Graycassis, PLATNICK, 2000

PLATNICK, NORMAN I., 2000, A Relimitation And Revision Of The Australasian Ground Spider Family Lamponidae (Araneae: Gnaphosoidea), Bulletin of the American Museum of Natural History 2000 (245), pp. 1-328 : 225-227

publication ID

https://doi.org/ 10.1206/0003-0090(2000)245<0001:ARAROT>2.0.CO;2

persistent identifier

https://treatment.plazi.org/id/03B887CE-B4BB-FF25-C59E-71DAE103F97D

treatment provided by

Felipe

scientific name

Graycassis
status

gen. nov.

Graycassis View in CoL , new genus

TYPE SPECIES: Graycassis marengo , new species.

ETYMOLOGY: The generic name is in honor of the two collectors who are responsible for obtaining most of the known specimens, Drs. M. Gray and G. Cassis of the Australian Museum, and is considered masculine in gender.

DIAGNOSIS: Males are easy to recognize because of their greatly elaborated median apophysis (as in figs. 542, 574) and lobate retrolateral tibial apophyses (as in figs. 543, 575). Females have varied epigyna, but the posterior ducts are typically y­shaped, with each duct having a straight base leading to an oblique continuation (as in figs. 545, 577).

DESCRIPTION: Medium size spiders, total length of males 3.4–8.8, of females 4.8–9.9. Carapace reddish brown, surface with scattered low tubercles, pars cephalica with long, dark, thin setae; thoracic groove very long, longitudinal, shallow. Eight subequal eyes in two rows, anterior medians circular, dark, laterals oval, light, posterior medians irregularly oval, flattened, light; from above, both eye rows nearly straight, from front, anterior row nearly straight, posterior row strongly procurved; anterior medians separated by their diameter, slightly closer to anterior laterals; posterior medians separated by more than their diameter, farther from posterior laterals; anterior and posterior laterals separated by more than their diameter; median ocular quadrangle wider in back than in front and than long. Chelicerae, sternum, and mouthparts reddish brown; chilum wide, triangular, accompanied by second, longitudinal posterior chilum (extremely narrow sclerite separating bases of chelicerae posteriorly); chelicerae with distinct lateral boss, anterior sur­ face with depressed, relatively unsclerotized oval area near promargin; promargin with row of long setae originating in line along base of fang, seta closest to fang bent near base, extending behind other promarginal setae to near midline; promargin with three teeth, median one largest, proximal one smallest; retromargin with two large, widely separated teeth. Labium elongate, rectangular, only gradually narrowed anteriorly, posterior margin truncate, anterior margin distinctly invaginated at middle, surface not depressed medially. Endites obliquely depressed, with deep groove along margin near labium not sharply demarcated, groove wider anteriorly than posteriorly; serrula long, with single row of teeth; anterior surface with distinct sieve plate of maxillary gland openings set in oval of unsclerotized cuticle. Sternum slightly elevated, with gently sloping lateral margins, not expanded anteriorly, with triangular extensions to and between coxae; surface with few low tubercles. One epimeric sclerite on each side, above each coxa, not reaching sternal triangles, not fused to carapace or pedicel. Pedicel consisting of large, diamond­shaped sclerite bearing narrow anterior margin meeting posterior tip of sternum at slightly procurved line.

Anterior edge of abdomen of male with complete sclerotic ring formed by strong epigastric scutum plus strong dorsal abdominal scutum covering about one­half of length of dorsum, females with dorsal scutum represented only by small rectangular plate above pedicel, restricted to lower half of anterior surface of abdomen; cuticle with long, recumbent setae; epigastric scutum accompanied posterolaterally by pair of oval, deeply invaginated sclerites bearing clearly elevated anterior rim; sclerites separated by membranous lobe, anterior rim of sclerites fitting un­ der epigastric scutum; colulus represented by setae on slightly sclerotized cuticle; posterior spiracle procurved, inconspicuous. Anterior lateral spinnerets tubular, separated at base by about their diameter, with about three piriform gland spigots, cuticle representing distal, second spinneret segment restricted to semicircle surrounding major ampullate gland spigots (piriform gland spigots surrounded only by soft cuticle); posterior median spinnerets of males large, tubular, of fe­ males with anteriorly expanded tips, bases occupied by three enormously widened cylindrical gland spigots; posterior lateral spinnerets two­segmented, those of females with two greatly widened cylindrical gland spigots.

