Forthcoming title due to be published May 2008 Dominican

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1 Forthcoming title due to be published May 2008 Dominican Amber Spiders A comparative palaeontologicalneontological approach to identification, faunistics, ecology and biogeography Dr David Penney Siri Scientific Press Special Offer on pre-publication orders! (until 15th April 2008) Please see below for further details and sample pages

2 Book details and ordering information Title: Dominican Amber Spiders Subtitle: A comparative palaeontological neontological approach to identification, faunistics, ecology and biogeography Author: David Penney Publisher: Siri Scientific Press ISBN: Forthcoming Publication date: Expected May 2008 Dimensions: 245 by 170 mm Cover: Soft (300 gsm, gloss laminated) Number of pages: 178 (130 gsm silk coated paper) Number of illustrations: 300+ including high quality colour photos Summary: see attached sample pages Price: (postage, packaging & handling extra, but free for prepublication orders*) Methods of payment Paypal: please make payment to spiderdavep Direct bank transfer: for further details please the author on david.penney@manchester.ac.uk Cheque or international money order: please make payable (in GBP sterling) to David Penney and send to: Dr David Penney, 50 Burnside Drive, Burnage, Manchester, M19 2LZ, United Kingdom Please note that only payment in Sterling (Great British Pounds) can be accepted. Whichever form of payment you use, please the following information to david.penney@manchester.ac.uk: your name, delivery address and method of payment (please put Amber Spider Book in the subject field). Receipts will be issued when the book is despatched. Thank you! *refers to regular, surface mail only. The publisher and author accept no responsibility in the unlikely event of orders lost in transit. Delivery by registered mail or courier can be arranged, with additional costs paid by the purchaser. Please contact the author for details.

3 The author is a Visiting Research Fellow at the University of Manchester, UK and the leading world expert on fossil spiders preserved in amber and in interpreting what they can reveal about the ecology of the extinct forests in which they lived. In this book Dr Penney provides a comprehensive synopsis of what is known about the Dominican Republic amber spider fauna, much of which is based on his numerous scientific publications in leading international journals. However, the book is not intended solely for academics. It contains more than 300 illustrations including many colour photographs, which should permit the identification of both the fossil and living Hispaniolan spider fauna by both amber collectors and spider enthusiasts. The introductory chapters provide full coverage of what is known about the geological origins, chemistry and botanical source of Dominican amber and the mining, preparation and distribution processes. which the author has witnessed first hand. Previously unpublished data on historical biogeography should make this book of interest to all those interested in the biogeography of the Caribbean region. The volume also contains an extensive bibliography of almost 350 entries providing a valuable resource for anybody interested in fossil resins. This book far surpasses anything else availabe on this subject and is expected to remain the leading reference work for many years to come. Bar code here David Penney Dominican Amber Spiders Siri Scientific Press Dominican Amber Spiders A comparative palaeontologicalneontological approach to identification, faunistics, ecology and biogeography Dr David Penney

4 Foreword It is not possible to fully appreciate the origins, evolutionary history or present biodiversity of any group of organisms until one considers the fossil record. Yet despite this obvious statement, there often remains a palpable void between the disciplines of palaeontology and neontology, and scientists from both camps are to blame. More often than not, neontologists will not even consider fossils in systematic studies or when describing new taxa. However, this is not a universal phenomenon and I am encouraged by the increasing number of neontologists who do consider fossils. In some cases they may be unaware that fossils exist, but given the electronic bibliographic databases that are currently available this is not really a credible excuse. Others argue that fossils do not preserve sufficient detail for comparative studies with recent specimens. However, as you will see in this volume, recent applications of high-resolution imaging technology to palaeontological specimens render this argument one of semantics or methodology. Some neontologists have told me they do not consider fossils in their studies because they are unimportant and they remain steadfast in this respect despite my repeated attempts to convince them otherwise. A perfect example of just how important it is to consider fossils relates to the spider family Archaeidae, which was first described in 1854 from fossils preserved in Baltic amber, prior to being found in the extant fauna three decades later. Not only are fossils of this family important from a taxonomic and nomenclatorial perspective, but fossils can also shed much light on the historical biogeography of this family. The extant fauna is restricted to South Africa and Madagascar, whereas fossils are known from the Baltic region, France, Myanmar, China and Kazakhstan. Many palaeontologists are accidental zoologists. For some, having graduated from an Earth Sciences degree course, most of their academic background lies in the physical, rather than biological sciences. Many are unfamiliar with the finer details of taxonomic practices for extant members of the groups they then choose to go on and study. There are many examples in the literature of new fossil taxa that have been erected solely on the basis of age. In many cases, there is no indication that comparative extant specimens have been examined, the diagnoses are often based on features not considered reliable for extant species, nor do the diagnoses serve to differentiate the fossil taxa from living forms. Given that many groups of organisms demonstrate a high degree of evolutionary stasis, such an approach is inappropriate. Using such an approach makes comparisons of neontological and palaeontological faunistic datasets (e.g., in order to assess any degree of change over time) impossible or highly misleading. As a zoologist turned palaeontologist I sit in both camps and suppose I am an accidental geologist. I also have a lot of catching up to do! Ultimately however, researchers from both these (and other) disciplines need to enter into each others realms in order to address effectively the increasingly complex macro-scale evolutionary and biological questions that we currently pose in order to secure research funding to understand the history of life on Earth. This book has four main purposes. Firstly, to demonstrate a perfect example of how fossil and extant faunas can be extremely similar and thus warrant a combined neontologicial and palaeontological taxonomic approach. Secondly, to show how comparisons of faunas based on such an approach can permit qualitative and quantitative investigations of interesting palaeo/biological questions, for example, relating to palaeoecology and historical biogeography. Thirdly, to provide comprehensive information on our current knowledge regarding the origins and formation of Hispaniola and Dominican Republic amber, including methods for preparation and study. Finally, the book serves as an introduction to the fossil record of spiders, and specifically, the identification of spiders preserved as fossils in Dominican Republic amber (and also from the extant Hispaniolan fauna). It is not intended as an exhaustive guide for species identification, but should permit the reader to identify their specimen at least to family, and in some cases even further. Readers will then be directed to the relevant literature required to take their identifications to species level. Thus, this volume is aimed at a broad audience and some will have a better knowledge of the subject than others. Rather than include a comprehensive glossary, I have attempted to limit technical terms and explain them where they appear in the text. Finally, it is easy to start an endeavour such as this, and indeed it was a labour of love. However, it is not so easy to know when to stop. New fossil and extant species are being discovered and described all

