Megalostrata paludosa, Bonaldo & Galán-Sanchez & García, 2024

Bonaldo, Alexandre B., Galán-Sanchez, M. Antonio & García, Fabián, 2024, Advances on the taxonomy of Megalostrata Karsch, 1880 (Araneae, Corinnidae, Corinninae), with descriptions of two new species, Zootaxa 5458 (4), pp. 495-523 : 513-521

Megalostrata paludosa spec. nov.

Figs 15–25

Type material. Holotype ♂: COLOMBIA: Bolivar: Cartagena de Indias, Isla Tierra Bomba, Corregimiento Caño del Oro (10°20’46.3”N 75°32’28.0”W, 0 m a.s.l.), leg. MangrArachTeam, 26–30.VII.2018 ( MUSEUV 2791 ).

Paratypes: same data ( MUSEUV 2792 , 1 ♀; 2794, 2♀; 2795, 2♀); Corregimiento Bocachica (10°19’19.6”N 75°35’13.9”W, 0 m a.s.l.) ( MPEG 39054 , 1♂, 1♀; 39055, 2♂, 1♀; 39056, 1♂ SEM; MUSEUV 2793 , 1♀; ICN 103414, 1♂; 103415, 1♀) ; Isla La Boquilla, Corregimiento la Boquilla [10°28’13.9”N 75°29’39.1”W, 0 m a.s.l.] (1♂ IAvH-I-7667, 1♀ IAvH-I-7668; MUSEUV 2796 , 1♂, 1♀) .

Etymology. The specific name is a Latin adjective meaning marshy, referring to the fact that all specimens known so far were collected in mangrove swamps.

Diagnosis. Males of M. paludosa spec. nov. resemble those of M. raptor by the entire RTA, differing by the presence of an apical field of teeth on the apical tegular process (tegular process rounded, smooth in M. raptor , Fig. 3A ) and by the retro-apically oriented embolus (oriented retro-basally in M. raptor, Bonaldo 2000 , fig. 304). They share with M. depicta the retro-apically oriented embolus but differ by the apical tegular process with a field of apical teeth (rounded, smooth in M. depicta , Fig. 3C ) and by the entire RTA (bifid in M. depicta , Fig. 3D ) ( Figs 22A, B , 23A, B ). Females are similar to those of M. monistica and M. bruneri by the short, bulbous secondary spermathecae ( Figs 12A, B , 14C ). They differ from those of M. monistica by the posterior margin of the epigynal plate slightly recurved, without a median invagination (posterior margin of epigynal plate strongly invaginated in M. monistica , Fig. 12A ) and from those of M. bruneri by the large primary spermathecae, larger than the posterior atrium height in diameter, positioned at the level of the posterior atrium (small primary spermathecae, with diameter almost equal to the posterior atrium height, positioned anteriorly to posterior atrium in M. bruneri , Fig. 14C ) ( Figs 22C, E , 23C, D , 24A, B ).

Description. Male (holotype). Carapace brown, with two paramedian reddish-brown stripes, cephalic region darker. Chelicerae, labium, and endites reddish-brown. Sternum yellow, with darker margins. Legs reddish-brown. Abdomen dorsum yellowish-white, with two lateral dark strips merging posteriorly and six pairs of black spots ( Fig. 15A, C ). Total length 9.19. Carapace 3.982 long, 3.502 wide, finely granulated ( Figs 16A, B ). Clypeus height 0.243. Eye diameters: AME 0.179, ALE 0.172, PME 0.172, PLE 0.129. Interocular distances: AME-AME 0.159, AME-ALE 0.109, PME-PME 0.337, PME-PLE 0.274, ALE-PLE 0.106. Chelicerae: 2.867 length; retromargin with two large, subequal teeth, apical one conical, basal one laminar; promargin with three small, subequal teeth, distal one set apart; fang long, strong, scythe-shaped, with curved median bulge, fang base tubular, fang apex conical ( Figs 17B– D ). Endites strongly excavated prolaterally ( Fig. 17A ). Sternum 2.004 long, 2.091 wide; strongly rebordered, with round setae bases ( Figs 16C, D ). Leg measurements: I—4.692, 1.507, 4.945, 4.039, 1.634, 16.817; II—4.344, 1.485, 3.949, 3.845, 1.549, 15.172; III—4.013, 1.632, 3.843, 3.847, 1.427, 14.762; IV—4.537, 1.456, 4.367, 4.612, 1.624, 16.596. Leg spination: I—femur d1-1-1, p0-0-1; tibia p2-2-2-2; metatarsus p2-2. II—femur d2-2-1, p0-1-1; tibia v2- 2-2-2, p1-0-1; metatarsus v2-2-0, p1-1-0. III—femur d1-1-1, p1-1-1, r1-1-1; tibia v1-1-1, p1-1, r1-1; metatarsus v2- 2-2, p1-1-1. IV—femur d1-1-2, v2-2-2, p0-1-1, r0-1-1; tibia p1-1-1, v2-2-0, d1-0-0; metatarsus p1-1-1, v2-2-2, d1- 1-1. Legs densely covered by feathery scales ( Fig. 19 ); metatarsi with two ventrolateral rows of scopular setae; long macrosetae, sockets with long extensions ( Figs 19A, C ); claws with dense tufts of tenant setae ( Fig. 19D ). Abdomen 5.209 long, 2.289 wide. Male palp. Tibia nearly half of cymbium length. RTA unique, laminar, sub-quadrangular, apex rounded, prolateral surface concave. Cymbial retrolateral basal process moderately pronounced, represented by a concavity; cymbial basal prolateral process absent; subtegulum widely exposed prolaterally; spermophore with five ventral folds; tegular process truncated, with field of small, irregular teeth-like projections at apex; embolus comma-shaped, broad, laminar at base, apex conical, sinuous ( Figs 20 , 22A, B ).

