Craspedisia cornuta (Keyserling, 1891),

Brescovit, Antonio D., Vasconcellos-Neto, João & Villanueva-Bonilla, German Antonio, 2020, Notes on the “ Pinocchio-cobweb-spider ” Craspedisia cornuta (Keyserling, 1891) from southeastern of Brazil (Theridiidae, Pholcommatinae), Zootaxa 4750 (2), pp. 211-224: 212-221

publication ID

https://doi.org/10.11646/zootaxa.4750.2.5

publication LSID

lsid:zoobank.org:pub:182B41E5-AAF4-4731-842E-6B090939221F

DOI

http://doi.org/10.5281/zenodo.3717812

persistent identifier

http://treatment.plazi.org/id/784EE247-0F51-FFD0-FF60-CADAFF56F807

treatment provided by

Plazi

scientific name

Craspedisia cornuta (Keyserling, 1891)
status

 

Craspedisia cornuta (Keyserling, 1891) 

Figures 1–7View FIGURE 1View FIGURE 2View FIGURE 3View FIGURE 4View FIGURE 5View FIGURE 6View FIGURE 7

Umfila cornuta Keyserling, 1891: 222  , pl. 8, fig. 163 (Male holotype from Nova Friburgo, Rio de Janeiro, Brazil, deposited in The Natural History Museum, London, not examined; Gö1di, 1892: 5: 233.

Craspedisia cornuta: Simon, 1894: 580  , fig. 587; Levi & Levi, 1962: 60, figs 275−280; Levi, 1963: 177, figs 27−31.

Note. The type has not been examined, but the figures presented by Keyserling (1891, fig. 163) and Levi (1963, figs 27–31) allow the species to be identified with certainty. We also emphasize that so far is the only species of the genus that occurs in Brazil.

Material examined. BRAZIL. São Paulo: Assis, Estação Ecológica de Assis (22°34’S, 50°24’W), 1M, 25–30.XI.2002, Equipe Biota coll. ( MCN 41264View Materials)GoogleMaps  ; Jundiaí, Reserva Biológica da Serra do Japi (23°13’53.1”S 46°56’08.6”W), 1F, V /2016 – I/2017 ( IBSP 215575View Materials)GoogleMaps  ; 1F, V /2016 – I/2017 ( IBSP 215576View Materials)  ; 1M 1F, V /2016 – I/2017 ( IBSP 215577View Materials)  ; 1F, V /2016 – I/2017 ( IBSP 215578View Materials)  ; 1F, V /2016 – I/2017 ( IBSP 215579View Materials)  ; 2F, V /2016 – I/2017 ( IBSP 215580View Materials)  ; 1F, V /2016 – I/2017 ( IBSP 215581View Materials)  ; 1F, V /2016 – I/2017 ( IBSP 215582View Materials)  ; 1M, V /2016 – I/2017 ( IBSP 215583View Materials)  ; 1M, V /2016 – I/2017 ( IBSP 215584View Materials)  ; 1F, V /2016 – I/2017 ( IBSP 215585View Materials)  ; 2F, XI/2016 ( IBSP 215586View Materials)  ; 1F, XI/2016 ( IBSP 215587View Materials)  ; 1M, XI/2016 ( IBSP 215588View Materials)  ; 1F, XI/2016 ( IBSP 215590View Materials)  ; 1M, XI/2016 ( IBSP 215591View Materials)  ; 1M 1F, XI/2016 ( IBSP 215592View Materials)  ; 1F, XI/2016 ( IBSP 215596View Materials)  ; 1F, XI/2016 ( IBSP 215597View Materials)  , all collected by G. Villanueva; São Paulo (23°33’01”S– 46°38’02”W),1M, 1986, no coll. ( IBSP 27388View Materials); (Campus USP)GoogleMaps  , 1M, 27/XI/2001, F.S. Cunha coll. ( IBSP 32134View Materials); (Campus Instituto Butantan)  , 1M, 02/XII/2010, A.D. Brescovit coll. ( IBSP 210147View Materials)  ; Paraná: Tijucas do Sul (25º55’41”S– 49º11’56”W), Lagoa, Morro do Cabral , 1M, VII/2000, J. Ricetti coll. ( IBSP 39029View Materials)GoogleMaps  ; Guarapuava, Estância Santa Clara (25°40’S– 52°01’W), 1M 1F, 22.XI.1987, A. D. Brescovit coll. ( MCN 17125View Materials)GoogleMaps  ; Jundiaí do Sul, Fazenda Monte Verde (23°26’S– 50°16’W), 1M 1F, 23.XI.1987, A.D. Brescovit coll. ( MCN 17184View Materials)GoogleMaps  ; Rio Grande do Sul: Derrubadas, Parque Estadual do Turvo (27°8′44″S– 53°53′10″W), 27–31.X.2003, 1M 1F, R. Ott et al. coll. ( MCN 37781View Materials)GoogleMaps  ; Santa Maria (29°41’02”S– 53°48’25”W), Campus Universidade Federal de Santa Maria , 1M 1F, 12. VI.2000, L. Indrusiak coll. ( MCN 37876View Materials)GoogleMaps  ; Triunfo (29°56’34”S– 51°43’04”W), Parque Copesul de Proteção Ambiental , 1M 1F, 12.I.1989, A.B. Bonaldo coll. ( MCN 18084View Materials)GoogleMaps  ;