5 Contents 1. Introduction...10 Caught in the act...11 What are spiders and how do they fit into the grand scheme of things?...13 Spiders in the fossil record...15 Age, radiations and extinction events...17 What is the importance of fossil spiders and why should we study them? Dominican Republic amber...21 Some history...22 A note on terminology...23 Botanical source and age of Dominican amber...23 The amber producing tree...23 Age of Dominican amber...25 Physical and chemical properties...26 Tissue and DNA preservation...27 Authenticity (distinguishing amber from copal and fakes)...28 The mining process...28 The amber mines...29 The extraction process...29 From mine to museum...30 Methods of preparation and study...31 Preparation of raw amber inclusions...31 Further preparation for closer scrutiny of inclusions...33 Light microscopy and photography...34 Advanced microscopy and computed tomography...35 Major collections of Dominican amber...37 Conservation and curation of amber collections...37 The diversity of Dominican amber inclusions History of Hispaniolan araneology...40 The extant fauna...40 The fossil fauna...41 Systematic checklist of fossil and extant Hispaniolan spiders Key to Hispaniolan spider families (fossil & extant)...48 Morphology and terminology...48 Key to the spider families of Hispaniola...52 Highly distinctive morphological features...52 Dichotomous key to all Hispaniolan spider families Family descriptions...65 Dipluridae...66 Cyrtaucheniidae...67 Microstigmatidae...67 Barychelidae...68 Theraphosidae...69 Filistatidae...70

6 8 Sicariidae...71 Scytodidae...72 Drymusidae...73 Ochyroceratidae...73 Pholcidae...75 Caponiidae...77 Tetrablemmidae...78 Segestriidae...78 Oonopidae...79 Palpimanidae...81 Mimetidae...81 Oecobiidae...83 Hersiliidae...84 Deinopidae...86 Uloboridae...87 Nesticidae...89 Theridiidae...90 Theridiosomatidae...94 Symphytognathidae...95 Anapidae...96 Mysmenidae...96 Linyphiidae...97 Nephilidae...99 Tetragnathidae Araneidae Lycosidae Pisauridae Oxyopidae Zoridae Ctenidae Desidae Dictynidae Amaurobiidae Miturgidae Anyphaenidae Liocranidae Clubionidae Corinnidae Trochanteriidae Prodidomidae Gnaphosidae Selenopidae Sparassidae Philodromidae Thomisidae Salticidae...125

7 9 6. Aspects of palaeoecology & historical biogeography The Miocene Dominican amber forest Resin as a trap: taphonomy and bias of amber spider inclusions The site of resin secretion The entrapment process Do different ambers trap organisms in the same way? Bias in the amber fauna Comparison of the fossil and extant spider faunas Origins of the Hispaniolan spider fauna Predictions for the extant fauna based on the fossil fauna Other fossil arachnids in Dominican amber References cited Index...171

8 10 Introduction When most people hear the word fossil they tend to conjure up images of giant dinosaurs such as Tyrannosaurus rex or shelled marine molluscs. Prior to the Hollywood blockbuster movie Jurassic Park, which was based on recreating dinosaurs through extracting their DNA from blood in the guts of fossil mosquitoes preserved in amber, few people would entertain the notion that insects occur in the fossil record. However, insects, spiders and other terrestrial arthropods are common as fossils (Grimaldi & Engel, 2005) and particularly so in amber, where they are often preserved with life-like fidelity. Amber has properties similar to amorphous, polymeric glass and is the fossilized form of tree resin, which consists of a complex mixture of terpenoid and/or phenolic compounds. It is derived from numerous different tree families (e.g., Pinaceae, Araucariaceae, Cupressaceae, Leguminoseae, Combretaceae to name but a few), most of which can be determined by comparing the infrared spectra of the amber with those of resins from extant tree species. Such techniques also serve to differentiate one amber type from another. For example, Baltic amber has a highly characteristic plateau off one side of one of the spectrograph peaks, which is referred to as the Baltic shoulder. The oldest ambers that contain fossil arthropods are from the Lower Cretaceous of Lebanon (Poinar & Milki, 2001) and Jordan (Kaddumi, 2005), although there is no reason not to expect future discoveries of inclusions in older (e.g., Jurassic) fossil resins. Various deposits from around the world (Figure 1.1) fill in the gaps from the Cretaceous until the present, although hardened resins younger than 40,000 years of age are considered to be sub-fossil and are called copal (not shown in Figure 1.1). Amber is a prime example of a Konservat-Lagerstätte (an occurrence of exceptional preservation, which permits detailed morphological comparisons with living relatives) and so in contrast to most fossils preserved in sediments, amber inclusions are particularly important from a phylogenetic perspective and can be used to investigate micro- as well as macro-evolutionary processes.

9 Amber deposits of the world. Data primarily from Martínez-Delclòs et al., 2004) with updates Caught in the act Syninclusions (two or more inclusions in the same piece of amber) often preserve interactions between organisms, for example, behaviours such as mating (Figure 1.2), mate guarding, commensalism, parasitism (e.g., nematode worms exiting their arthropod host, hymenopteran larvae and mites preserved in situ, still penetrating the cuticle of their host organism), disease (e.g., pathogenic fungi), defecation, egg laying, phoresy (one organism being transported by another pseudoscorpions are sometimes found attached to the legs of insects), predation and maternal care (e.g., ants carrying larvae and pupae). Even delicate spider webs are occasionally preserved, sometimes with prey attached (Figure 1.3). So excellent is the degree of preservation in amber that even the tiny glue droplets of spider viscid silk are often clearly visible (Figure 1.4), even in Cretaceous ambers dating back to in excess of 100 million years (Zschokke, 2003, 2004). Amber may also preserve the death throes of the entombed arthropods as they struggled to escape the sticky exudates, for example, in the form of wing movements and disarticulation of body parts. Fossilized spider blood was reported recently, exuding from joints where the resin had caused the legs to autospasize (detach as a result of an external force) from the body (Penney, 2005a; Figure 1.5). Such observations as those listed above are rarely, if ever, encountered in the non-amber fossil record because of the different taphonomic processes (what happens to the organism between death and becoming a fossil) that control the preservation of organisms in carbonate rocks and amber (Martínez-Delclòs et al., 2004). However, I do not wish to imply here that the non-amber fossil record is any less important. An additional consequence of this variation is that, on the whole, sediments and amber preserve different subsets of the arthropod community. Thus, the fossil record of amber is biased towards preserving certain groups, as are all other fossil deposits. In addition, the fossil record in general is notoriously incomplete, but not

