest
level of protection.
National Park Service personnel have made efforts to protect this habitat. The moss gardens occurring within
ELMA-012 have been roped off since 2002. We recommend these exclosures be routinely inspected and continue
to be maintained. We further recommend roping off moss gardens within ELMA-008, which is presently the only
known locality for A. awishoshola. Both caves share a common trailhead with an interpretative station describing
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the conservation importance of moss gardens. The interpretive station is dated and shows signs of weathering. We
recommend replacing the signage with new and revised interpretative placards describing the importance of moss
gardens and the animals occurring within these habitats.
Climate change models for the American Southwest predict decreased rainfall and a consistent drying trend
resulting in the region becoming increasingly more arid throughout the 21st century (Seager et al. 2007).
Decreased precipitation with subsequent drier conditions will likely adversely affect the moss garden habitat. To
address the impacts associated with climate change, we recommend (1) resampling and identifying moss species
present (the last survey was conducted by Lindsay 1951); (2) developing high-resolution maps of the moss
gardens’ extent with plotted locations of different bryophyte species; (3) establishing photo-monitoring stations to
track changes in the extent of moss gardens over time; and, (4) conducting a long term meteorological study of all
moss gardens to both establish baseline climatic conditions and track meteorological changes over time.
Nothing is known concerning A. awishoshola’s life history, population structure, habitat requirements or
distributional range. Global climate change will present further challenges to conservation and management. To
better define this millipede’s distributional range, additional caves and collapse features containing moss garden
habitats should be sampled. There are at least 40 lava tube caves and lava tube remnants and tunnel features with
moss gardens within ELMA and on adjacent private lands. While many of these features have been sampled during
previous work (Lightfoot et al. 1994; Northrup & Welbourn 1997; Wynne 2013), revisiting and resampling moss
gardens to systematically sample (refer to Wynne 2013) for A. awishoshola is recommended. Through such an
effort, we will be able to confirm whether or not this animal is indeed a single cave endemic. Through all of these
efforts, conservation biologists and resource managers will have much of the information necessary to better
manage and protect A. awishoshola.
Acknowledgements
Special thanks to Kayci Cook Collins, David Hays, Dana Sullivan, and Eric Weaver for their guidance and support
of this research. Ara Kooser, Jessica Markowski, Peter Polsgrove, and Kyle Voyles provided assistance in the field.
ELMA National Park Service staff (Steve Baumann and Calvin Chimoni) and Zuni Cultural Resources Advisory
Team (Octavius Seowtewa) provided the Zuni phase used to name the new species. Kyle Voyles co-developed the
arthropod sampling protocol. Alex Rivest provided images of moss gardens. We thank Jon Eisenback and Paul
Marek for access to and help with scanning electron microscopy at Virginia Tech. Fieldwork was funded through a
Colorado Plateau–CESU cooperative agreement between El Malpais National Monument and Northern Arizona
University. William Shear’s participation was supported by a grant (DEB-1256139) from the National Science
Foundation.
Literature cited
Barr, T.C. Jr. (1968) Cave ecology and the evolution of troglobites. Evolutionary Biology, 2, 35–102.
http://dx.doi.org/10.1007/978-1-4684-8094-8_2
Benedict, E.M. (1979) A new species of Apochthonius Chamberlin from Oregon (Pseudoscorpionida, Chthoniidae). Journal of
Arachnology, 7, 79–83.
Cary, S.J. & Jacobi, G.Z. (2008) Zoogeographic affinities of southwestern USA Plecoptera. International Advances in the
Ecology, Zoogeography, and Systematics of Mayflies and Stoneflies, 2008, 133–157.
http://dx.doi.org/10.1525/california/9780520098688.003.0011
Cascadden, T.E., Kudo, A.M. & Geisman, J.W. (1997) Discovering the relationships in a family of volcanoes: Cerro
Candelaria, Twin Craters, Lost Woman Crater and Lava Crater. New Mexico Bureau of Mines and Mineral Resources
Bulletin, 156, 41–52.