Diagnosis. Craspedisia cornuta  resemble C. spatulata  from Dominican Republic, but can be distinguished by embolus rectangular and shorter and smallest conductor while in C. spatulata  the embolar base is rounded; embolus longer and largest conductor (see Levi, 1963, fig. 33; Fig. 4View FIGURE 4 C−H). If compared with the Chinese Craspedisia longioembolia  , the proboscis in this species is very short and the distal area of embolus long and filiform (see Yin et al., 2003, figs 2−3, 5). The females of both other species, C. spatulata  and C. longioembolia  are unknown.

Description. Male (IBSP 215592). Coloration of specimen still dead in alcohol: dorsally orange carapace with distal cephalic black area ( Fig. 1View FIGURE 1 A−B), ventrally with endites, labium and sternum greyish. Legs with yellowish coxae, trochanters and base of femurs, remaining dark gray ( Fig. 1DView FIGURE 1). Abdomen gray with four rounded dorsal black spots and ventrally gray ( Fig.1AView FIGURE 1). Carapace oval, covered with long hairs on prosomal pits and excavated base, thoracic groove deep and transversal, in the posterior third, posteriorly with large and stridulatory plate subrectangular, covering the pedicel, with more than 50 longitudinal grooves on the plate. Eyes in a projected cephalic area ( Fig. 1BView FIGURE 1), with median anterior eyes slightly larger than the others ( Figs 2View FIGURE 2 A−B, G−H). Proboscis thick, fingerlike, curved down, covered with long bristles throughout, inserted in the median region of the clypeus, below the AME, of which it is separated by a diameter ( Figs. 2View FIGURE 2 B−F). Clypeus projected on the chelicerae, with differentiated border and split in the median region ( Fig. 2D, FView FIGURE 2). Chelicerae with three teeth on anterior margin (one teeth in Levi, 1963) ( Fig. 3AView FIGURE 3). Endites truncated, with serrula presenting almost 30 small teeth in a row. Labium rounded, fused to sternum. Sternum tuberculate, covered with long hairs ( Fig. 3BView FIGURE 3). Slender legs, with three claws, anterior with six ventral teeth, median elongated, smooth and curved, and false claws represented by 3−5 hairs ( Fig. 3CView FIGURE 3); trichoboth- ria with rounded base, circular aperture and long hair ( Fig. 3DView FIGURE 3), distributed in two rows on the dorsal area of legs I–IV; tarsal organ rounded, smooth with circular aperture ( Fig. 3View FIGURE 3 G−H) and chemosensitive setae as in female. Abdo- men with large ventral plate, which ends before the spinnerets, furrowed in the posterior third, where it houses two furrowed areas, where are the epiandric fusules ( Figs 3EView FIGURE 3, legs; 3F, cymbium). Colulus small and triangular ( Fig. 3FView FIGURE 3). Male palp: short tibiae, enlarged distally with elongate setae, and a dorsal basal, rounded trichobothria ( Figs. 4View FIGURE 4 A−B). Cymbium oval, with Theridiid cymbial hook elongated ( Fig. 4E, HView FIGURE 4). Subtegulum canoe-shaped, supporting the tegulum and distal structures ( Figs 4C, EView FIGURE 4) and presenting a globose retrolateral projection ( Fig. 4HView FIGURE 4). Tegulum large, projected posteriorly and conic at tip, with tegular apophysis conical, behind the embolus ( Fig. 4View FIGURE 4 E−F); median apophysis originating behind the embolus, distally flattened; pedunculate conductor, with distal area flattened, supporting the tip of embolus; embolus thick, longitudinally sulcated, with large and subquadrate base, having convex striations in the median area, ( Figs 4View FIGURE 4 C−H).

