A NEW SPECIES AND A NEW SYNONYMY IN THE SPINY ORB-WEAVER SPIDER GENUS MICRATHENA (ARANEAE, ARANEIDAE)

2004·3.5 MB·English

by  Marcelo O Gonzaga

—
2004. The Journal of Arachnology 32:332-335
SHORT COMMUNICATION
A NEW SPECIES AND A NEW SYNONYMY IN THE
SPINY ORB-WEAVER SPIDER GENUS
MICRATHENA (ARANEAE, ARANEIDAE)
Marcelo O. Gonzaga: Pos-Graduagao em Ecologia, Departamento de Zoologia,
UNICAMP, Caixa Postal 6109, 13083-970, Campinas, SP, Brasil. E-mail:
[email protected]
Adalbert© J. Santos: Pos-Graduagao em Zoologia, Universidade de Sao Paulo.
Laboratorio de Artropodes, Institute Butantan, Av. Vital Brasil 1500, 05503-900,
Sao Paulo, SP, Brazil. E-mail: [email protected]
ABSTRACT. A new species, Micrathena ciciita, is described and illustrated based on females from
southeastern Brazil. Plectana degeeri Walckenaer is synonymized with M. plana (C.L. Koch), based upon
the original description.
Keywords: Micrathena, Brazil, South America, systematics, new species
The genus Micrathena Sundevall 1833 is a com- Levi (1985) and all measurements are in millime-
mon and conspicuous group of diurnal spiders en- ters.
demic to the Americas. They can be easily recog-
RESULTS
nized by their spiny abdomen, vertical orb-webs
with an open hub and their characteristic upside Micrathena cicuta new species
down position on the webs, with the abdomen in- Figs. 1-5
clined horizontally. They differfrom Gasteracantha
—
Sundevall 1833 by the shape of carapace and from Material examined. Holotype female, Volta
Chaetacis Simon 1895 by lacking spines or tuber- Redonda, Area de Relevante Interesse Ecologico
cles on the carapace behind the lateral eyes (Levi Floresta da Cicuta, 22°3LS 44°07'W, State of Rio
1985). The genus was revised by Levi (1985) and de Janeiro, Brasil, 18 February 2002, M.O. Gon-
comprises 104 species with a mostly Neotropical zaga (IBSP 36322). Paratype: 1 female, Resende,
distribution. Of these, 33 are known only from fe- District ofSerrinha do Alambari, 22°20'S 44°30'W,
males and except for two notes describing males of State of Rio de Janeiro, Brasil, E.F Ramos, 31
previously known species (Bonaldo 1990; Lise March 1996 (IBSP 27195). Other material exam-
1995) and the synonymy ofThaumastobella niourei ined: BRASIL: Sao Paulo: Salesopolis, Esta^ao
Mello-Leitao 1945 with Micrathena saccata (C.L. Biologica de Boraceia, May 2001, equipe BIOTA,
Kock 1836) (Scharff 1991), the systematics of the 1 9 (IBSP 39799); Cotia, Reserva Florestal de
genus has remained unaltered since Levi’s revision. Morro Grande, 26 March 2003, A. A. Nogueira et
In this paper we describe anew species,Micrath- ak, 1 9 (IBSP 39794), 4 9 (IBSP, 39795-39798);
ena cicuta, of the kirbyi group (as defined by Levi 15 9 (MZSP).
1985). This is the largest species group in this ge- Etymology. The specific name is a noun in ap-
nus and includes 45 species distributed from Cen- position taken—from the type locality.
tral America to southern South America. Addition- Diagnosis. Micrathena cicuta shares with Mi-
ally, we synonymize M. degeeri (Walckenaer 1842) crathena clypeata (Walckenaer 1805) a flat abdo-
with M. plana (C.L. Koch 1836), another member men with rounded sides, covered by several scler-
ofthe kirbyi group, based upon theoriginaldescrip- otized disks and minute granules and with one
tion. anterior pair of spines. It is distinguished by the
The specimens examined were deposited in the abdomen with 8 marginal pairs of black thorns (5
spider collection ofthe Instituto Butantan, Sao Pau- in M. clypeata) and by the absence of dimples on
lo (IBSP) and Museu de Zoologia, Universidade de the carapace (Fig. 1). The epigynum differs by the
Sao Paulo (MZSP). The description format follows narrower lateral lobes and median plate in ventral
332
—
GONZAGA & SANTOS—NEW SPECIES OF MICRATHENA 333
Figures 1-4. Micrathena cicuta new species. 1. Female habitus, dorsal view. 2. Female epigynum,
posterior view. 3. Ventral. 4. Lateral. Scale bars, 1 = 1.00 mm; 2-4 = 0.50 mm.
—
and posterior views (Figs. 2, 3), the anteriorly Distribution. Known only from southeastern
notchedtransverse barwith alongerandposteriorly Brazil. This species seems to be closely related to
directed lobe (Fig. 3) and by the rounded bulge in M. clypeata, which occurs in Panama, northern
lateral view (Fi—g. 4). South America and the Amazon Basin (Fig. 5).
Description. Male.- Unknown. These two species display a disjunct distribution,