Female (MPEG 39055). Carapace yellow, with reddish-brown paramedian stripes, cephalic region darker. Chelicerae brown, labium and endites reddish-brown. Sternum reddish-brown, with yellow margins. Legs yellow, metatarsus and tarsus yellowish-brown. Abdomen dorsum yellowish-white, with five pairs of black spots, first one larger. Posteriorly with narrow, uninterrupted dark band dark and large black spot near spinnerets. Colulus represented by sub-triangular plate with few simple hairs ( Fig. 18A ). Spinnerets: ALS ( Fig. 18B ) with nearly 46 piriform spigots and two major ampullate spigots; PMS ( Fig. 18D ) with six aciniform spigots, one tartipore, two minor ampullate spigots and three cylindrical spigots ( Fig. 18C ); PLS with nearly 28 piriform spigots and two cylindrical spigots ( Fig. 18D ). Total length 7.787. Carapace 3.707 long, 3.377 wide. Clypeus height 0.205. Eye diameters: AME 0.235, ALE 0.133, PME 0.147, PLE 0.163. Interocular distances: AME-AME 0.156, AME-ALE 0.099, PME-PME 0.280, PME-PLE 0.160, ALE-PLE 0.066. Chelicerae with two large retrolateral triangular, subequal teeth, prolateral with three, median larger. Sternum 2.008 long, 1.656 wide. Leg measurements: I—4.276, 1.801, 4.339, 2.997, 1.477, 14.890; II—4.159, 1.849, 3.947, 2.565, 1.328, 13.848; III—3.838, 1.045, 3.043, 3.577, 1.362, 12.865; IV—4.315, 1.364, 4.119, 3.275, 1.173, 14.246. Leg spination: I—femur d1-2-2, p0-1-0; tibia p1-1, r1-1; metatarsus v1-1-1-1-1. II—femur d1-2-2; tibia p1-1, r1-1; metatarsus v1-1-1-1-1. III—femur d1-1-1, p0-1-1; tibia p1-1; metatarsus d2-2-2, v1-1-1, p1-1-1, r1-1-1. IV—femur v0, d2-1-1-1, r1-1; tibia p1-1, r1-1; metatarsus d2-2-0, r1-1. Abdomen 4.803 long, 2.671 wide. Epigynum: Epigynal plate subtriangular, anterior portion convex, posterior atrium defined by sub-quadrangular median area posterior to copulatory openings; transversal anterior ridge absent; posterior margin of epigynal plate without median invagination; margin of posterior plate excavation slightly procurved in posterior view; copulatory openings exposed in epigynal plate surface, placed on deep pits above the atrium. Copulatory ducts short, represented by wider than long tube; secondary spermathecae short, bulbous; primary spermathecae globular, large (diameter larger than atrium height); fertilization ducts directed anteriorly ( Figs 21 , 22C–E , 23C, D , 24 ).

Variation. (4♂)Total 8.900 –9.300.Carapace 3.780 –3.990 long, 3.466 –3.700.Leg I—4.256–4.300, 1.800–1.900, 4.299–4.500, 2.980–3.005, 1.477–1.530. (4♀) Total 7.260 –8.220. Carapace 3.335 –4.000 long, 3.150 –4.020 wide. Leg I— 4.100–4.470, 1.760–1.902, 4.330–4.400, 2.900–3.150, 1.360–1.500. The prolateral surface of the femur III of males may bear an additional median spine (19B). The female epigynum varies in degree of sclerotization of the posterior atrium and of the copulatory opening pits ( Fig. 24B ).

Distribution. Only known from the islands of Tierra Bomba and La Boquilla, Cartagena, Colombia ( Fig. 25 ).