Chamberlin, R.V. (1910) Diplopods from the western states. Annals of the Entomological Society of America, 3, 233–262.
http://dx.doi.org/10.1111/j.1096-3642.1987.tb01344.x
Crawford, C.S. (1979) Desert millipedes: a rationale for their distribution. In: Camatini, M. (Ed.), Myriapod Biology, 1979, pp.
171–181.
Crawford, C.S. (1988) Nutrition and habitat selection in desert detritivores. Journal of Arid Environments, 14, 111–122.
Crawford, C.S., Berkovitz, K. & Warburg, M.R. (1987) Regional environments, life-history patterns and habitat use of
spirostreptid millipedes in arid regions. Zoological Journal of the Linnean Society of London, 89, 63–88.
WYNNE & SHEAR
292
·
Zootaxa 4084 (2) © 2016 Magnolia Press
http://dx.doi.org/10.1111/j.1096-3642.1987.tb01344.x
Eriacho, W. Sr. & Chavez, V. (1998) Shiwi'ma Isamma: Bena:we - Zuni Glossary. Zuni Public District No. 89, Zuni, New
Mexico, 137 pp.
Gilgado, J. D., Enghoff, H., Tinaut, A., Mauriès, J.-P. & Ortuño, V. (2015) Sierra Nevada (Grenada, Spain): a high-altitude
biogeographical crossroads for millipedes (Diplopoda) with first data on its MSS fauna and description of a new species of
the genus Ceratosphrys Ribaut, 1920 (Chordeumatida: Opisthocheiridae). Zootaxa, 4044 (3), 391–410.
http://dx.doi.org/10.11646/zootaxa.4044.3.4
Hoffman, R.L. (1980) Classification of the Diplopoda. Muséum d’Histoire Naturelle Genève, Gèneve, 237 pp.
Howarth, F.G. (1983) Ecology of cave arthropods. Annual Review of Entomology, 28, 365–389.
http://dx.doi.org/10.1146/annurev.en.28.010183.002053
Howarth, F.G. (1996) A comparison of volcanic and karstic cave communities. Proceedings of the International Symposium of
Vulcanospeleology (ed. by P. Oromi): 63–68. Available from: http://vulcanospeleology.org/sym07/ISV7x10.pdf (accessed
2 February 2016)
Jeannel, R. (1943) Les Fossiles Vivants des Cavernes. Gallimard.
Laughlin, A.W. & WoldeGabriel, G. (1997) Dating the Zuni-Bandera volcanic field. New Mexico Bureau of Mines and Mineral
Resources, Bulletin, 156, 25–29.
Lightfoot, D.C., Bleakly, D.L., Parmenter, R.R. & Gosz, J.R. (1994) Vegetation and Wildlife Inventory of El Malpais National
Monument: Final Report. Unpublished report on file with El Malpais National Monument, Grants, NM, 57 pp.
Lindsey, A.A. (1951) Vegetation and habitats in a southwestern volcanic area. Ecological Monographs, 21, 227–253.
http://dx.doi.org/10.2307/1943559
Loomis, H.F. (1943) New cave and epigean millipedes. Bulletin of the Museum of Comparative Zoology, 92, 373–410.
Northrup, D.E. & Welbourn, W.C. (1997) Life in the twilight zone—Lava tube ecology, natural history of El Malpais National
Monument. New Mexico Bureau of Mines and Mineral Resources Bulletin, 156, 69–82.
Peck, S.B. (1976) The effect of cave entrances on the distribution of cave inhabiting terrestrial arthropods. International
Journal of Speleology, 8, 309–321.
http://dx.doi.org/10.5038/1827-806X.8.4.1
Seager, R., Ting, M., Held, I., Kushnir, Y., Lu, J., Vecchi, G., Huang, H-P., Harnik, N., Leetmaa, A., Lau, N.-C., Li, C., Velez, J.
& Naik, N. (2007) Model projections of an imminent transition to a more arid climate in southwestern North America.
Science, 316, 1181–1184.
http://dx.doi.org/10.1126/science.1139601
Shear, W. A. (1971) The milliped family Conotylidae in North America, with a description of the new family Adritylidae
(Diplopoda: Chordeumatida). Bulletin of the Museum of Comparative Zoology, 141, 107–131.
