Frederick A. Coyle.
The Mygalomorph Spider Genus Atypoides (Araneae: Antrodiaetidae).
Psyche 75:157-194, 1968.

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THE MYGALOMORPH SPIDER GENUS ATYPOIDES
(ARANEAE : ANTRODIAETIDAE) *
BY FREDERICK A. COYLE
Biological Laboratories, Harvard University INTRODUCTION
The genus At~poidcs belongs to the mygalomorph spider family Antrodiaetidae, the remainder of which I am presently revising, and is closely related to the much larger genus Antrodiaetus. Atypoides was established by 0. P.-Cambridge ( 1883) with his description of Atypoides riversi. Since then two additional species have been discovered. The genus is solely Nearctic and has a markedly dis- junct continental distribution, with two species in northern Cali- fornia and southern Oregon and one in southern Illinois and Missouri.
Like the other species of antrodiaetids, those of Atypoides live in tubular silk-lined burrows in the gound and nocturnally capture prey which come within reach of the burrow entrance. In the present revision Atypoides riversi is redescribed, the two new species are described, and the geographic variation of each species is analyzed. Information on the ecology, life history, and behavior of these species will be included in a future paper treating the entire family.
Acknowledgements.
I am indebted to Dr. H. W. Levi of the
Museum of Comparative Zoology for encouragement and advice and to Dr. W. J. Gertsch of the American Museum of Natural History for his suggestion that I study this genus and for the large loan of A.M.N.H. material, much of which he himself has collected. Mr. J. A. Beatty, Mr. Patrick Craig, the California Academy of Sciences, and the University of Kansas have each loaned specimens. I am grateful to Prof. Varley of the University Museum of Oxford University, England, for the loan of the six syntypes of Atypoides riversi. Dr. W. H. Bossert of Harvard wrote the computer pro- grams employed in the analysis of variation. My wife, Judy, con- structed the distribution maps and helped cheerily with several other portions of the research. A National Science Foundation Graduate Fellowship and grants from the Evolutionary Biology Committee of Harvard University supported my field work during the summers of 1966 and 1967.
Public Health Service Research Grant AI-01944 to Dr. Levi helped defray some expenses. Publication is supported "Manuscript received by the editor June 12, 1968 157




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by a grant from the Evolutionary Biology Committee of the Depart- ment of Biology, Harvard University.
METHODS
Statistical methods. An analysis of variation of quantitative char- acters was performed on the three species of Awides with two aims in mind: to discover quantitative characters of value in dis- tinguishing between species of antrodiaetids, and to investigate in a preliminary manner the geographic variation within each species. There is greater need for such studies in mvgalomorph spider tax- onomy than in many araneomorph groups because of the lack of diagnostically useful complex external genitalia in the former. How- ever two major difficulties confront anyone attempting to study variation in mygalomorph species : the difficulty of collecting samples of adequate size, and the more difficult problem of achieving age homogeneity within samples of females. Antrodiaetid females (and females of other mygalomorph species) live and continue to molt fo1- one to several years after becoming sexually mature. No external structure or characteristic gross difference in seminal receptacle form has been found which indicates when a female has reached sexual maturity or what instar an adult female may be. In the present study a female specimen was included in a popu- lation sample only if it had a longer carapace than the smallest reproductively active female (with an abdomen swollen with eggs or with brood in her burrow) from the entire sample of specimens of that species. An exception was made for A. riversi where the smallest of a large number of reproductively active females collected in the coastal population was considerably larger than the single reproductively active Siesran population sample female. The low size limit for each of these two major population samples was there- fore determined by the smallest reproductively active female within it. The non-reproductively active females included in a sample rep- resent first adult instar females collected in the summer just before or after their initial mating, later adult instar females without broods, and probably an occasional immature female. It is likely that the small number of reproductively active females (one each) collected in the Sierra11 samples of A. riversi and in Atyftoides gutschi result in samples somewhat biased toward the upper end of the actual adult female body size range. Tiventjy-one measurements and 13 meristic characters were re- corded for 60 males and 159 females of the three species. (The
abbreviations and definitions for these measurements and meristic