10 27 exuded, the volatile components of the resin, such as sesquiterpene hydrocarbons which function to control viscosity and flexibility, are gradually lost to produce hardened resin. In general, the processes involved in fossilization seem to be progressive oxidation and polymerization via free-radical mechanisms. In contrast to Baltic amber, Dominican amber does not contain succinic acid. Thus, the new species name Staphylococcus succinus erected by Lambert et al. (1998) for a newly discovered species of bacterium in Dominican amber is slightly inappropriate. Tissue and DNA preservation The mode of tissue preservation in amber appears to be a rapid and thorough fixation and dehydration, which may be sufficient for preserving deoxyribonucleic acid (DNA) more consistently than any other kind of fossilization process (Grimaldi et al., 1994a). Henwood (1992) reported excellent preservation of soft tissues, including locomotory, digestive, respiratory, nervous and sensory tissues from cantharid and nitulid beetles preserved in Dominican Republic amber. However, not all ambers preserve internal tissues in such detail. For example, the recently discovered amber from western Amazonia appears to preserve only the cuticular exoskeleton of the arthropod inclusions (Antoine et al., 2006). During the early 1990s numerous researchers claimed that they had managed to extract small strings of DNA from Dominican amber inclusions, such as the stingless bee Propblebeia dominicana (Cano et al., 1992), a termite Mastotermes electrodominicus (DeSalle et al., 1992, 1993), a wood gnat Valeseguya disjuncta (DeSalle, 1994) and the amber producing tree itself (Poinar et al., 1993). Even more impressive were claims by Cano et al. (1993) of DNA extraction from a beetle Libanorhinus succinus in Lebanese amber, dating back as far as 135 million years. A number of publications rode the crest of the amber DNA wave (e.g., Poinar, 1994), including a whole book by Poinar & Poinar (1994), which is a very pleasant read and particularly useful for those intending to visit amber producing areas. However, an excellent study by Austin et al. (1997) at the Natural History Museum, London, which employed a rigorous experimental method with appropriate control groups, was unable to replicate the abovementioned studies. DNA was retrieved (including from the control samples, which should not have contained any!) but all sequences detected were derived from obvious non-insect contaminants, such as vertebrates and fungi. Thus, they concluded that the likelihood of DNA being preserved in amber was minimal, but such negative results cannot disprove its existence. Kimberly et al. (1997) were unable to replicate DNA extraction from Dominican amber Propblebeia, despite using nine specimens and nested amplifications, which greatly enhanced the sensitivity of the assay process. Stankiewicz et al. (1998) found that relatively resistant macromolecules, such as lignin, cellulose and chitin were extremely degraded in Dominican amber plant and insect inclusions, concluding that the persistence of fragile molecules such as DNA would be highly improbable. This century, more recent claims (Rogers et al., 2000) have proposed that rapidly dehydrated inclusions may contain undamaged DNA. However, Hebsgaard et al. (2005) pointed out that many research groups currently accept one hundred thousand to one million years as the maximum age range for DNA survival, based on both theoretical and empirical data, and that despite the problems associated with modelling the long-term survival of DNA in the geosphere, the claims of DNA from amber (1,000-fold older than theoretical predictions for maximal DNA survival) are cause for concern, regardless of how good a preservative the natural resin is. According to these authors, all claims for amber DNA to date suffer from inadequate experimental design and insufficient authentification criteria. Some of the earlier proponents for DNA extraction have now held up their hands and admitted that it looks like the end of the road for fossil DNA, whereas others still support their findings; the burden of proof now lies with the latter. The jury is still out on whether or not it is possible to extract DNA from amber, or indeed whether it remains in tact in fossilized resin, but given the evidence to hand it would seem unlikely. A particularly interesting study by Koller et al. (2005) used a new technique for internal fixing of amber inclusions in association with electron microscopy and histochemical staining. They noted that cellular

11 29 the principal amber deposits of the eastern Baltic (Wu, 1997). Under the close scrutiny of Rafael Trujillo, the then dictatorial head of the government, a West German company began extracting and exporting unprocessed amber in large quantities. However, it wasn t long before the Dominican government withdrew the mining rights for political and economic reasons and the company collapsed shortly thereafter. The government also prohibited the export of unprocessed amber, permitting only finished goods to leave the country (Wu, 1997). The amber mines The mines in the Cordillera Septentrional are located slightly north of Santiago (Figure 2.1) and are often named after local villages. They include: Palo Quamado, Palo Alto, Juan de Nina, La Toca, Las Cacaos, Los Aguitos, La Cumbre, Los Higos, La Bucara, Pescado Bobo, El Naranjo, Las Auyamas, El Arroyo, Aquacate, Carlos Diaz and Villa Trina. Most of these mines are located 800 1,000 m above sea level and can only be accessed by hiking along steep mountain trails. Those in the Cordillera Oriental are situated at elevations of less than 200 m above sea level and include: La Medita and Ya Nigua near El Valle. Two additional sites (Comatillo and Sierra de Agua) are located at Bayaguana in the lowlands near Cotui (Poinar, 1992: table 4). The mines consist primarily of tunnels leading deep into the sides of mountains and occasionally they form deep, vertical pits dug into the ground. The extraction process The amber mines at La Toca are particularly noted for producing vertebrate fossils. They are little more than hand-carved tunnels dug into the side of the rock, that follow a vein of the amber-containing blue-grey sediments (Figure 2.5). None of the mining process is mechanized. The tunnels are excavated using hammers and chisels, with illumination provided by candlelight; far from the industrialized process depicted in the movie Jurassic Park. The tunnels are damp, slippery, unlit, extremely cramped and may extend up to 200 m into the hillside. It is not possible to stand in the tunnels, which have barely any supporting structures built in (Figure 2.6). The trunk posts visible in Figures 2.5 and 2.6 are to assist 2.5 A La Toca amber mine in the Cordillera Septentrional 2.6 The author descending into the La Toca amber mine 2.7 Miners holding a drainage pipe for pumping out water following flooding of the mine