Shear, W.A. (2007) Cave millipedes of the United States. V. The genus Idagona Buckett & Gardner (Chordeumatida,
Conotylidae, Idagoninae). Zootaxa, 1463, 1–12.
Shear, W.A. & Steinmann, D.B. (2013) Cave millipedes of the United States. XIII. A new, troglobiotic species of Austrotyla
from Colorado (Diplopoda, Chordeumatida, Conotylidae). Zootaxa, 3745, 486–490.
Shelley, R.M. & Medrano, M.F. (2006) Nesoressa crawfordi, n. gen., n. sp., a montane island milliped in New Mexico, USA;
proposal of a new tribe Nesoressini and preliminary cladogram of the lineage “Aniulina” (Julida: Parajulidae). Zootaxa,
1285, 31–50.
Wynne, J.J. (2013) Inventory, conservation and management of lava tube caves at El Malpais National Monument, New
Mexico. Park Science, 30, 45–55.
Wynne, J.J., Bernard, E.C., Howarth, F.G., Sommer, S., Soto-Adames, F.N., Taiti, S., Mockford, E.L., Horrocks, M., Pakarati,
L. & Pakarati-Hotus, V. (2014) Disturbance relicts in a rapidly changing world: the Rapa Nui (Easter Island) factor.
BioScience, 64, 711–718.
http://dx.doi.org/10.1093/biosci/biu090
... Effectively detecting troglomorphic and obligate troglophiles (cave-restricted) species presents further logistical considerations. These animals are typically endemic to a single cave or region (Borges et al., 2012;Christman, Culver, Madden, & White, 2005;Deharveng et al., 2008;Harvey, Berry, Edward, & Humphreys, 2008;Harvey et al., 2011;Niemiller & Zigler, 2013;Reddell, 1981;Shear, Taylor, Wynne, & Krejca, 2009;Tian, 2011;Wynne & Shear, 2016;Wynne et al., 2014) and often represented by small populations (Mitchell, 1970;Niemiller et al., 2017). Recognizing temporal and spatial heterogeneity of cave habitats (Chapman, 1983;Kane & Poulson, 1976;Pellegrini & Ferreira, 2013;Trontelj et al., 2012) is another important consideration. ...
... Because caves are highly heterogeneous in their distribution and occurrence of microhabitats, it is not possible to apply an interval sampling approach without either missing or ineffectively sampling areas that may support unique arthropod communities. We encountered moss gardens within entrances and beneath skylights of two (ELMA-0008 and ELMA-0012; Wynne, 2013;Wynne & Shear, 2016) and root curtains from two (ELMA-0303 and ELMA-0315; Wynne, 2013) ELMA caves. Fern-moss gardens occurred within entrances and beneath cave skylights of five of six lava tube caves on Rapa Nui . ...
... Regarding management concern species, nine new undescribed morphospecies were discovered, and two range expansions were documented on ELMA (Wynne, 2013). We detected three morphospecies using DIS only-a troglomorphic dipluran, Haplocampa n. sp.? (which was first observed by Northup & Welbourn, 1997), a potentially undescribed cave-adapted species of planthopper, Fulgoroidea n. sp.? (probably family Cixiidae) from the root curtains of two caves (Wynne, 2013) and a relict/cave-restricted millipede, Austrotyla awishoshola, Wynne & Shear, 2016; within the moss gardens of one cave (Wynne & Shear, 2016). For the remaining six undescribed species, two were detected by all techniques, one with both OC and DIS, two with TS only and one solely with PT. ...