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19681 Code - Spider Genus Atypoides I59
characters are given in the appendix at the end of this paper.) These data were analyzed with the aid of a 709.1 IBM computer at the Harvard Computer Center. The computer program, written in Fortran 11, calculated the mean and standard deviation of each measurement, meristic character, and each of 44 different ratios formed from these for each population sample of each sex and for certain groupings of samples plus individual specimens into infra- specific or species units. The program then compared these samples and groupings pairwise in all desired combinations giving for each character for each con~parison a value of the distinctness of the two samples. This value, called the "distance", is equal to the difference between the mean of each of the two samples divided by the sum of their standard deviations. This enabled me to quickly select those characters of greatest diagnostic value, those characters which show the most marked geographic variation, and those infraspecific samples that were most divergent.
As will be evident in the species diagnoses and Tables I and 11, many of the measurements, counts and ratios are diagnostically use- ful in this genus.
Several measurements and counts which are not diagnostically useful are included in the tables for their descriptive value or because they are diagnostically important in Antrodiaetus, a genus in which the species are often morphologically much more similar to one another than is the case in Atypoidr~~ The analysis
of geographic variation is considered preliminary because of the small sample sizes and the lack of more samples from important parts of each species' distributional range. Each of the localities from which a population sample of A. rivers' or A. gertschi was obtained is labeled on Map I and identi- fied in the locality records by a capital letter. These letters will be used throughout the text when referring to a particular sample or locality. The population sample sizes are indicated in the Dice-Leraas diagrams and the species sample sizes are given in Tables I and 11. Measurements. All measurements were performed by myself with the same binocular stereomicroscope and eyepiece micrometer scale. A series of three specimens was remeasured for each char- acter five times during the course of the study and indicated that the measurements were accurate to one micrometer unit for each of the four different powers of magnification used. One micrometer unit had the following value for the following characters: 0.0753 mm for CL; 0.0377 mm for CW, SL, SW, and all leg and pedipalp segment lengths; 0.0182 mm for PTT; and 0.0092 mm for CAT and all eye measurements.




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I 60 Psyche [June
Illustrations.
Drawings were made with the aid of a squared grid reticle placed in an eyepiece of a binocular stereomicroscope. Illustrations of female structures are made from reproductively active specimens or specimens much larger than the smallest repro- ductively active one within that species sample. Descriptions.
Each description is a composite of all the adult material at hand with close attention given to the type specimen in order to point out any characters for which it is peculiar. Colors are described in strong illumination under the low power of the stereomi- croscope from a series of specimens which have been dead in 80% ethanol for six months to two years. Color changes in Atypoides appear to be minimal within this time period. Records. Only material that has been personally examined is included within the records section. Numbers of immature specimens are not recorded; a lack of or $ symbols means that only im- matures were collected at that particular locality. The following abbreviations are used for the names of the more frequently cited collectors : FAC - F. A. Coyle, JWG - J. W. Gertsch, WJG - W. J. Gertsch, WI - W. Ivie, VR - V. Roth. Morphological terminology. Female genitalia: In Atypoides the sperm storage diverticulum opens into the uterus just as the latter opens exteriorly at the epigastric furrow (Figs. 78, 79). The epigas- tric furrow is between a large anterior lip and a smaller posterior lip. On the posterior face of the anterior lip is a more heavily sclerotized area which frames and extends inward through the transverse slit-like opening into the sperm storage diverticulum. This thickened cuticle also forms the floor of a rather large chamber which will be called the bursa copulatrix. This thickened floor often forms paired shallow depressions or ill-defined pockets which possibly function in the positioning of the male palpal sclerites. Four trans- parent ducts leading from the bases of the semmal receptacles open into the very weakly sclerotized roof of the bursa copulatrix. The four seminal receptacles are arranged transversely in a single row, and are thick-walled and heavily sclerotized except distally where they are capped by a rounded thin-walled transparent bulb. The proximal narrow part of the heavily sclerotized portion will be called the stalk, and the distal expanded part will be termed the bowl EXPLANATION OF PLATE 7
Figs. 1-9. Carapace and chelicerae (lateral and dorsal views). 1-3. A. riversi. 1-2. 9 from C. 3. 8 lectotype. 4-6. A. hadros. 4-5. $ paratype, from type locality. 6. $ holotype. 7-9. A. gertschi. 7-8. 9 paratype, from 0. 9. $ paratype, from 0.