12 VHR-CT scans of a spider in Paris amber (family Micropholcommatidae) from Penney et al. (2007). (a) dorsal view; (b) ventral view; (c) anterior view; (d) posterior view; (e) lateral view; (f) lateral sectioned view; (g) right pedipalp dorsal view; (h) right pedipalp posterior view; (i) left pedipalp retrolateral view; (j) right pedipalp prolateral view (body length approx. 1 mm)

13 48 Key to Hispaniolan spider families The spider family keys presented here are modified primarily from Jocqué & Dippenaar-Schoeman (2006) and should permit the identification of both the fossil and extant spider fauna recorded from Hispaniola to date. Some families are currently known either from the fossil or the extant fauna alone, which is not to say that they will not be discovered from the other fauna at a later date. Jocqué & Dippenaar-Schoeman (2006) also provided an identification key based on spider web structure; not particularly useful for amber-preserved spiders, but a fabulous aid to identifying living spiders in the field. Morphology and terminology The basic body plan of spiders is shown in Figure (4.1), with more specific features illustrated throughout the key and in the family description pages. They have two major tagma (body parts) joined by a narrow pedicel through which the circulation, nervous and feeding systems are canalized: the anterior prosoma and the posterior opisthosoma. The prosoma is covered dorsally by the carapace, which is divided into two regions: the anterior cephalic region (where the eyes are situated) and the posterior thoracic region (often containing a fovea a distinct depression which serves as an internal point for muscle attachment). In some species the division of these regions is distinct, demarcated by a cervical groove, whereas in others it is not noticeable; both situations may occur in a single family. The shape and surface texture of the carapace (including pitting and arrangement of setae, etc.) can be important taxonomic features. For example, the spider family Scytodidae (spitting spiders) are recognizable immediately by their high, convex carapace that has evolved to contain the enlarged posterior lobe of the venom gland, which occupies much of the prosoma. Most spiders have eight eyes in two rows, although some families have fewer, or even no eyes at all. The basic arrangement consists of two rows of four eyes each. These eye rows may be straight, recurved or

14 49 DORSAL VIEW pedipalp chelicera VENTRAL VIEW chelicera fang pedipalp procurved eye row carapace fovea pedicel sigilla cardiac mark abdomen spinnerets book lung epigyne spiracle coxa trochanter femur patella tibia metatarsus tarsus tarsal claws recurved eye row AME: anterior median eye ALE: anterior lateral eye PLE: posterior lateral eye maxilla labium sternum cheliceral stridulatory file MOQ: median ocular quadrangle PME: posterior median eye cribellum trichobothria spinnerets & anal tubercle calamistrum on leg 4 metatarsus spine tarsal scopula tarsal claws with claw tuft simple haplogyne pedipalp complicated entelegyne pedipalp epigyne 4.1 General spider morphology

15 53 Vertical orb-web decorated with stabilimenta: Araneidae Horizontal orb-web of ecribellate silk: Tetragnathidae Horizontal orb-web of cribellate silk: Uloboridae Leg morphology: Tarsi and metatarsi of first legs with distinctive prolateral scopula (4.3): Palpimanidae Front leg with distinctive tibial and metatarsal clasping spurs (4.4): Mysmenidae Femur of first pair of legs with sclerotized spot ventro-subdistally (4.5): Mysmenidae Third pair of legs directed forwards rather than backwards: Segestriidae Legs very long and slender, with few or no spines: Pholcidae, Ochyroceratidae (some Theridiidae and Scytodidae) Tarsi of fourth pair of legs with comb of serrated setae (4.6): Theridiidae, Nesticidae Tibiae and metatarsi of first two pairs of legs with distinct prolateral spination consisting of a series of short spines, interspersed with a series of longer, slightly curved spines (4.7): Mimetidae Legs without spines, first femur enlarged, tibia, metatarsus and tarsus of first two pairs of legs with ventral cusps (4.8): Trachelas (Corinnidae) Tarsi distinctly longer than metatarsi: Anapidae Legs with many, extremely long prominent spines: Oxyopidae Tiny spiders with femur of fourth pair of legs distinctly thicker than the other femora: Orchestina (Oonopidae) Apex of metatarsi with soft, trilobate membrane (very difficult to see) (4.9): Sparassidae Claw tufts consisting of several rows of lamelliform setae (4.10): Anyphaenidae First pair of legs long and directed forward, femora with long trichobothria; metatarsus four with a calamistrum set in a depression: Uloboridae Tibia of third pair of legs only, with double row of trichobothria: Mangora (Araneidae) All tibiae with many long (2 4 leg diameter) trichobothria: Theridiosomatidae Legs laterigrade with anterior two pairs distinctly thicker and longer than posterior two (4.11): Thomisidae Metatarsus of second leg with a retrolateral excavation in the distal half, bearing a single, prominent retrolateral spine (4.12): Misionella (Filistatidae) Metatarsi with flexuous zones (very difficult to see): Hersiliidae Metatarsus of legs three and/or four with a preening brush (4.13): Gnaphosidae Tarsi two-clawed, with prolateral claw distinctly more pectinate: Selenopidae Prosoma (excluding leg) morphology: Anterior median eyes very large (4.14): Salticidae Posterior median eyes very large (4.15): Deinopidae Posterior median eyes of irregular shape (4.16, 4.17): Gnaphosidae, Prodidomidae Spider with only two eyes: Nops (Caponiidae) Spider with only four eyes: Tetrablemmidae, some Uloboridae Eight eyes in two rows: anterior with six, posterior with two (4.18): Selenopidae Lateral eyes on tubercles: Thomisidae Eight eyes in a hexagonal arrangement, anterior medians smallest (4.19): Oxyopidae Cephalic region of carapace the head strangely modified: Linyphiidae (Erigoninae) and some Theridiidae (e.g., Faiditus) Thoracic region of carapace distinctly domed (six eyes) (4.20): Scytodidae Clypeus forming a conical projection terminating in a sphere, both fringed with setae: Floricomus (Linyphiidae) Chelicerae large with distinct projections (4.21): Tetragnathidae, some Corinnidae (e.g., Megalostrata)