Article
Aim: Identify the optimal combination of sampling techniques to maximize the detection of diversity of cave-dwelling arthropods. Location: Central-western New Mexico; northwestern Arizona; Rapa Nui, Chile. Methods: From 26 caves across three geographically distinct areas in the Western Hemisphere, arthropods were sampled using opportunistic collecting, timed searches, and baited pitfall trapping in all caves, and direct intuitive searches and bait sampling at select caves. To elucidate the techniques or combination of techniques for maximizing sampling completeness and efficiency, we examined our sampling results using nonmetric multidimensional scaling (NMDS), analysis of similarity (ANOSIM), Wilcoxon signed-rank tests, species richness estimators and species accumulation curves. Results: To maximize the detection of cave-dwelling arthropod species, one must apply multiple sampling techniques and specifically sample unique microhabitats. For example, by sampling cave deep zones and nutrient resource sites, we identified several undescribed cave-adapted and/or cave-restricted taxa in the southwestern United States and eight new species of presumed cave-restricted arthropods on Rapa Nui that would otherwise have been missed. Sampling techniques differed in their detection of both management concern species (e.g., newly discovered cave-adapted/restricted species, range expansions of cave-restricted species and newly confirmed alien species) and specific taxonomic groups. Spiders were detected primarily with visual search techniques (direct intuitive searches, opportunistic collecting and timed searches), while most beetles were detected using pitfall traps. Each sampling technique uniquely identified species of management concern further strengthening the importance of a multi-technique sampling approach. Main conclusions: Multiple sampling techniques were required to best characterize cave arthropod diversity. For techniques applied uniformly across all caves, each technique uniquely detected between ~40% and 67% of the total species observed. Also, sampling cave deep zones and nutrient resource sites was critical for both increasing the number of species detected and maximizing the likelihood of detecting management concern species.
... either occurred or still occurs in similar habitats on the surface, the importance of relict plant species restricted to cave entrances has been discussed for southern China (Monro et al. 2018). Additionally, several arthropod species globally are restricted to cave entrances in Polynesia (Mockford and Wynne 2013, Bernard et al. 2015, Taiti and Wynne 2015 and North America (Benedict 1979, Wynne andShear 2016) due to either extensive surface disturbance and glacial interglacial cycles, respectively. Thus, it is possible this species is a 'disturbance relict' restricted to the entrance of Shangshuiyan Cave and potentially other area cave entrances with similar vegetation. ...
... nov., discovered within a cave entrance vegetation community. As similar cave entrance vegetation communities have been identified as either supporting distinct relict plant communities and/or plant species in southern China (Monro et al. 2018), Easter Island, Chile ), and west-central New Mexico, USA (Lindsay 1951, Northrup and Welbourn 1997, Wynne 2013, their importance in supporting cave-restricted arthropod populations demonstrated (Northrup and Welbourn 1997, Wynne 2013, Wynne and Shear 2016, and widespread land cover conversion of both lowlands and uplands has occurred in China since 1958, this finding warrants both additional research into this species distribution, as well as a larger scale examination of other potential 'disturbance relict' arthropod species within cave entrance vegetation communities of the SCK. ...
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We synthesized the current knowledge of cave-dwelling millipede diversity from Guangxi Zhuang Autonomous Region (Guangxi), South China Karst, China and described six new millipede species from four caves from the Guilin area, northeastern Guangxi. Fifty-two cave-dwelling millipedes are known for the region consisting of 38 troglobionts and 14 troglophiles. Of the troglobionts, 24 are presently considered single-cave endemics. New species described here include Hyleoglomeris rukouqu sp. nov. and Hyleoglomeris xuxiakei sp. nov. (Family Glomeridae), Hylomus yuani sp. nov. (Family Paradoxosomatidae), Eutrichodesmus jianjia sp. nov. (Family Haplodesmidae), Trichopeltis liangfengdong sp. nov. (Family Cryptodesmidae), and Glyphiulus maocun sp. nov. (Family Cambalopsidae). Our work also resulted in range expansions of Pacidesmus trifidus Golovatch & Geoffroy, 2014, Blingulus sinicus Zhang & Li, 1981 and Glyphiulus melanoporus Mauriès & Nguyen Duy-Jacquemin, 1997. As with many hypogean animals in Southeast Asia, intensive human activities threaten the persistence of both cave habitats and species. We provide both assessments on the newly described species’ distributions and recommendations for future research and conservation efforts.
... These systems often support troglomorphic (subterranean-adapted) species with narrow geographic ranges (i.e., occurring within a single cave or watershed [6][7][8][9][10][11][12][13][14][15]) and are often represented by small populations [16,17]. Cave entrances have also been identified as important habitats for relict arthropod species from the last glaciation [18][19][20][21][22] and extensive surface disturbance [23][24][25]. While some areas have been identified as hotspots for endemism and diversity [7,26], cave communities in most regions globally remain largely unknown. ...