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(Fig. 82). JIdc pdpu~: 111 Jfy#oid~s the cmductor is composed of two sclerites ( Fig. 57 ) , an inner cond~cior scirritc, which tapers and mntah~ the ~jnh/us distally, a d an otitcr cofidwior scIcrit~, which lies outside and cradles the inner coductor derite. ~lfacru- ~ m - : A 1a:gc thick sera, articdated in a well-dedoped socket, 1 sld call a wm-rtisrfa. This is equivalent 10 the "spine" of most qider taxonomkts. *An ~n~iforui macroseta is one wl~ich tapers absuptl!, at its tem~ind end and is therefow rigid for its entire length. +An ~fimufitr macroseta is one which tapers gradually and is therefo~e 'cry sIe11dw distally and easily bent. The hir most lateral n1ac1-metae on the ventral surface of the tibia in Figure 71 are enci- form, the two median ones attenuate. 8fiimrrrtj-: The abbrtviations AL3 P31, and PL will be used to designate the following spinnerets re-pectivel>+ : anterior lateral, posterior median, and posterior lateral. SYSTEMATICS
A tyfioidcs 0. P.-Cambridge
Aiypoidcs 0. P.-Cambridge, 1883, Pmc. 2001. Sw. Lond., pa 354. [Type species by monotypy: A. riwrrsi 0. PXarnbridge, op. fit., p. 355, PI. 36, fig. 2.1
- Simon, 1884, Bull. SOC. 2001. Fr., 9: 3IJ1 314, 316. - Simony 1890, Actes Soc. Linn. Bord., 44: 307, 309. -Simon, 1892, Histoire Naturelie des Araignees, pp, 193-195, fig, 138. -Smith, 1908, Ann, Ent, SOC. Amer., I(+) : 210, 211, 231. - Cornstock, 1912, The Spider Book, pp. 230, 249, 250; 09. cd., rev. ed., 1940, pp. 2371 23L -Gerte.ch, 1949, American Spiders, pp. 127, 130,
1311 265. - BonneG 195& Bibliographia
Araneorum, 2: 811.
DESCKIFTIUN. Cwafinct: Pars cephdica elevated above pars thoracica. Thoracic groove longitudinal. Eyes: Situated on slightly raised area (more prominent in males) which is steeply inclined an- teriorly. ALE largest, forming transverse or slightly prmurved row with AXIE. Lareral limits of eye group formed by FLE. PME
widely separated, close to their respective PLE. Stwmmz - h&um:
4 pairs of sigilla; ant. pair large, just behind labium, often indis- tinct; post. pair larger than second or third pair. Cheiicerae: Robust with strong raste1lar spines in female. Single row of large teeth (mm-oteeth) on nwsal side of dosed fang; much sm&r teeth (mi- croteeth} on ectal side of post, porrion of macrotooth row. Large apophysis projects anteriorly and dorsally from adult male chtlicera; dense brush of large setae dorsaEy near distal end of apophysis. Pedi#al#~: Coxd endite quite mall. Patella of male much shorter than tibia; tibia swollen, Ouxer conductor scle~ite of male pdpus wide, serrated on external surfacey and curved in cross section so that it partially mvelopm inner conductor dcrite. Distd portion of inner conductor scierite heavily sclerocized, narrow, and envelops



