1998. The Journal of Arachnology 26 :120-123

RESEARCH NOTE

NOTES ON THE SYSTEMATICS OF THE LITTLE KNOWN THERAPHOSID HEMIRRHAGUS CERVINUS, WITH A DESCRIPTION OF A NEW TYPE OF

The presence of urticating hairs as a taran- Hemirrhagus cervinus (Simon 1891) has a tula defense mechanism is so far restricted to distinct pad of urticating hairs on the dorsal the New World Theraphosidae . The irritation surface of the abdomen . Scanning electron mi- caused by these hairs has been known since croscopy revealed that they differ in mor- Bates (1863) but not formally characterized phology and arrangement from known types until Cooke et al. (1972) described four types of theraphosid urticating hairs . H. cervinus, of abdominal urticating hairs . Marshall & the type species of the , is only known Uetz (1990) described a fifth type of urticating from the holotype specimen . The genus has a hair from Ephebopus sp. which is found on controversial systematic position . Raven the prolateral surface of palpal femur, rather (1985) considered it as a Theraphosidae in- than the abdomen. The defensive behavior in- certae sedis . Smith (1994) recommended sus- volved in the release of abdominal urticating pending the genus because he thought the type hairs was studied in detail by Perez-Miles & lost. Only The International Commission on Prandi (1991) in the Phrixotri- Zoological Nomenclature has power to sup- chus mollicoma (Ausserer 1875) (previously press a name, ICZN art . 79. The female ho- Grammostola mollicoma) and by Bertani & lotype of Hemirragus cervinus, from Mexico, Marques (1995/96) in several species of Ther- deposited at the Museum National d'Histoire aphosinae and . Naturelle de Paris, is available and was ex- Urticating hairs and the associated releasing amined . To minimize the damage to the type, behavior was used by Perez-Miles (1992, a small area (less than 1 mm') of the dorsal 1995) and Perez-Miles et al. (1996) to eluci- surface of the abdomen bearing hairs was re- date phylogenetic relationships in the Thera- moved for study by SEM and some loose phosinae and related groups . Since defensive hairs were observed by light microscopy . Oth- abdominal movements are present only in the er characters were studied by a stereoscopic Aviculariinae and Theraphosinae, this was in- microscope, drawings were made with the aid terpreted as a synapomorphy, supporting their of a camera lucida . Considering the size and sister group relationship (Perez-Miles et al . morphology of abdominal urticating hairs in 1996) . However, Theraphosinae shed small H. cervinus, the releasing mechanism seems urticating hairs while Aviculariinae (except to be as in Theraphosinae (hair flicking-air- Ephebopus Simon 1892) employ larger urti- borne dispersal) . The presence of such urti- cating hairs by direct contact with the poten- cating hairs lead me to propose the placement tial predator. Considering the differences in of H. cervinus in the Theraphosinae . morphology and release mechanisms of the Abdominal hair morphology .-Scanning urticating hairs in the Aviculariinae versus the electron micrographs reveal straight, stout fu- Theraphosinae, their independent acquisition siform barbed hairs, acutely pointed at both was proposed (Perez-Miles 1995 ; Perez-Miles ends (Figs . 1-4). The length of these hairs is et al., 1996 ; Bertani & Marques 1995/96). The 0.315 ± 0 .021 mm (mean ± 1 SD, n = 30 different location of urticating hairs of Ephe- hairs) . Hair barbs are subtriangular but not ho- bopus also suggests their independent evolu- mogeneous in size, and slightly longer on the tion (Bertani & Marques 1995/96) . distal region. Barbs, present on the proximal 120 PEREZ-MILES-DESCRIPTION OF HEMIRRHAGUS 1 21

I

Figures 1, 2-Scanning electron micrographs of Figures 3, 4-Scanning electron micrographs of abdominal hairs of Hemirrhagus cervinus . 1, Struc- abdominal hairs of Hemirrhagus cervinus . 3, Close ture of the urticating hairs, hair field partially ablat- up of the cuticle showing the basal part of attached ed showing arrangement of the hairs (Scale = 0 .2 hairs and ablated hair sockets (Scale = 0 .2 mm) ; 4, mm) ; 2, Close up of the distal portion of an urti- Close up of the basal end of some loose urticating cating hair (Scale = 0 .02 mm) . hairs, showing the acute basal tip out of the socket (Scale = 0.02 mm) .