Article
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Since the initial experiments nearly 50 years ago, techniques for detecting caves using airborne and spacecraft acquired thermal imagery have improved markedly. These advances are largely due to a combination of higher instrument sensitivity, modern computing systems, and processor intensive analytical techniques. Through applying these advancements, our goals were to: (1) Determine the efficacy of methods designed for terrain analysis and applied to thermal imagery; (2) evaluate the usefulness of predawn and midday imagery for detecting caves; and (3) ascertain which imagery type (predawn, midday, or the difference between those two times) was most informative. Using forward stepwise logistic (FSL) and Least Absolute Shrinkage and Selection Operator (LASSO) regression analyses for model selection, and a thermal imagery dataset acquired from the Mojave Desert, California, we examined the efficacy of three well-known terrain descriptors (i.e., slope, topographic position index (TPI), and curvature) on thermal imagery for cave detection. We also included the actual, untransformed thermal DN values (hereafter "unenhanced thermal") as a fourth dataset. Thereafter, we compared the thermal signatures of known cave entrances to all non-cave surface locations. We determined these terrain-based analytical methods, which described the "shape" of the thermal landscape hold significant promise for cave detection. All imagery types produced similar results. Down-selected covariates per imagery type, based upon the FSL models, were: Predawn-slope, TPI, curvature at 0 m from cave entrance, as well as slope at 1 m from cave entrance; midday-slope, TPI, and unenhanced thermal at 0 m from cave entrance; and difference-TPI and slope at 0 m from cave entrance, as well as unenhanced thermal and TPI at 3.5 m from cave entrance. Finally, we provide recommendations for future research directions in terrestrial and planetary cave detection using thermal imagery.
... Historically, the "climatic relict hypothesis" has been used to explain the occurrence and isolation of troglomorphic taxa found in the temperate regions of the world (Jeannel 1943;Barr 1968). Wynne and Shear (2016) proposed that a new species of millipede, Austrotyla awishoshola Wynne & Shear, 2016 (from western New Mexico), lacking characteristics of cave adaptation, was restricted to cave moss gardens, and perhaps also the crevices and mesocaverns within the lava beds of the region. This animal's restriction to the subterranean environment may have happened during the climatic oscillations at the end of the Pleistocene. ...
Article
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Disparrhopalites naasaveqw n. sp. is described from a cave at Wupatki National Monument, Arizona. It differs from D. patrizii (Cassagnau & Delamare Deboutteville, 1953) in having pigment and a well-developed ungual cavity, and from D. tergestinus Fanciulli, Colla & Dallai, 2005 by having pigment, 8+8 eyes and a well-developed ungual tunica. Dietersminthurus enkerlinius Palacios-Vargas, Cuéllar & Vázquez, 1998 is transferred to Disparrhopalites Stach, 1956 as D. enkerlinius (Palacios-Vargas, Cuéllar & Vázquez, 1998) n. comb. The sminthurid subfamily Songhaicinae Sánchez-García & Engel, 2016 (type genus Songhaica Lasebikan, Betsch & Dallai, 1980) is redefined and the genera Disparrhopalites, Gisinurus Dallai, 1970, Soqotrasminthurus Bretfeld, 2005 and Varelasminthurus Da Silva, Palacios-Vargas & Bellini, 2015 are transferred to this subfamily. A key is provided for separation of included genera. Effects of climate change on presumed cases of cave restriction in the American Southwest are discussed.
... Interestingly, a single male (AMNH) had been collected in 1965 in Lava River Cave by Jean and Wilton Ivie, but evidently went unrecognized as a new species. Given the propensity of lava tube troglobionts to disperse through the porous lava (Crawford 1993;Wynne & Shear 2016), T. marchingtoni probably will be found in many other localities in the Newberry lava fields. ...