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19681 Coyle - Spider Genus A typoides 163 distal portion of embolus. Legs: Legs I and IV longer than legs' I1 or 111. Row of 9-26 trichobothria on dorsal surface of metatarsus IV of female. Abdomen : 1-3 sclerotized areas ( tergites) anteriorly on abdominal dorsum. Spinnerets: 3 pairs. AL unsegmented and reduced. PM unsegmented with functional spigots distally. PL 3-segmented with functional spigots on second and third articles. Seminal receptacles: 4 receptacles; distinct sclerotized stalks. DIAGNOSIS.
Atypoides may be distinguished from the genus An- trodiaetus by each of the following two characters: I) three pairs of spinnerets (AL may be extremely reduced and difficult to spot in some specimens of A. g-ertschi). 2) Male with cheliceral apophy- sis. The much wider outer conductor sclerite of the male palpus of Atypoides allows separation of this genus from all known North American species of Antrodiaetus.
Atypoides may be distinguished from AZiaty~us by each of the following characters : I ) AL spinnerets unsegmented. 2) Male with cheliceral apophysis. 3) Patella of male pedipalp not greatly don- gated. 4) Thoracic groove longitudinal, 5 ) Burrow entrance struc- ture consists of a collapsible collar or a stiffened turret. 6) At
least 8 or g trichobothria on the dorsal surface of metatarsus IV of the female. Also the structure of the male palpus in each of these two genera is distinct.
DISCUSSION. Atypoides is closely related to Antrodiaetus. Both of these genera are much less closely related to Aliat~~pus. One of the two dia,gnostic structures separating the former two genera - AL spinnerets - is a degenerating character, and by itself would be a poor excuse for maintaining At~poides as a separate genus. On the other hand, the cheliceral apophysis is well developed in all Atypoides males; it does not seem to be in the process of degenerating. How-
ever, it is possible that in some member (or members) of an earlier Atypoides-Antrodiuetus stock a cheliceral apophysis could have been quickly lost and its function of holding the female during mating taken over by the first legs. A consideration of the evolution of Atypoides will await the revision and similar consideration of the other antrodiaetid genera. At present it seems desirable to maintain the generic status of Atypoides, since it can be rather easily char- acterized and distinguished from Anirodiaetus, Incorrect pZuce7nent.
Atypoides culifornica Banks = Aliat~pus
californicus (Banks). Banks (1896) described this species fsom an immature male specimen collected at Black Mountain, Santa Clara Co,, California. . Smith . ( 1908) discovered the adult male of this



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species and appropriately described a new genus (Aliatypus) for its placement.
Key to the Species of Atypoidef
Males
I. Width of sternum equal to or slightly less than its length (not including labium) (Fig. 37). Tibia I with prominent macro- setae clustered near proximal end on prolateral surface and retrolaieral aspect of ventral surface; often I or 2 macrosetae near middle on ventral &-face; no macrosetae at distal end of ventral surface (Figs. 71-73). Eastern U. S. (Illinois and ........................................................................ Missouri) hadros
Sternum (not including labium) clearly longer than wide (Figs. 35> 39). Tibia, I with macrosetae present in ill-defined ventral and prolateral rows which extend most of its length; usually I to 3 macrosetae present ventrally at distal end (Figs. 68, 69, ........ 74, 76, 77). Western U. S. (Oregon and California) 2
2. Palpal tibia not cylindrical, diameter in lateral view much greater at 113 the distance from ~roximal to distal end than nea,r distal end (Figs. 10-1 3). Metatarsus I with I to 4 macro- setae on ventral susface, usually clustered at distal end (Figs. 68-70). AL spinnerets 113 or more as long as PM (Fig. 31). ....................
Abdomen purplish grey or purplish brown
riversi
Palpal tibia swollen in cylindrical form of nearly equal diameter for most of its length (Fig. 15). Metatarsus I with ill-defined ventral longitudinal row,s of macrosetae extending nearly its entire length (Figs. 75-77). AL spinneret 115 or less (may be extremely reduced and difficult to spot) as long as PM (Fig. 30). Abdomen pale grayish yellow or pale gray ............ .......................................................................................... gertschi Females
I. Sternum (not including labium) as wide as long (Fig. 38). Fewer than 13 enciform macrosetae on metatarsus I. Fewer than 7 microteeth per chelicera (Fig. 43). Wide sets,-less area on ectal side of anterior portion of cheliceral macrotooth row, Eastern U. S. (Illinois and Missouri) ........................ hadrox Sternum (not including labium) clearly longer than wide (Figs. 36, 40). More than 13 enciform macrosetae on metatarsus I. Usually more tha.n 7 microteeth per chelicera (Figs. 4.1, 42). Seta-less area on ectal side of anterior portion of cheliceral macrotooth row very narrow or absent. Western U. S. (Ore- gon and California) .............................................................. 2