Leg spination reduced; typical leg spination pattern (only surfaces with spines list­ ed): femora I–IV d1­0­0; tibiae: III p0­1­1, v1p­2­2, r0­1­1; IV p0­0­1, v2­2­2, r1­0­1; metatarsi: III p0­1­0, v2­1p­0, r0­1­0; IV p0­ 1­1, v2­2­0, r0­1­0. Most leg surfaces with long setae; coxae with very slight tubercles; anterior coxae with slightly protuberant posterolateral corners, widened at about half their length; trochanters with shallow but distinct notch; anterior tarsi with weak, divided scopulae, composed of laterally directed setae; posterior metatarsi with weak distal preening brushes; posterior tarsi with very weak scopulae; tarsi with two dentate claws, claw tufts reduced to few long setae, restrict­ ed to ventral portion of claw tip; trichobothria present on distal leg segments, in two rows. Female palpal tibia and tarsus with long, thin spines; female palpal tarsus with long, basally dentate claw.

Male palp with lobe­shaped, often bipartite retrolateral tibial apophysis; cymbial surface excavated opposite tibial apophysis; tegulum bulbous, with slight median projection; embolus relatively short, originating at middle of prolateral side of bulb, accompanied by membranous conductor; median apophysis enormously elaborated, often with spurs; embolar base with at most a slight translucent flange, without distinct apophysis. Epigynum with anterior ridge; spermathecae heavily sclerotized, often with accessory lobes.

KEY TO SPECIES OF GRAYCASSIS

1. Males............................. 2

– Females (those of G. enfield and G. scrub View in CoL unknown)......................... 11

2. Median apophysis distally bifid, with long prolateral prong directed distally (figs. 542, 546, 550)........................ 3

– Median apophysis otherwise........... 5

3. Embolus long, narrow, unmodified (fig. 550)........................... dorrigo

– Embolus short, wide, twisted (figs. 542, 546) ................................ 4

4. Median apophysis relatively wide (fig. 542).......................... marengo View in CoL

– Median apophysis relatively narrow (fig. 546).............................. styx View in CoL

5. Median apophysis with elongated, prolaterally directed tip (figs. 570, 574, 578).. 6

– Median apophysis with short tip (figs. 554, 558, 562, 566).................... 8

6. Median apophysis distally convex (fig. 578)............................ scrub View in CoL

– Median apophysis distally concave (figs. 570, 574)............................ 7

7. Tip of median apophysis relatively narrow (fig. 570)..................... boss View in CoL

– Tip of median apophysis relatively wide (fig. 574)........................ bulga View in CoL

8. Tip of median apophysis twisted, sinuous (figs. 558, 562)................... 9

– Tip of median apophysis not twisted (figs. 554, 566)....................... 10

9. Tip of median apophysis relatively long (fig. 558)..................... chichester View in CoL

– Tip of median apophysis relatively short (fig. 562).................... barrington View in CoL

10. Median apophysis relatively short (fig. 566)............................ enfield

– Median apophysis relatively long (fig. 554)........................... bruxner View in CoL

11. Epigynum with distinct anteromedian septum (figs. 544, 548, 552, 564, 572, 576).. 13

– Epigynum without anteromedian septum (figs. 556, 560).................. 12

12. Epigynal ducts relatively short (figs. 556, 557)....................... bruxner View in CoL

– Epigynal ducts relatively long (figs. 560, 561)......................... chichester View in CoL

13. Epigynal septum relatively wide, separating anterior epigynal margins (figs. 572, 576) ............................... 14

– Epigynal septum narrow, not separating anterior epigynal margins (figs. 544, 548, 552, 564)....................... 15

14. Epigynum relatively narrow (fig. 572).................................. boss View in CoL

– Epigynum relatively wide (fig. 576)... bulga View in CoL

15. Epigynal septum relatively long (fig. 564).......................... barrington View in CoL

– Epigynal septum relatively short (figs. 544, 548, 552)....................... 16

16. Anterior portion of epigynum relatively long (fig. 544).................. marengo View in CoL

– Anterior portion of epigynum shorter (figs. 548, 552)....................... 17

17. Median epigynal ducts oblique (figs. 548, 549).......................... styx View in CoL

– Median epigynal ducts recurved (figs. 552, 553)....................... dorrigo

Kingdom

Animalia

Phylum

Arthropoda

Class

Arachnida

Order

Araneae

Family

Lamponidae

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