16 55 Sternum with pit organs on promargin (4.22): Theridiosomatidae Male palpal tibia widened distally and rim with a single row of long setae (4.23): Theridiidae Opisthosoma morphology: Tiny spiders with conspicuous large, hairy anal tubercle (4.24): Oecobiidae Abdomen with large spiny outgrowths: some Araneidae (e.g., Gasteracantha, Micrathena) Tracheal spiracle broad, positioned well forward of the spinnerets: Anyphaenidae Abdomen extending beyond the spinnerets: Filistatidae, some Theridiidae and Pholcidae Abdomen flat and wedge-shaped, wider behind (long spinnerets) (4.25): Hersiliidae Anterior spinnerets as long as abdomen, long distal segment with spigots all along its median side (4.25): Hersiliidae Anterior spinnerets as long as abdomen and widely separated, distal segment without spigots along its median side (4.26): Dipluridae Anterior lateral spinnerets advanced on ventral side of abdomen and widely separated, bearing elongated piriform gland spigots (4.27): Zimiris (Prodidomidae) Spinnerets tubular in appearance: Gnaphosidae Dichotomous key to all Hispaniolan spider families 1. Fangs close parallel to longitudinal axis of the body (paraxial), two pairs of booklungs (4.28): Section 1: Mygalomorphae Fangs close at 90 o to longitudinal axis of the body (diaxial), one pair of booklungs (or maybe absent) (4.29): Araneomorphae 2 2. Calamistrum (metatarsus of fourth leg) and cribellum present (sometimes absent in males) (4.30): Section 2: Cribellate spiders Calamistrum and cribellum absent: Ecribellate spiders 3 3. Less than eight eyes: Section 3 Eight eyes: 4 4. Tarsi with two claws: Section 4: Dionycha Tarsi with three claws: Section 5: Trionycha Sometimes the third (unpaired) claw can be difficult to see in fossils Section 1: Mygalomorphae 1. Tarsi with two claws: 2 Tarsi with three claws: 3 2. Leg tarsi with clavate trichobothria along their length (4.31); apical segment of posterior spinnerets long and finger-like; anterior lobe of endites well developed (4.32); clypeus often wide: Theraphosidae Leg tarsi with no, or only 4 6 clavate trichobothria basally; apical segment of posterior spinnerets short and dome-shaped; anterior lobe of endites not well developed: Barychelidae 3. Body covered with blunt-tipped clavate setae; booklung openings small and oval (4.33): Microstigmatidae Body without blunt-tipped or clavate setae; booklung openings slit-like: 4

17 Araneid palp ?

18 65 Family descriptions The primary aim of this chapter is to permit the identification of Dominican amber fossil (and extant Hispaniolan) spiders to family level. In some cases it may also facilitate identification to genus or even species. I have tried to avoid the use of overly spider-specific technical terms wherever possible, because I want general amber collectors to be able to use it as easily as more experienced arachnologists. For this reason, I have concentrated only on the morphological features important for identification and have not provided extensive, detailed accounts of all parts of spider anatomy for each family. For those interested, this information can be found in Jocqué & Dippenaar-Schoeman (2006). Also, in many instances the identification information is specific to the Hispaniolan taxa, rather than to the family as a whole. The relevant publications include primarily those that record taxa from Hispaniola for the first time, rather than global or continental revisionary studies of particular groups. Such works can be located easily using Platnick s online World Spider Catalogue. Similarly, the additional notes relate primarily to the Hispaniolan fauna and again I have tried to avoid too much information regarding complicated systematic and phylogentic studies, but in places have included interesting snippets of such.

19 66 INFRAORDER MYGALOMORPHAE FAMILY DIPLURIDAE Simon, 1889 Funnel web mygalomorphs Dominican amber, extinct taxa Masteria sexoculata (Wunderlich, 1988); Ischnothele? sp.; Masteria sp. Hispaniola, extant taxa Ischnothele jeremie Coyle, 1995; Ischnothele garcia Coyle, 1995 Identification The Hispaniolan diplurids are small for mygalomorph spiders, having a carapace length of approximately 5 mm in the extant species and only 1.5 mm in the fossil species. Chelicerae porrect, long fangs, furrows with distinct teeth. Eight eyes (six in the fossil species) in a compact group; ocular area twice as wide as long (Figure 5.1). Four spinnerets widely spaced; posterior pair very long (Figure 5.2). Tarsi with three claws, scopulae absent. Male pedipalps as in Figures 5.3 and Masteria sexoculata 5.4 Ischnothele jeremie 5.1 Extant Ischnothele carapace 5.2 Extant Ischnothele in lateral view 5.5 Masteria sp. in amber Natural history These spiders spin funnel webs that consist of two functionally distinct parts: a tubular retreat hidden in an existing crevice, such as between rocks or the roots of a tree, and an exposed fan-like capture web. Additionally, the webs often serve as homes to kleptoparasitic spiders (see Mysmenidae). Relevant publications Schawaller (1982a), Wunderlich (1988, 2004), Coyle (1995), Raven (1985, 2000) Additional notes The strictly fossil genus Microsteria Wunderlich, 1988 was synonymized with the extant genus Masteria L. Koch, 1873 by Raven (2000). Raven examined the holotype of M. sexoculata Wunderlich, 1988 and was unable to determine the characters proposed by Wunderlich (1988) as diagnostic for the genus, thus he synonymized the genus with Masteria (Raven, 2000). Wunderlich (2004: 619) doubted Raven s synonymy and provided additional characters in validation of Microsteria. Given Raven s expertise with mygalomorph spiders the synonymy was retained by Penney (2006b). The specimen described as Ischnothele? sp. (Figure 5.5) by Schawaller (1982a) was transferred to the genus Masteria by Raven (1985: 161). Wunderlich (1988) also described a specimen as Ischnothele? sp. However, according to Coyle (1995: 29) the carapace and palpal