Female. Coloration (from IBSP 215592) as in male, except distal area of tibia and metatarsus I–II darker and abdomen black, with small black spots; and epigynal plate orange as the anterior and lateral plates ( Fig. 1View FIGURE 1 D−F).. Carapace covered with less long hairs on prosomal pits and concentered in the cephalic area, stridulatory plate subrectangular, with less longitudinal grooves on the plate that the male ( Figs 5View FIGURE 5 A−C). Clypeus and eyes ( Fig. 5CView FIGURE 5) as in male, proboscis absent ( Fig. 1DView FIGURE 1). Chelicerae short, with two teeth on anterior margin ( Fig. 5DView FIGURE 5). Endites, serrula and sternum as in male ( Figs 5View FIGURE 5 E−G). Labium largest the male, fused to sternum ( Fig. 5EView FIGURE 5). Legs as in males, with three claws, anterior hairs and false claws of the legs I–II not impregnated with possible sap of plant material ( Fig. 6FView FIGURE 6) and posteriors legs III–IV with hairs and false claws covered by this material ( Fig. 6View FIGURE 6 D−E). Trichobothria with rounded base, circular aperture and long hair ( Fig. 6AView FIGURE 6), distributed in the leg as in male ( Fig. 6View FIGURE 6 A−B); tarsal organ capsuled, smooth with circular aperture ( Fig. 5HView FIGURE 5) and chemosensitive setae smooth and elongated ( Fig. 6CView FIGURE 6). Abdomen with ventral plate lesser than male, circular anteriorly and having laterally with a group of hard spines, probably to rub in the stridulatory plate ( Fig 7View FIGURE 7 A−C). Colulus oval and elongated at tip ( Fig. 7DView FIGURE 7). Epigynum with ventral plate larger than long, subrectangular ( Fig. 7EView FIGURE 7) or semicircular ( Fig. 7FView FIGURE 7), with ample anterior opening. Internally with globose spermathecae, short copulatory ducts united at base, elongated fertilizations ducts and large inner area of the atrium ( Fig. 8View FIGURE 8 A−B; see Levi, 1963, fig. 28).

Natural History. Craspedisia cornuta  individuals are found in tree trunks of Piptadenhia gonoacantha (Mart.) JF Macbr. ( Fabaceae  ), Croton floribundus Spreng.  ( Euphorbiaceae  ), and Zanthoxylum rhoifolium Lam.  ( Rutaceae  ) in ranges ranging from 0.5m– 1.7 m height (n = 55) in forest areas. Its distribution in the trunks is not random, occurring more frequently in places where there are shelter structures such as loose bark or protuberances and moss coverings along the trunk, which act as a rain protection roof ( Fig. 9A, FView FIGURE 9). The webs are star shaped with anterior aperture ( Fig. 9View FIGURE 9 B−D). The web is slightly inclined from the base towards the shelter ( Fig. 2AView FIGURE 2). Craspedisia cornuta  has nocturnal habits, remaining in this period in the trunk, outside the web. During the day, they are sheltered in the back part of the web ( Fig. 9EView FIGURE 9). The webs are usually found in lichen and moss-lined trunks ( Fig. 9View FIGURE 9). Adult individuals were found mainly in the summer, in the months of December and January ( Fig. 10View FIGURE 10), a period of higher rainfall where lichens and mosses are lush. According to Paquin & Dupérré (2001), the reproductive period of a spider species population is determined by the peak abundance of adult males. Thus we understand that the population of C. cornuta  presents a spring and summer stenochronic phenological pattern with a very marked period of activity of adult spiders in a defined period of the year—according to the classifications of Tretzel (1954) and Paquin & Dupérré (2001). This phenological pattern where sexually active males are available for a few months has also been recorded in other spider populations in the temperate ( Merrett 1967) and Neotropical regions ( Villanueva-Bonilla & Vasconcellos-Neto 2016; Villanueva-Bonilla et al. 2018). In the case of autumn 2016, some remaining adult females from the previous summer were still found ( Fig. 10View FIGURE 10), probably individuals who had less pressure for predators or fluctuating climatic conditions in the region.

One aspect that caught our eye when examining SEM images of the nails of the legs was the presence of a hardened substance covering the false claws and distal bristles to the legs. These characteristics were observed only in the legs III−IV of the females ( Fig. 5View FIGURE 5 D−E), being absent in the legs I−II ( Fig. 5FView FIGURE 5), as well as in the legs of the males where we did not observe these inlays ( Fig. 2CView FIGURE 2). We suspect that the substance could be sap of lichens or mosses, where females usually build their refuges and remain largely hidden.

Distribution. Known from the Rio de Janeiro, São Paulo, Paraná and Rio Grande do Sul states in Brazil ( Fig. 11View FIGURE 11).

MCN

McNeese State University

V

Royal British Columbia Museum - Herbarium

USP

University of the South Pacific

R

Departamento de Geologia, Universidad de Chile

VI

Mykotektet, National Veterinary Institute

Kingdom

Animalia

Phylum

Arthropoda

Class

Arachnida

Order

Araneae

Family

Theridiidae

Genus

Craspedisia

Loc

Craspedisia cornuta (Keyserling, 1891)

Brescovit, Antonio D., Vasconcellos-Neto, João & Villanueva-Bonilla, German Antonio 2020
2020
Loc

Craspedisia cornuta

Levi, H. W. 1963: 177