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19681 Coyle - Spider Genus A typoides 165 2, AL spinnerets 113 or more as long as PM spinnerets (Fig. 31). Abdomen purplish gray or purplish brown, Seminal receptacles hea,vily sclerotized with well developed bowl (Figs. 80-86). ............................................ IVA4L/IA,fL = I -03-1 -20
riversi
AL spinnerets 116 or less (may be extremely reduced and difficult to spot) as long as PhI spinnerets (Fig. 30). Abdomen pale grayish yellow or pale gray. Seminal receptacles less heavily sclerotized with bowl weakly developed to absent (Figs. goL ...............................
94.) IVhIL/IML = 1.34-1.45 gerischi
Aiypoides r-iversi 0. P.-Cambridge
Figures 1-3, 10-13, 16, 17, 22-29, 31, 33, 34, 39, 40, 42, 44, 45, 47-49, 53-56, 68-70, 80-86. Map I.
Atypoides riversii 0. P.-Cambridge, 1883, Proc 2001. SOC. Lond., p. 355, pl. 36, fig. 2. [Three male and three female syntypes from Berkeley, California; collected by J. J. Rivers; in the University Museum, Oxford University, England; all examined. (One of these males is here des- ignated the lectotype and the other five specimens paralectotypes and are so labeled.)] -Roewer, 1942, Katalog der Araneae, 1: 189. Atypo:dcs riversi: Simon, 1884, Bull. SOC. 2001, Fr., 9: 316. -Simon, 1892, Histoire Naturelle des Araignees, 1: 195, fig. 138. - Smith, 1908, Ann. Ent. SOC. Amer., l(4) : 209, 210, 229, PI. 15, figs. 7, 8, 9, PI. 19, fig. 2, p1. 20, figs. 3, 4. -Cornstock, 1912, The Spider Book, p. 250; o$. c..t., rev. ed., 1940, p. 238. - Gertsch, 1949, American Spiders, p. 131, - Bonnet, 1958, Bibliographia Araneorum, 2: 811. COMATENTS ON ORIGINAL DESCRIPTION. In his description and illustrations of A. riversi, 0. P.-Cambridge (1883) failed to in- dicate the presence of a conductor on the male palpus. This misled subsequent authors (Smith, I 908, and Comstock, I g I 2, I 940) , who used the lack of a conductor as a diagnostic character for the genus. What may have misled Cambridge is that in the male syntypes the embolus has slid distally within the inner conductor sclerite, and the inner conductor sclerite has also slid distally and rotated within the outer conductor sclerite to extend far beyond it (Figs. 54, 55). A few of the A. riverri males which I have collected have similarly "flexed" palpi. One should be aware of the possibility of such flexion when identifying male antrodiaetids.
The lectotype and paralectotypes have changed color considerably in the 85 years since their description. The greenish hues have dis- appeared so that the colors are dull light oranges and orange browns. DESCRIPTION.
See Tables I, 11, and I11 which contain measure- ments, meristic characters, and diagnostic ratios for a sample of the species and for the lectotype.