20 Male Faiditus crassipatellaris; note the raised ocular region and the abdomen extending beyond the spinnerets 5.67 Photograph and drawing of male Styposis pholcoides 5.70 Male Dipoena altioculata; note the raised ocular region with an extremely high clypeus (DG) 5.68 Male Lasaeola vicinoides in lateral (top) and dorsal (bottom) views; note the cylindrical carapace (DG) 5.71 Female Spintharus longisoma; note the kite-shaped abdomen with two distinct humps (KL)

21 101 FAMILY TETRAGNATHIDAE Menge, 1866 Four-jawed spiders Dominican amber, extinct taxa Azilia hispaniolensis Wunderlich, 1988; Cyrtognatha weitschati Wunderlich, 1988; Homalometa fossilis Wunderlich, 1988; Leucauge sp.; Tetragnatha pristina Schawaller, 1982 Hispaniola, extant taxa Agriognatha argyra Bryant, 1945; A. espanola Bryant, 1945; A. rucilla Bryant, 1945; Antillognatha lucida Bryant, 1945; Azilia montana Bryant, 1940? [specimen was a juvenile female]; Chrysometa bigibbosa (Keyserling, 1864); C. conspersa (Bryant, 1945); C. cornuta (Bryant, 1945); C. maculata (Bryant, 1945); C. obscura (Bryant, 1945); C. sabana Levi, 1986; Glenognatha mira Bryant, 1945; Hispanognatha guttata Bryant, 1945; Leucauge argyra (Walckenaer, 1842); L. regnyi (Simon, 1897); L. venusta (Walckenaer, 1842); L. venustella Strand, 1916; Metabus ebanoverde Álvarez-Padilla, 2007; Tetragnatha elongata Walckenaer, 1842; T. nitens (Audouin, 1826); T. orizaba (Banks, 1898); T. pallescens F.O.P.-Cambridge, 1903; T. tenuissima O.P.-Cambridge, 1889 Identification Small to large spiders with eight eyes in two rows. The basic body plan of this family is highly variable, but quite distinct in some genera (e.g., Tetragnatha spp.; Figure 5.90). The carapace is longer than wide and the chelicerae vary from short and stout to highly modified (especially in mature males), with rows of large teeth and large projecting spurs (Figures 5.91 & 5.92). Legs often long and spinose, with three tarsal claws. Leucauge has a distinctive double row of trichobothria in the proximal half of the prolateral surface of the femur of the fourth leg (not to be confused with uloborids which also possess a calamistrum). The opisthosoma also varies from elongate in Tetragnatha (Figure 5.90) to globular in Glenognatha. In Leucauge and Azilia it extends caudally beyond the spinnerets, the latter sometimes has small dorsal humps (Figure 5.93). The pedipalp of mature males is relatively simple, with a large paracymbium and the conductor and embolus coiled distally (Figure 5.94); often cymbial processes are present Pedipalp of Tetragnatha pristina 5.90 Tetragnatha body plan (male) 5.92 Chelicerae of Cyrtognatha weitschati 5.93 Abdomen of Azilia 5.91 Chelicerae of Tetragnatha pristina

22 Lyssomanes viridis; note the eyes are in four rows (WM) Anterior view of Salticidae showing the enlarged anterior median eyes AME ALE PLE PME Menemerus bivittatus on tree trunk Lyssomanes pristinus, a large and relatively common species in Dominican amber; note the elongate cymbium Dorsal view of Salticidae in Dominican amber showing the typical eye arrangement: AME (anterior median eyes), ALE (anterior lateral eyes), PME (posterior median eyes), PLE (posterior lateral eyes) Corythalia scissa, sometimes the retrolateral tibial apophysis lies flush with the cymbium and can be difficult to see Some of the variation in fossil salticid pedipalps

23 129 Aspects of palaeoecology & historical biogeography The life histories and behaviour of spiders are relatively well differentiated at the family level, and spider assemblages can be indicative of particular climatic conditions. The principal of behavioural fixity in the fossil record is well documented and states that the behaviour, ecology, and climatic preferences of fossil organisms will be similar to those found in their present-day descendants at the generic and often family level (e.g., Boucot, 1989). The close similarity of the Dominican Republic amber spider fauna at supraspecific (i.e., genus and family) level to the extant Neotropical spider fauna (see later and Penney, 1999, 2005d, 2007b; Penney & Pérez-Gelabert, 2002) supports the idea that the climate of Hispaniola at the time of the Dominican Republic amber resin formation was tropical. This chapter assesses how the fossil and extant Neotropical araneofaunas can be used together to investigate various interesting questions relating to the palaeoecology and historical biogeography of the region.