80% of the hair, are obliquitous with respect to the hair axis (40°), and orientated with their Holotype .-Female from Mexico, without tips towards the hair distal end (Fig . 2) . A locality data, deposited in Museum National slight inflection of approximately 5-10° was d'Histoire Naturelle, Paris, #756, examined . observed in the axis of some hairs, near the Diagnosis .-Differs from other Theraphos- proximal bases . idae by the presence of urticating hairs of the Abdominal hairs are attached in distinctive type described here (Figs . 1-4), in the coxae insertion sockets on the cuticle (Fig . 3) . The with a retrolateral-ventral heel (Fig . 5), and in sockets are cylindrical and the bases of the the morphology of the spermathecae (Fig . 6) . hairs are held in them until the hair is released . It differs from the Aviculariinae in the differ- The region of the hair that is located in the ent morphology of the scopulae (not laterally socket is not barbed and has a very sharp tip extended), scopular hairs (not widely spatu- (Fig. 4) . late), and urticating hairs . Comments .-Morphological and position- SYSTEMATICS al evidence presented here suggests that the Hemirrhagus cervinus (Simon 1891) defensive function and urticating effect of ab- dominal hairs of H. cervinus is similar to Cratorrhagus cervinus Simon 1891 :330; E Pickard- Cambridge 1899 :41 ; Hemirrhagus cervinus those found in other New World theraphosids . Simon 1903 :926 ; Strand 1907 :16, 1912 :175 ; Pe- Hair flicking seems likely to be the shedding trunkevitch 1911 :71, 1928 :78 ; Roewer 1942 :231 ; mechanism, considering their small size Raven 1985 :116; Smith 1994 :185. (0.315 mm, length) and their presumed low 122 THE JOURNAL OF ARACHNOLOGY

cervinus is morphologically similar to those of Ephebopus, but shorter. Also the socket is narrower and the main difference is their lo- cation on the body. For these reasons abdom- inal hairs of Hemirrhagus cannot be consid- ered as homologous to the palpal hairs of Ephebopus . These facts suggest that the urti- eating hairs found in Hemirrhagus are of a 6th, previously undescribed, type . Hemirrhagus, traditionally placed in Is- chnocolinae (Ischnocoleae of Simon 1903, in Ischnocolinae by Roewer 1942), and was con- sidered as Theraphosidae incertae sedis by Raven (1985) . The examination of the type and the study of some features lead me to pro- pose the placing of Hemirrhagus in the Ther- aphosinae . Hemirrhagus cervinus has abdominal urti- eating hairs, which are,only found in Thera- phosinae and Aviculariinae . H. cervinus does not have wide scopulae, lacks spatulate scop- ula hairs, and lacks the heavy, contact urticat- ing hairs as they occur in the Aviculariinae . Also, leg spines are absent or scarce in Avi- 6 culariinae, but are present in H. cervinus . All these facts argue against its inclusion in the Figures 5, 6-Structures of the holotype of Hem- Aviculariinae . Perez-Miles et al. (1996) pro- irrhagus cervinus . 5, Ventral view of labium, ster- posed the abdominal defensive movements as num and left coxae showing the retrolateral projec- synapomorphic of Aviculariinae plus Thera- tion on coxae of all legs (arrow shows this feature phosinae. Since H. cervinus is only known only on coxa of fourth leg) ; 6, Spermathecae, ven- from the type, this could not be tested . How- tral view. ever, the presence of abdominal urticating hairs suggests such behavior. If this hypothe- weight in comparison with larger (0 .5-1 .5 sis is correct then its inclusion in Theraphos- mm, length), heavier urticating hairs from ar- inae seems to be the best placement, at least . The spermathecal boreal A .viculariinae (Bertani & Marques until the male is described morphology is compatible with the proposed 1995/96) which rely on contact, not airborne placement. Also the coxae of legs with retro- dispersal. lateral projection indicated by Smith (1994) is Both distal and basal ends of the hair are here confirmed in the type, and interpreted as sharp, but the orientation of the barbs suggests a generic apomorphy . that the penetration tip is the basal end . The orientation of the barbs and the socket mor- ACKNOWLEDGEMENTS phology of type V hairs (from fig. 2 of Mar- I am grateful with Dr. Christine Rollard shall & Uetz 1990) led me to assume that the (MHNP) for the loan of the specimen and penetrating end lies proximally, which agrees with Lie. Patricia Sarmiento (UNLP) for the with Bertani & Marques (1995/96) . A proxi- SEM operation . Thanks to EG. Costa and mal position of the penetrating tip was also R.M. Capocasale for the critical reading of the indicated for hairs of type II (Cooke et al . manuscript . I acknowledge S . Marshall, R. 1972 ; Bertani & Marques 1995/96) ; but con- Wolff, J. Berry and P. Sierwald for their valu- sidering the differences in morphology, ar- able cricticisms and suggestions . rangement, and shedding mechanisms with LITERATURE CITED Hemirrhagus, that similarity is interpreted as Bates, H .W. 1863 . The Naturalist on the river Am- nonhomologous . azons. Vol. 1, John Murray, London, Pp. 160- The type of abdominal hairs found on H. 162.