Article
Full-text available
The ischyropsalidoid genus Taracus Simon 1879 is reviewed and all previously named species are redescribed. Taracus nigripes Goodnight & Goodnight, 1943 is synonymized with T. packardi Simon 1879, and T. malkini Goodnight & Good-night 1945 with Oskoron spinosus (Banks) 1894; the type locality of T. gertschi Goodnight & Goodnight 1942 is corrected from "eastern Oregon" to Rose Lake, Idaho, based on original labelling. The following new species of Taracus are de-scribed: T. carmanah (Vancouver Island), T. marchingtoni (Oregon), T. taylori, T. spesavius (both Nevada), T. timpano-gos (Utah), T. audisioae, T. ubicki, and T. fluvipileus (all California). A new genus Oskoron is based upon O. spinosus (Banks) 1894, originally described in Taracus, and also includes two new species, O. brevichelis (Oregon, Washington) and O. crawfordi (Washington). New locality records extend the known distribution of Taracus to the Canadian provinces of Alberta and British Columbia and the US states of Montana, Wyoming, Utah, Nevada and New Mexico. Schönhofer's (2013) proposal of a family Taracidae for Taracus, Hesperonemastoma Gruber 1970 and Crosbycus Roewer 1914 is dis-cussed.
... Interestingly, a single male (AMNH) had been collected in 1965 in Lava River Cave by Jean and Wilton Ivie, but evidently went unrecognized as a new species. Given the propensity of lava tube troglobionts to disperse through the porous lava (Crawford 1993;Wynne & Shear 2016), T. marchingtoni probably will be found in many other localities in the Newberry lava fields. ...
Article
Full-text available
The ischyropsalidoid genus Taracus Simon 1879 is reviewed and all previously named species are redescribed. Taracus nigripes Goodnight & Goodnight, 1943 is synonymized with T. packardi Simon 1879, and T. malkini Goodnight & Goodnight 1945 with Oskoron spinosus (Banks) 1894; the type locality of T. gertschi Goodnight & Goodnight 1942 is corrected from “eastern Oregon” to Rose Lake, Idaho, based on original labelling. The following new species of Taracus are described: T. carmanah (Vancouver Island), T. marchingtoni (Oregon), T. taylori, T. spesavius (both Nevada), T. timpanogos (Utah), T. audisioae, T. ubicki, and T. fluvipileus (all California). A new genus Oskoron is based upon O. spinosus (Banks) 1894, originally described in Taracus, and also includes two new species, O. brevichelis (Oregon, Washington) and O. crawfordi (Washington). New locality records extend the known distribution of Taracus to the Canadian provinces of Alberta and British Columbia and the US states of Montana, Wyoming, Utah, Nevada and New Mexico. Schönhofer’s (2013) proposal of a family Taracidae for Taracus, Hesperonemastoma Gruber 1970 and Crosbycus Roewer 1914 is discussed.
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Subterranean ecosystems are among the most widespread environments on Earth, yet we still have poor knowledge of their biodiversity. To raise awareness of subterranean ecosystems, the essential services they provide, and their unique conservation challenges, 2021 and 2022 were designated International Years of Caves and Karst. As these ecosystems have traditionally been overlooked in global conservation agendas and multilateral agreements, a quantitative assessment of solution-based approaches to safeguard subterranean biota and associated habitats is timely. This assessment allows researchers and practitioners to understand the progress made and research needs in subterranean ecology and management. We conducted a systematic review of peer-reviewed and grey literature focused on subterranean ecosystems globally (terrestrial, freshwater, and saltwater systems), to quantify the available evidence-base for the effectiveness of conservation interventions. We selected 708 publications from the years 1964 to 2021 that discussed, recommended, or implemented 1,954 conservation interventions in subterranean ecosystems. We noted a steep increase in the number of studies from the 2000s while, surprisingly, the proportion of studies quantifying the impact of conservation interventions has steadily and significantly decreased in recent years. The effectiveness of 31% of conservation interventions has been tested statistically. We further highlight that 64% of the reported research occurred in the Palearctic and Nearctic biogeographic regions. Assessments of the effectiveness of conservation interventions were heavily biased towards indirect measures (monitoring and risk assessment), a limited sample of organisms (mostly arthropods and bats), and more accessible systems (terrestrial caves). Our results indicate that most conservation science in the field of subterranean biology does not apply a rigorous quantitative approach, resulting in sparse evidence for the effectiveness of interventions. This raises the important question of how to make conservation efforts more feasible to implement, cost-effective, and long-lasting. Although there is no single remedy, we propose a suite of potential solutions to focus our efforts better towards increasing statistical testing and stress the importance of standardising study reporting to facilitate meta-analytical exercises. We also provide a database summarising the available literature, which will help to build quantitative knowledge about interventions likely to yield the greatest impacts depending upon the subterranean species and habitats of interest. We view this as a starting point to shift away from the widespread tendency of recommending conservation interventions based on anecdotal and expert-based information rather than scientific evidence, without quantitatively testing their effectiveness.