24 DEVONIAN PALEOZOIC MISS. PENN PERMIAN TRIASSIC MESOZOIC JURASSIC CRETACEOUS 95 CENOZOIC PALEOGENE NEOGENE Age (Ma) ARANEAE 6.5 Evolutionary tree of spiders highlighting the fossil (red circles) and Recent (blue text) Hispaniolan faunas Attercopus Unplaced families include Chummidae, Cybaeidae, Cycloctenidae, Hahniidae, Homalonychidae, Synaphridae, Ephalmatoridae (fossil) and Insecutoridae (fossil) ghost lineage based on phylogenetic relationship possible ancestral relationship fossil spiders described from Dominican Republic amber hypothesised relationships KEY range extension based on phylogenetic relationships period of Dominican Republic amber resin secretion range based on published record of described specimen(s) OPISTHOTHELAE MYGALOMORPHAE ARANEOMORPHAE Triassaraneus + Argyrarachne ATYPOIDEA HAPLOGYNAE DIVIDED CRIBELLUM CLADE CANOE TAPETUM CLADE DEINOPOIDEA ORBICULARIAE JURARANEIDAE ARANEOIDEA THERAPHOSODINA RASTELLOIDINA PALEOCRIBELLATAE ERESOIDEA PALPIMANOIDEA DIONYCHA RTA CLADE AMAUROBIOIDS Lycosoidea indet. SYMPHYTOGNATHOIDS MESOTHELAE ATYPIDAE ANTRODIAETIDAE MECICOBOTHRIIDAE HEXATHELIDAE DIPLURIDAE NEMESIIDAE MICROSTIGMATIDAE BARYCHELIDAE PARATROPIDIDAE THERAPHOSIDAE CYRTAUCHENIIDAE IDIOPIDAE CTENIZIDAE ACTINOPODIDAE MIGIDAE HYPOCHILIDAE GRADUNGULIDAE AUSTROCHILIDAE FILISTATIDAE CAPONIIDAE TETRABLEMMIDAE SEGESTRIIDAE DYSDERIDAE ORSOLOBIDAE OONOPIDAE PHOLCIDAE DIGUETIDAE PLECTREURIDAE OCHYROCERATIDAE LEPTONETIDAE TELEMIDAE SCYTODIDAE PERIEGOPIDAE DRYMUSIDAE SICARIIDAE OECOBIIDAE HERSILIIDAE ERESIDAE UNPLACED ENTELEGYNES* MIMETIDAE MALKARIDAE LAGONOMEGOPIDAE SPATIATORIDAE HUTTONIIDAE STENOCHILIDAE PALPIMANIDAE MICROPHOLCOMMATIDAE HOLARCHAEIDAE PARARCHAEIDAE MECYSMAUCHENIIDAE ARCHAEIDAE NICODAMIDAE TITANOECIDAE PHYXELIDIDAE DICTYNIDAE ZODARIIDAE CRYPTOTHELIDAE SPARASSIDAE ANYPHAENIDAE CLUBIONIDAE CORINNIDAE ZORIDAE LIOCRANIDAE? PHILODROMIDAE SALTICIDAE SELENOPIDAE THOMISIDAE CITHAERONIDAE AMMOXENIDAE TROCHANTERIIDAE GALLIENIELLIDAE LAMPONIDAE GNAPHOSIDAE PRODIDOMIIDAE NEOLANIDAE STIPHIDIIDAE AGELENIDAE AMPHINECTIDAE DESIDAE AMAUROBIIDAE TENGELLIDAE ZOROCRATIDAE PISAURIDAE TRECHALEIDAE LYCOSIDAE PARATTIDAE PSECHRIDAE SENOCULIDAE OXYOPIDAE CTENIDAE ZOROPSIDAE MITURGIDAE DEINOPIDAE ULOBORIDAE NEPHILIDAE ARANEIDAE TETRAGNATHIDAE LINYPHIIDAE PIMOIDAE BALTSUCCINIDAE CYATHOLIPIDAE SYNOTAXIDAE NESTICIDAE THERIDIIDAE PROTHERIDIIDAE THERIDIOSOMATIDAE MYSMENIDAE ANAPIDAE SYMPHYTOGNATHIDAE with 39 shared families (Figure 6.5), equating to a similarity value of 75%. The similarity values for genera (Figure 6.7) are considerably lower at 15%; 26 genera are currently considered strictly fossil. However, such genera have, in the past, been subsequently discovered in the extant fauna (see later) or synonymized with recent genera. For example, Raven (2000: 573) synonymized Microsteria Wunderlich, 1988 with Masteria L. Koch, 1873 (Dipluridae), so this value is considered an upper limit for the taxa described to date. The species similarity is 0% because all described Dominican amber fossil and sub-fossil spiders are currently considered

25 Continental affiliations of fossil and extant Hispaniolan spiders. (a) Extant genera recroded from Dominican Republic amber. (b) Genera recorded from the Recent Hispaniolan fauna. (c) Extant genera from the amber and Recent Hispaniolan faunas combined. (d) Continental species distributions for extant genera recorded in Dominican Republic amber. (e) Continental species distributions for genera recorded from the Recent Hispaniolan fauna. (f) Continental species distributions for both faunas combined. effects). Current geological and palaeontological evidence suggests that all on-island lineages forming the extant fauna must be younger than Middle Eocene (<40 million years; Iturralde-Vinent & MacPhee, 1999). So what can the above analyses of fossil and extant spider faunas reveal about the continental origins of this relatively young Neotropical fauna? Firstly, based on the relative geographical distributions of shared genera, the Caribbean fauna probably did not originate from North America. In fact, some of the shared spider genera recorded from North America result from Caribbean originators, not vice versa (Reiskind, 2001). The shared values for Central and South America are reasonably similar when the faunas are compared at generic level, with slightly higher values for the former (Figure 6.8a c). However, it must be remembered that the Panamanian isthmus arose long after the Dominican amber was formed. The great biotic interchange (GBI) (Stehli & Webb, 1985) following the establishment of this land connection between North and South America masks the former distributions of taxa and accounts for the observed similarity of the Central and South American faunas. Additional complications result from the fact that the North American fauna is better known than either the Central, South or West Indian faunas. Indeed, the low percentage similarity between the fossil amber fauna and the on-island fauna would tend to suggest the latter is poorly known, a fact recently demonstrated by Penney (2004b) and Hormiga et al. (2007). Within the last two years alone, five spider families have been recorded from the extant Hispaniolan fauna for the first time: Prodidomidae (Platnick & Penney, 2004), Hersiliidae (Rheims & Brescovit, 2004) and Ochyroceratidae, Mysmenidae and Symphytognathidae (Hormiga et al., 2007). Further similarities presumably result from more recent anthropogenic introductions and through emigration and immigration of highly dispersive taxa to and from all neighbouring regions, masking the earlier achievements of taxa with low dispersal capabilities (see later). Thus, although we see patterns emerging at generic level, we need higher resolution in order to generate a clearer picture. The comparative analyses of the continental species distributions for genera shared with both the fossil and extant Hispaniolan faunas clearly indicate greatest affinities with South America