PEREZ-MILES-DESCRIPTION OF HEMIRRHAGUS 123

Bertani, R . & O.A.V. Marques . 1995/9 6. Defensive Perez-Miles, E, S .M. Lucas, Pl. da Silva, Jr. & R . behaviors in Mygalomorph : release of ur- Bertani. 1996. Systematic revision and cladistic ticating hairs by some Aviculariinae (Araneae, analysis of Theraphosinae (Araneae : Theraphos- Theraphosidae). Zool . Anz., 234 :161-165. idae) . Mygalomorph, 1 :33-66. Cooke, J.A.L., VD. Roth & EH. Miller. 1972. The Perez-Miles, E & L. Prandi. 1991 . El comporta- urticating hairs of theraphosid spiders . American miento de envision de pelos urticantes en Gram- Mus. Nov., 2498 :1-43. mostola mollicoma (Araneae, Theraphosidae) : un Intern . Comm . Zool . Nomen .. 1985. Intern. Code analisis experimental . Bol. Soc . Zool . Uruguay, Zoo]. Nomen ., 3rd ed., Intern . Trust Zool . No- 6:47-53 . men., London, 338 pp . Raven, R.J. 1985. The spider infraorder Mygalo- Lucas, S., PI. da Silva, Jr. & R. Bertani . 1991 . The morphae (Araneae) : cladistics and systematics . genus Ephebopus Simon, 1892. Description of Bull. American Mus. Nat. Hist., 182 :1-180. the male of Ephebopus murinus (Walckenaer), Smith, A .W. 1994. spiders, Vol . 2. Ta- 1837. (Araneae, Theraphosidae, Aviculariinae) . rantulas of the U .S.A. and Mexico. Fitzgerald Spixiana, 14(3) :245-248. Publ., London, 196 pp . Marshall, S .D. & G.W. Uetz. 1990. The pedipalpal brush of Ephebopus sp. (Araneae, Theraphosi- Fernando Perez-Miles : Division Zoologia dae): Evidence of a new site for urticating hairs . Experimental, Instituto de Investigaciones Bull. British Arachnol . Soc ., 8(4):122-124 . Biologicas Clemente Estable, Av. Italia Perez-Miles, E 1992. Analisis cladistico preliminar 3318, 11600 Montevideo, Uruguay ; and de la subfamilia Theraphosinae (Araneae, Ther- Seccion Entomologia, Facultad de Ciencias, aphosidae). Bol. Soc . Zool . Uruguay, 7 :11-12. T Narvaja 1674, 11200 Montevideo, Uru- Perez-Miles, E 1995. Revision y analisis cladistico guay de la subfamilia Theraphosinae (Araneae, My- galomorphae, Theraphosidae) . Ph.D. thesis, Manuscript received 15 May 1996, accepted 5 Universidad de la Republica, Montevideo . March 1997.