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Ever-increasing human pressures on cave biodiversity have amplified the need for systematic, repeatable, and intensive surveys of cave-dwelling arthropods to formulate evidence-based management decisions. We examined 110 papers (from 1967 to 2018) to: (i) understand how cave-dwelling invertebrates have been sampled; (ii) provide a summary of techniques most commonly applied and appropriateness of these techniques, and; (iii) make recommendations for sampling design improvement. Of the studies reviewed, over half (56) were biological inventories, 43 ecologically focused, seven were techniques papers, and four were conservation studies. Nearly one-half (48) of the papers applied systematic techniques. Few papers (24) provided enough information to repeat the study; of these, only 11 studies included cave maps. Most studies (56) used two or more techniques for sampling cave-dwelling invertebrates. Ten studies conducted ≥10 site visits per cave. The use of quantitative techniques was applied in 43 of the studies assessed. More than one-third (42) included some level of discussion on management. Future studies should employ a systematic study design, describe their methods in sufficient detail as to be repeatable, and apply multiple techniques and site visits. This level of effort and detail is required to obtain the most complete inventories, facilitate monitoring of sensitive cave arthropod populations, and make informed decisions regarding the management of cave habitats. We also identified naming inconsistencies of sampling techniques and provide recommendations towards standardization.
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The communities of cave-adapted animals recently discovered in lava tubes and tropical caves provide systems to independently test evolutionary theories developed from historic biospeleological studies in temperate limestone caves. Limestone caves are usually old, deep, large, three-dimensional mazes, with few mesocaverns and subject to complex geological history often including uplift, folding, and subsidence. Compared to limestone caves, lava caves are usually younger, shallower, smaller, less complex mazes, with more abundant mesocaverns and with a simpler history. In spite of these major contrasts resulting from differences in parent rock and mode of formation, specialized subterranean animals living in both lava and karstic caves display remarkably similar adaptations, indicating that selection pressures and ecology must be similar. Indeed, there are important ecological similarities. Once beyond the influence of entrances, the physical environment in subterranean habitats is perpetually dark, humid, and nearly isothermal; lacks most environmental cues; and often contains lethal or sublethal gas mixtures and wet barren rocky substrates. Even though the types and sources of food vary among regions and caves, the difficulties of finding food resources as well as finding mates in dark three-dimensional mazes are similar. For both rock types, numerous cave-sized and smaller passages exist that have no entrance allowing access to humans, and also at least some of the surface over both is often barren with food resources sinking into subterranean voids out of the reach of surface species. Troglobites evolved to exploit these resources in the harsh subterranean environment. Because of their different geological histories, lava and limestone cave communities may accumulate and lose species differently over time. In limestone caves, succession progresses downward, with younger habitats deeper below the surface. Succession in lava tubes is opposite, with younger habitats near the surface and older habitats deeper. New lava flows continually rejuvenate aging cave habitats in volcanically active areas, allowing for specialized species to occur in exceptionally young caves.
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Populations of cave invertebrates are generally considered to be food-limited. The cave entrance is a major source of food input into the community in the form of decaying organic matter. Thus, the densities of scavenging terrestrial cave invertebrates should be related to the distance from the cave entrance because this represents a measure of food abundance. A test showed this expectation to be true in Crossings Cave, Alabama. A population density peak occurred 10 m inside the cave where the dark zone and detritus infall regions meet. The greatest population peak occurred at 100 m where densities of crickets and their guano are highest. The pattern should hold for most caves, but the actual distances will vary in each site depending on its circumstances. When the fauna was removed from the cave, the remnant had not regained community equilibrium a year later. Removal of the dominant scavenger, a milliped, allowed other species populations to expand because of decreased competitions.