26 Biodiversity Research. Nova Science Publishers Inc., New York. Penney, D. & Drew, B A novel technique for extracting Segestria spp. from their retreats. Newsl. Br. Arachnol. Soc., 76: 2 3. Penney, D. & Langan, A.M.L Comparing amber fossils across the Cenozoic. Biol. Letts., 2: Penney, D. & Ortuño, V.M Oldest true orb-weaving spider (Araneae: Araneidae). Biol. Letts., 2: Penney, D. & Pérez-Gelabert, D.E Comparison of the Recent and Miocene Hispaniolan spider faunas. Rev. Ibér. Aracnol., 6: Penney, D. & Selden, P.A Assembling the Tree of Life Phylogeny of Spiders: a review of the strictly fossil spider families. Acta Zool. Bulgarica, supplement 1: Penney, D. & Selden, P.A Fossils explained: Spinning with the dinosaurs: the fossil record of spiders. Geol. Today, 23: Penney, D., Wheater, C.P. & Selden, P.A Resistance of spiders to Cretaceous Tertiary extinction events. Evolution, 57: Penney, D., Dierick, M., Cnudde, V., Masschaele, B., Vlassenbroeck, J., Van Hoorebeke, L. & Jacobs, P First fossil Micropholcommatidae (Araneae), imaged in Eocene Paris amber using x-ray computed tomography. Zootaxa, 1623: Pérez-Asso, A.R. & Pérez-Gelabert, D.E Checklist of the millipedes (Diplopoda) of Hispaniola. Bol. S.E.A., 28: Pérez-Gelabert, D.E Catálogo sistemático y bibliografía de la biota fósil en ámbar de al República Dominicana. Hispaniolana (N. Ser.), 1: Pérez-Gelabert, D.E Preliminary checklist of the Orthoptera (Saltatoria) of Hispaniola. J. Orthoptera Res., 10: Pérez-Gelabert, D.E Arthropods of Hispaniola (Dominican Republic and Haiti): a checklist and bibliography. Zootaxa, in press. Pérez-Gelabert, D.E. & Flint, O.S. Jr Annotated list of the Neuroptera of Hispaniola, with new faunistic records of some species. J. Neuropterol., 3: Perkovsky, E.E., Zosimovich, V.Yu & Vlaskin, A.Yu Rovno amber insects: first results of analysis. Russian Entomol. J., 12: Perrichot, V Early Cretaceous amber from south-western France: insight into the Mesozoic litter fauna. Geol. Acta, 2: Perrichot, V Environnements paraliques à amber et à végétaux du Crétacé Nord-Aquitain (Charentes, Sud-Ouest de la France. Mém. Géosci. Rennes, 118: Petrunkevitch, A A synonymic index-catalogue of spiders of North, Central and South America with all adjacent islands, Greenland, Bermuda, West Indies, Terra del Fuego, Galapagos, etc. Bull. Amer. Mus. Nat. Hist., 29: Petrunkevitch, A The Antillean spider fauna a study in geographic isolation. Science, 68: 650. Petrunkevitch, A A study of amber spiders. Trans. Connect. Acad. Arts Sci., 34: Pls I LXIX. Petrunkevitch, A Chiapas amber spiders. Uni. Calif. Publ. Entomol., 31: Petrunkevitch, A Chiapas amber spiders, 2. Uni. Calif. Publ. Entomol., 63: Piel, W.H The systematics of neotropical orb-weaving spiders in the genus Metepeira (Araneae, Araneidae). Bull. Mus. Comp. Zool., 157: Pike, E.M Amber taphonomy and collecting biases. Palaios, 8: Pike, E.M Historical changes in insect community structure as indicated by hexapods of Upper Cretaceous Alberta (Grassy Lake) amber. Can. Entomol., 126: Platnick, N.I The world spider catalogue (version 8.5). Online at, spiders/catalog/intro2.html. Platnick, N.I. & Nelson, G A method of analysis for historical biogeography. Syst. Zool., 27: Platnick, N.I. & Penney, D A revision of the widespread spider genus Zimiris (Araneae, Prodidomidae). 165

27 174 physical properties of fluids 133 Pisauridae 41, 45, 63, 106, 107, 138, 140, 141 Plio-Pleistocene cooling/glaciations 142 Prodidomidae 41, 46, 51, 53, 55, 61, 120, 121, 138, 140, 141, 144, 150 Pseudochiridiidae 155 pseudoscorpions 11, 13, 14, redeposition of amber 26 ricinuleids 13, 14 Russian amber 16, 38 Salticidae 19, 23, 40, 41, 47, 50, 53, 59, 106, 108, 125, 127, 128, 131, 134, 135, 137, , 145 Samoidae 154 schizomids 13, 14, 152 scorpions 13, 14, 153, 155 Scutoverticidae 154 Scytodidae 42, 48, 50, 53, 59, 72, 73, 138, 140, 141, 150 Segestriidae 43, 53, 59, 78, 79, 138, 140, 141 Selenopidae 46, 53, 59, 122, 137, 138, 140, 141 sesquiterpenes 26, 27 Sicariidae 42, 50, 59, 71 73, 138, 140, 141 size of spider inclusions , 139 Smarididae 154 solifuges 13, 14, 153, 155 solubility of amber 26, 34 South American amber 19, 39 Spanish amber 16, 19, 34 Sparassidae 47, 53, 59, 63, 120, 122, 124, 138, 140, 141, 145 spider family richness spider insect co-radiations 19 Sternophoridae 155 Symphytognathidae 41, 44, 57, 94, 95, 138, 140, 141, 144, 150 synanthropic spiders 14, 75, 76, 84, 93, 94, 120, 122, 149 syninclusions 11, 131 taphonomy 11, 90, 130, 131, 133, 137, 139 terpenoid compounds 10, 26, 27 Tetrablemmidae 43, 50, 51, 53, 57, 78, 134, 138, 140, 141, 145, 150 Tetragnathidae 40, 41, 44, 53, 64, 100, 101, 134, , 145, 146 Theraphosidae 15, 42, 52, 55, 69, 138, 140, 141, 146 Theridiidae 15, 41, 43, 50, 51, 53, 55, 57, 64, 82, 89, 90, 94, 98, 100, 134, 135, , 150 Theridiosomatidae 40, 44, 51, 53, 55, 64, 94, 134, 138, 140, 141 Thomisidae 47, 53, 53, 59, 124, 125, 138, 140, 141 Triassic spiders 17 trigonotarbids 13, 14 Trochanteriidae 46, 61, 118, 119, 120, 138, 140, 141 Trypochthonidae 154 Ukranian amber 16, 42 Uloboridae 43, 51, 53, 57, 87, 134, 138, 140, 141, 150 uropygids 13, 14, 152 vicariance 25, 142, 145, 146, 149 viscosity (of resin) 27, 132, 133, 137