Figures

FIGURE 3. A, B Megalostrata raptor (L. Koch, 1866), male (UNAM INVPICV071):A palp, ventral view. B palp, retrolateral view; C, D Megalostrata depicta (O. Pickard-Cambridge, 1895), male (UNAM CORINN0039): C palp, ventral view. D palp, retrolateral view. Abbreviations: E, embolus; RTA, retrolateral tibial apophysis; TP, tegular process. Scale bar: 2 mm.

FIGURE 12. Megalostrata monistica (Chamberlin, 1924): female, Nayarit, Mexico (CAS 9119037):A epigynum, ventral view; B same, dorsal view; C same, posterior view. Scale bars: 0.2 mm.

FIGURE 14. Megalostrata bruneri (Bryant, 1936), female holotype (MCZ): A dorso-lateral view; B abdomen, ventral view; C epigynum, ventral view. Scale bars: A 5 mm, B 1 mm, C 0.5 mm.

FIGURE 15. Megalostrata paludosa spec. nov., male holotype (A, C) and female paratype (B, MUSEUV 2792):A male, dorsal view; B female, ventral view; C male, lateral view. Scale bars: 1 mm.

FIGURE 16. Megalostrata paludosa spec. nov., male paratype (MPEG 39056): A carapace, dorsal view; B eyes, dorsal view; C sternum, ventral view; D sternum cuticle, ventral view. Scale bars: A, C 1000 μm; B 500 μm; D 200 μm.

FIGURE 17. Megalostrata paludosa spec. nov., male (MPEG 39056): A mouthparts; B right chelicerae, ventral view; C left chelicerae, retrolateral view; D same, teeth. Abbreviations: FF fang furrow; QPT cheliceral promarginal teeth. Scale bars. A, D 500 μm; B, C 1000 μm.

FIGURE 18. Megalostrata paludosa spec. nov. (MPEG 39056), female: A spinnerets, posterior view; B right anterior lateral spinneret; C right posterior median spinneret; D left posterior lateral spinneret.Abbreviations:Ac, aciniform gland spigot; ALS, anterior lateral spinnerets; AT, anal tubercle; Co, colulus; Cy, cylindrical gland spigot; MaAmp, major ampullate gland spigot; MiAm, minor ampullate gland spigot; PLS, posterior lateral spinnerets; PMS, posterior median spinnerets; Pi, piriform gland spigot; Tp, tartipore; TrSP, tracheal spiracle. Scale bars. A 500 μm; B–D 50 μm.

FIGURE 19. Megalostrata paludosa spec. nov. (MPEG 39056), male legs: A left metatarsus III, ventro-lateral; B left femur III, prolateral; C, left metatarsus III, macrosetal socket, ventral; D left tarsus IV, claw tuft details, lateral. Scale bars: A, B 500 μm; C 50 μm; D, 100 μm.

FIGURE 20. Megalostrata paludosa spec. nov., male (MPEG 39056), right palp: A ventral view; B retro-ventral view; C embolus,ventral; D tegular process, ventral.Abbreviations:CRP, cymbial retrolateral basal process; E, embolus; RTA,retrolateral tibial apophysis; T, tegulum; TP, tegular process; St, subtegulum. Scale bars. A, B 500 μm; C 100 μm; D 50 μm.

FIGURE 21. Megalostrata paludosa spec. nov., female genitalia, digested (MPEG 39055): A ventral view; B same, details of copulatory opening; C dorsal view; D same, details.Abbreviations: CO, copulatory opening; FD, fertilization ducts; S1, primary spermathecae; S2, secondary spermathecae. Scale bars. A, C, D 200 μm; B 50 μm.

FIGURE 22. Megalostrata paludosa spec. nov.. A, B male holotype:A palp, ventral view; B palp, retrolateral view. C–E female paratype (MUSEUV 2796): C epigynum, ventral view; D same, posterior view; E same, dorsal view. Scale bars. 0.2 mm.

FIGURE 23. Megalostrata paludosa spec. nov.. A, B male holotype: A palp, ventral view; B palp, retrolateral view. C, D female paratype (MUSEUV 2796): C epigynum, ventral view; D same, dorsal view. Abbreviations: CO, copulatory opening; CRP, cymbial retrolateral basal process; E, embolus; FD, fertilization ducts; RTA, retrolateral tibial apophysis; S1, primary spermathecae; S2, secondary spermathecae; TP, tegular process. Scale bars. A, B 0.5 mm, C, D 0.2 mm

FIGURE 24. Megalostrata paludosa spec. nov., A, C, D female paratype (MUSEUV 2796), B female paratype (MPEG 39054): A undigested epigynum, ventral view; B same, ventral view, variation; C same, posterior view; D same, digested, posterior view. Abbreviations: CO, copulatory opening; EPC, epigastric plate cuticle. Scale bars. 0.2 mm.

FIGURE 25. Known geographical distribution of Megalostrata species.