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Millipedes (Diplopoda), with a few notable exceptions, are poor dispersers, showing a very high degree of endemicity, not the least in mountains. The first samplings of the Mesovoid Shallow Substratum (MSS) of the higher altitudes of the Sierra Nevada Mountains (Baetic System, Southern Spain) have led to the discovery of a high number of millipedes, each of the species present showing a different degree of establishment in this subterranean environment. An update of the knowledge on the millipedes of this region, the first data of the millipede communities in the MSS and the description of Ceratosphys cryodeserti Gilgado, Mauriès & Enghoff n. sp. are here provided, as well as the first data on the humidity and temperature fluctuations in the MSS of this high mountain. The new species is similar to other Baetico-Riffan species, while the only previously known congener from the region, C. soutadei Mauriès, 1969, has more similarities to certain Pyrenean species. Biogeographical relationships of all the captured species are also discussed.
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Caves are considered buffered environments in terms of their ability to sustain near-constant microclimatic conditions. However, cave entrance environments are expected to respond rapidly to changing conditions on the surface. Our study documents an assemblage of endemic arthropods that have persisted in Rapa Nui caves, despite a catastrophic ecological shift, overgrazing, and surface ecosystems dominated by invasive species. We discovered eight previously unknown endemic species now restricted to caves—a large contribution to the island's natural history, given its severely depauperate native fauna. Two additional species, identified from a small number of South Pacific islands, probably arrived with early Polynesian colonizers. All of these animals are considered disturbance relicts—species whose distributions are now limited to areas that experienced minimal historical human disturbance. Extinction debts and the interaction of global climate change and invasive species are likely to present an uncertain future for these endemic cavernicoles.
Chapter
This chapter examines the zoogeographic affinities of 75 Plecoptera species in New Mexico and Arizona. The findings indicate that in four major physiographic subdivisions of the study area, stonefly species arrange themselves in ways that reveal dispersal corridors, dispersal barriers, and refugia which operated during late Pleistocene pluvial and post-pluvial Holocene environments. The results also suggest that the southwestern Plecoptera fauna are distinct in their species composition, taxonomic representation, and level of endemism.
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Nesoressa crawfordi, n. gen., n. sp., is proposed for a slender parajulid milliped inhabiting high elevation boreal forests on five inselberg mountains in Cibola and Socorro counties, New Mexico; it is anatomically incompatible with established tribes, so Nesoressini, n. tribe, is erected to accommodate it. A sixth population existed 27 years ago in "caves near ice caves," Cibola County, but its presence today awaits confirmation. In addition to nemasomatid-like body dimensions, N. crawfordi is characterized by an elevated pleurotergal "shield" on the caudal margin of the gonopodal aperture, simple anterior gonopods possessing a sternum, telopodites, & large coxal lobes, and posterior gonopod (pg) telopodites comprising three closely appressed projections-long, parallel, nearly identically configured prefemoral processes & solenomeres and shorter, spiniform branches "C." The disjunct populations of N. crawfordi appear to be relicts from a continuous Pleistocene population in central New Mexico that fragmented into localized vicariants as the climate warmed and dried in the post-Pleistocene era. As the pgs are joined by a sclerotized sternum, Nesoressa/Nesoressini appears to be the sister-group to a clade consisting of tribes lacking this structure. A clade "Aniulina" is postulated comprising Nesoressini + (Parajulini + (Aniulini + Gosiulini)) that originated in the Rio Grande border region of the US and Mexico, its present center of diversity. Apacheiulus Loomis, 1968, a potential synonym of Gosiulus Chamberlin, 1940, is assigned to the Gosiulini, and the tribes Bollmaniulini & Karteroiulini, both established by Causey, 1974, are tentatively regarded as synonymous.
Chapter
Obligatory cavernicoles, or troglobites, have traditionally been of special interest to evolutionary biologists for several reasons. The existence of animal life in caves and other subterranean spaces at first attracted attention because of its novelty; intensive biological exploration of caves began little more than a century ago. Although the discovery and description of the cave faunas of the world is far from complete, especially in the Western Hemisphere, so much descriptive information has been compiled that we can safely assert that, at least in unglaciated, temperate parts of the world, the occurrence of numerous species of troglobites in any major limestone region is a common and highly probable phenomenon.
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