Female (holotype): Carapace orange, with a high occurring in tropical rainforest areas separated by
thoracic region. Clypeus, chelicerae, labium, en- central and northeastern Brazilian savanna vegeta-
dites and sternum orange. Palpus and legs orange- tions (cerrado and caatinga, Hueck 1972).
brown, darker ventrally. Abdomen orange, lighter
Micrathena plana (C.L. Koch)
than carapace, with one anteriorpairofspines over-
hanging carapace and 8 pairs of marginal black Acrosomaplanum C.L. Koch 1836:81, fig. 228.
thorns. Dorsum of abdomen flat with a slight pos- Micrathena plana: Levi 1985:509, figs. 311-325,
terior median longitudinal depression. Dorsal scler- map 6.
Toottiazledldeinsgktsha8n.6d,mcianruatpeacgera2n.u8lelsonags,i2n.5M.wicdley.peFaitras.t PlelocttyapneafdreogmeerSiurWianlacmkee,nlaoesrt)1N84E2W:17S4Y(NfOemNaYleMYho.-
femur 2.3; patella and tibia 2.5; metatarsus 1.0; tar- Acrosoma degeeri: Butler 1873:425.
sus 0.6. Second patella and tibia 2.3; third patella Micrathena degeeri: Petrunkevitch 1911: 368; Plat-
and tibia 1.4. Fourth femur 3.2; patella and tibia nick 2003.—
2.3; metatarsus 1.6; tarsus 0.7. Remarks. Micrathena degeeri was overlooked
334 THE JOURNAL OF ARACHNOLOGY
—
Figure 5. Geographic distribution of Micrathena clypeata (gray area, based on records from Levi
1985) and locality records for Micrathena cicuta new species (circles).
by Levi (1985), and the type specimens are lostlike As such, we here consider M. degeeri ajunior syn-
so many of the species described by Walckenaer onym ofM. plana.
(1842). According to the original description (Wal- We are especially grateful to Angela M.F. Pache-
ckenaer 1842:174), M. degeeri possesses an oval- co for the illustrations, and Cristina A. Rheims, Ri-
triangular abdomen with 12 spines: an anteriorpair cardo Pinto da Rocha, and Andre A. Nogueira for
of small ones (described as “mediocre” by the au- providing additional specimens for this study. We
thor), a pair of large and diverging posterior spines are also indebted to Fundagao CSN and IBAMA
with two small ones on the base, one dorsal and for allowing our studies in the ARIE Floresta da
one ventral. The sides of the abdomen were de- Cicuta. Antonio D. Brescovit, C.A. Rheims andtwo
scribed as bearing two small spines. This descrip- anonymous reviewers are acknowledged forhelpful
tion matches Levi’s (1985) illustrations ofMicrath- suggestions on the manuscript. This study was fi-
ena plana, a species distributed from Panama and nanced by FAPESP doctoral fellowship grants
the West Indies to Argentina, and the only species (Proc. 99/06089-4 to M.O. Gonzaga and 99/05659-8
with 12 abdominal spines recorded from Suriname. to A.J. Santos).
GONZAGA & SANTOS—NEW SPECIES OF MICRATHENA 335
LITERATURE CITED ais da Academia brasileira de Ciencias 17:261-
267.
Bonaldo, A.B, 1990. Descrigao do macho de Mi~ Petruekevitch, A. 1911. A synonymic index-cata-
crathena kirbyi (Perty, 1833) (Araneae, Aranei-
logue of spiders of North, Central and South
dae). Iheringia (ser. ZooL) 70:89-91.
Butler, A.G. 1873. A list ofthe spiders ofthe genus America with all adjacent islands, Greenland,
Bermuda, West Indies, Terra del Fuego, Gala-
Acrosoma. Proceedings ofZoological Society of
London 1873:420-429. pagos, etc. Bulletin of American Museum of
Natural History 29:1-791.
Koch, C.L. 1836. Die Arachniden. Nurnberg.
Hueck, K. 1972. As Florestas da America do Sul: Platnick, N.L 2003. The world spider catalog, ver-
ecologia, composigao e importancia ecoeomica. sion 3.5. American Museum of Natural History,
Poligono/Editora da Universidade de Brasilia, on line at <http://.research,amnh.org/entomology/
Sao Paulo. spiders/catalog 8l-87/index..html>
Levi, H.W. 1985. The spiny orb-weaver generaME Scharff, N. 1991. On the synonymy of Thaumas-
crathena and Chaetacis (Araneae: Araeeidae). tobellamoureiMello-Leitaoandlldibahaalbom-
Bulletin oftheMuseumofComparativeZoology aculata Keyselling (Araneae, Araneidae). Jour-
150:429-618. nal of Arachnology 19:155-156.
Lise, A.A. 1995. Description of the male of ME Walckenaer, C.A. 1842. Histoire naturelle des In-
crathenaperegrinatorum (Holmberg, 1883) (Ar- sectes, Apteres. Vol. 2. Librairie Encyclopedique
aneae, Araneidae). Revista Brasileira de Ento- de Roret, Paris.
mologia 39:221-223.
Mello-Leitao, C.E 1945. Tres novas especies de Manuscript received 27 May 2003, revised 2 Sep-
Gasteracanthinae e notas sobre a subfamflia. An- tember 2003.