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19681 CoyZe -- Spider Genus Atypoides 167 fifale. Carapace:
(Figs. 3, I 7). Elongate oval. Thoracic groove narrow for entire length; center of thoracic groove clearly less than 2/3 distance from ant. to post. border of carapace. Setae present only near edge of carapace and around eye group, Pars cephalica weaklv elevated; highest at ocular prot~lberance. Height of clypeus at ALE about equal to vertical diam. of ALE. Diam. of AME 314. to 2 times their distance apart. Sternum: (Fig. 39). Elongate. 3 post. pairs of sigilla circular to oval. Chelicerae: (Figs. 3, 47-49). Apophysis relatively slender, strongly curved downward near distal end, Apophyseal setae all attenuate, post. ones stronger than ant. ones. Pedipalps: (Figs. 10-13, 53-56). Greatest diam. of tibia is about 113 the distance from proximal to distal end; tapers to much smaller diam. distally. Outer conductor sclerite of palpus heavily sclerotized, relatively short and wide, serrations strong; tip very broad and nearly straight across. Inner conductor sclerite extends far beyond end of outer conductor sclerite in unflexed condition; distally curved and grad~~ally tapering to rather sharp tip. Leg I: (Figs. 68-70). Tibia usually with a prolateral row and an ill-defined double or single row of macrosetae on the retrolateral aspect of the ventral surface extending most of its length; I to 3 (very rarely 0) macrosetae ventrally at very distal end. Tibia nearly straight and cylindrical, cuxing slightly downward at distal end. Metatarsus with I to 3 macrosetae ventrally at very distal end, rarely with one on prolateral surface 113 of way from proximal to distal end. Sfeta-
tarsus long and slender, tapering slightly toward distal end, nearly straight in lateral view, slightly bowed in ventral view with prolateral surface concave. Abdou~en: Large, median, longitudinal, tri-nodal dark pattern.
Large tergite in central node. No other tergites. Spin- nerets: ( Fig. 3 I ) . AL only weakly sclerotized terminally with spigot at tip, or scIerotized terminally without spigot. AL 1/3 to 112 as long as P&I. PA1 slightly expanded to unexpanded distally; maxi- mum diam. from 114 to slightly over 1/3 length. CoZoration: Pars thoracica yellowish gray to pale greenish brown. Pars cephalica pale greenish brown posteriorly, becoming brown to reddish brown an- EXPLANATION OF PLATE 8
Figs. 10-15. Male pedipalp (retrolateral view of left pedipalp), 10-13. A. riwer~i. 10. from D. 11. Ie~totype~ 12. from I. 13. from G. 14. A, hadrox, holotype.
15. A. gertschi, paratype, from 0. [2.0 mm scale line for 10-151 Figs. 16-21. Eyes (dorsal view with lateral border of carapace hori- zontal). 16-17. A. riverxi. 16. 9 from C. 17. 8 paralectotype, from C. 18-19. A. hadros. 18. 9 paratype, from type locality. 19. 8 holotype. 20-21. A. gut~chi. 20. 9 paratype, from 0. 21. 8 holotype. r0.5 mm scale line for 16-21]




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Psyche
x A. gertschi
A. riversi
Map 1.
Distribution of Atypoide~ species.




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19681 Coyle - Sfiider Genus Atypoides 169 teriorly. Sternum slightly paler yellnwi~h gray than pars thosacica) labium and palpal coxae slightly darkei- than pass thoracica. Cheli- cerae reddish brown to dark brown. Palpal femur and patella and dorsal surface of leg I light greenish brown to reddish brown; palpal tibia much lighter. Rest of legs dorsally similar to pars thosacica) ventrally lighter. Abdomen dull purplish brown with many small