Pecado, Hormiga & Scharff, 2005

Hormiga, Gustavo & Scharff, Nikolaj, 2005, Monophyly and phylogenetic placement of the spider genus Labulla Simon, 1884 (Araneae, Linyphiidae) and description of the new genus Pecado, Zoological Journal of the Linnean Society 143 (3), pp. 359-404 : 397-398

PECADO GEN. NOV.

Type species: Labulla impudica Denis, 1945

Etymology

Derived from the Spanish word ‘pecado’ (sin) in reference to widespread practice of erecting monotypic genera, especially in the Linyphiidae , in absence of a phylogenetic justification. The noun is masculine in gender.

Diagnosis

Males of Pecado can be distinguished from other linyphiid species by the presence of two cymbial processes ( Figs 14A, B , 15B – arrow; Denis, 1945; p. 13 and figs 26–28), one at the base of and the second in the dorsal median region of the cymbium, the bladelike projection of the proximal branch of the paracymbium ( Fig. 14A ) and the unusual coiling direction of the embolus. In Pecado impudicus the embolus coils anticlockwise (left palp, ventral view) for about one turn and then clockwise for almost its remaining length ( Fig. 14B ).

Description

Since the genus is monotypic, the description is given under Pecado impudicus .

Phylogenetics

See comments about its phylogenetic placement under the Discussion section.

Natural history

Unknown.

Composition

One species, Pecado impudicus ( Denis, 1945) .

Distribution

Algeria.

PECADO IMPUDICUS ( DENIS, 1945)

( FIGS 14 , 15 )

Labulla impudica Denis, 1945: 52 , figures 26–28

Type: Male holotype, label reads ‘ 1898.8.16. 34–50 (part) Labulla impudica J. Denis , Cape Verde, St. Vincent, Porto Grande. F. Cambridge’ (in BMNH, examined; the specimen is in poor condition and the right palp is missing). The type locality information, given on the label inside the vial with the holotype (handwritten by Denis), does not agree with the type locality data published by Denis (1945: 13): ‘ Algérie, Alger, 1 male (C. Hirst, 1911)’. Denis (1945: 1) states at the beginning of his paper on North African spiders that ‘during the course of a study of the spiders of the Canary Islands and the Cape Verde Islands ( Denis, 1941) I was able to examine part of a collection from the British Museum consisting of an assembly of specimens collected by a diversity of naturalists in very diverse regions of northern Africa’. Given the absence of additional specimens, it is impossible at this point to know with certainty the origin of the holotype of Labulla impudica . Nevertheless, it seems conceivable that during his study of the British Museum Canary and Cape Verde Islands specimens Denis mislabelled a specimen from Algeria, also from the British Museum, as coming from the Cape Verde. It seems logical to argue that if L. impudica had been collected in the Cape Verde Islands Denis would have published his description in his 1941 paper, where all other Cape Verde spiders were dealt with.

Diagnosis

See above, under genus description.

Description

Male (holotype): Most legs broken off, and cephalothorax and abdomen separated. Cephalothorax 1.98 long, 1.47 wide. Sternum 1.13 long, 0.93 wide. Abdomen 2.26 long, 1.04 wide. Cephalothorax and chelicerae brown, darker in cephalic area. Black rings around all eyes. Sternum brown. Legs same colour as cephalothorax, but with dark rings (annulations). Abdomen light grey, with dark grey pattern. Cheliceral stridulatory striae absent. AME diameter 0.14. Clypeus height 1.93 times one AME diameter. Chelicerae with four widely spaced prolateral teeth of variable size and two retrolateral teeth of variable size. Legs broken off, with several segments missing. It is therefore not possible to provide measurements of Femur I length and Tm I. Pedipalp as in Figures 14 , 15 . Pedipalpal tibia with two prolateral and two retrolateral trichobothria, a dorsal process (with numerous macrosetae) and an ectoventral process ( Fig. 14A ). Cymbium with two processes ( Figs 14A, C , 15B ), one at the base (with a pointed apex) and the second on the dorsomedian region (with a rounded apex, Fig. 15B – arrow). Paracymbium U-shaped, with a blade-like projection or crest running along dorsal region from the proximal branch through the median region ( Fig. 14A ). Paracymbium with ventral margin of proximal branch sclerotized and continuous with ectal cymbial margin but connected to cymbium by means of a membrane. Tegulum with a crest or sclerotized membrane on its apical region ( Fig. 14A ). Suprategulum with a blunt and very short distal apophysis hidden behind the terminal apophysis ( Fig. 15D, E ) and a pointed ectal apophysis ( Fig. 15E ). Radix a small enlargement of the embolus base ( Fig. 15D ). Terminal apophysis in mesal position, with a long and thin process ( Figs 14B , 15D ). Lamella characteristica with two long falciform processes, one anteriorly directed and the other posteriorly orientated but curving ectally in its distal portion ( Figs 14A, B , 15A ). Embolic membrane small, anteriorly directed, and located between the anterior process of the lamella and the terminal apophysis ( Fig. 15D ). Embolus filiform and extremely long ( Figs 14B , 15C ), coiling anticlockwise (left palp, ventral view) for about one turn and then clockwise almost its remaining length.

Female: Unknown.

Distribution

Only known from the type locality in Algeria (see comments under ‘Type’) .

Natural history

Unknown.

Material examined

Only the holotype.

Figures

Figure 14. Pecado impudicus (Denis), male palp (holotype). A, ectal; B, ventral; C, dorsoectal (arrows in A and C, posterior process of lamella, in B, distal tegular flap). Scale bars = 0.1 mm.

Figure 15. Pecado impudicus (Denis), male palp (holotype). A, meso ventral, schematic view of cleared palp with embolus rendered only in its basal region (down arrow, distal suprategular apophysis; right arrow, anterior process of lamella); B, posteromesal (arrows, cymbial processes); C, dorsomesal; D, embolic division and suprategulum, schematic view of cleared palp with embolus rendered only in its basal region (column and intersclerite membranes not rendered; right arrow, embolic membrane; up arrow, marginal suprategular apophysis); E, suprategulum (arrow, ectal suprategular apophysis). Scale bars = 0.1 mm.