Modisimus enriquillo, 2010

Huber, Bernhard A., Fischer, Nadine & Astrin, Jonas J., 2010, High level of endemism in Haiti’s last remaining forests: a revision of Modisimus (Araneae: Pholcidae) on Hispaniola, using morphology and molecules, Zoological Journal of the Linnean Society 158 (2), pp. 244-299 : 276-277

MODISIMUS ENRIQUILLO HUBER & FISCHER SP. NOV.

( Figs 49, 50 , 72 , 154–156 , 199 )

Type: Male holotype from north-west of Paraiso, at ~ 18°02.4 ′ N, 71°11.6 ′ W, Barahona Prov., Dominican Republic ; secondary forest at 180 m a.s.l., domeshaped webs under dead palm fronds on ground, 7 December 2007 (B.A. Huber), in ZFMK ( Haiti 58b) .

Etymology: The species name refers to Enriquillo, the Taino chief of the 1519 rebellion against Spanish subjugation; it is used as a noun in apposition.

Diagnosis: Medium-sized species with pair of small apophyses posteriorly on female sternum ( Figs 49, 50 ), distinctive epigynum shape ( Figs 49, 50 ), otherwise very similar to M. tiburon sp. nov. (palps, male chelicerae).

Male (holotype): Total length, 2.9; carapace width, 1.3. Leg 1: 28.6 (7.6 + 0.5 + 7.4 + 10.9 + 2.2); tibia 2, 4.9; tibia 3, 3.9; tibia 4, 5.2. Tibia 1 L/d: 58. Habitus similar to M. seguin sp. nov. (cf. Figs 27–29 ), carapace pale ochre-white, with wide brown lateral margins above legs 2–4, thoracic furrow also dark brown, ocular area and clypeus brown, clypeus with pair of lateral dark-brown bands; sternum medially brown with some light spots, laterally whitish; legs light ochre-brown, tips of femora and tibiae whitish, distinct darker rings subdistally on femora and tibiae; abdomen bluish grey, densely covered with black spots dorsally (except heart area) and laterally, with distinct white lines made of small spots; genital area and area in front of spinnerets light brown, bluish spot in between. Ocular area strongly elevated; thoracic furrow distinct. PME–PME, 115 Mm; PME diameter, 125 Mm; PME–ALE, 150 Mm; AME–AME, 20 Mm; AME diameter, 20 Mm. Sternum wider than long (0.80/0.65), unmodified. Chelicerae with patch of ~15 short modified hairs on each side ( Fig. 155 shows a male from near Polo, with slightly more and larger modified hairs). Palps as in Figure 154 , coxa with retrolateral apophysis, femur with rounded proximal and pointed distal ventral apophyses; procursus without dorsal spine-like process, bulb with large, weakly curved apophysis and complex membranous and sclerotized subdistal projections. Femur 1 with prolateral row of ~30 short spines, not reaching tip; femur 2 with three rows of spines (~ 25 in prolateral row, ~ 10 in prolateroventral row, ~ 20 in retrolateroventral row; the latter two reaching tip); all femora with many short vertical hairs; curved hairs on tibiae and metatarsi 1–3 (most on legs 2); retrolateral trichobothrium of tibia 1 at 12%; prolateral trichobothrium missing on tibia 1, present on all other tibiae. Tarsus 1 with more than 20 pseudosegments, indistinct.

Variation: Number of spines on femora 1 and 2 varies considerably; prolateral rows may be missing entirely; white lines on abdomen variably distinct, often rather light bluish; the male from near Polo has slightly larger and more modified hairs on the chelicerae than the type. Tibia 1 in 12 other males: 5.5–8.4 (mean 7.3).

Female: In general, similar to male, but sternum with pair of distinct projections on posterior margin ( Figs 49, 50 ). Tibia 1 in 25 females: 4.9–6.4 (mean 5.7). Epigynum, distinctively shaped sclerotized plate, five brushes/combs of stronger hairs (one median frontally and two lateral pairs); dorsal view as in Figures 72 and 156 . Females from near Polo differ slightly in the shape of the epigynum ( Fig. 49 ), but have indistinguishable internal genitalia.

Distribution: Known only from Barahona Province, Dominican Republic ( Fig. 199 ).

Material examined: Dominican Republic: Barahona Prov., north-west Paraíso, 1♂, holotype above; same data: 9♂, 12♀ and three juveniles ( ZFMK, Haiti 58, 58a); forest north-west of Paraíso, about 500 m from type locality, 180 m a.s.l., near ground, 7 December 2007 (B.A. Huber), 3♂, 8♀ and seven juveniles ( ZFMK, Haiti 52); same data, 1♀ and three juveniles, in pure ethanol ( ZFMK, Haiti 101); south of Barahona (18°01.9 ′ N, 71°08.4 ′ W), forest along brook, 60–150 m a.s.l., 18 November 2005 (B.A. Huber), 1♂ and 7♀ ( ZFMK, DR 70 ) ; near Polo (18°06.8 ′ N, 71°16.2 ′ W), forest with plantations, 850 m a.s.l., 17 November 2005 (B.A. Huber), 1♂, 2♀ and two juveniles ( ZFMK, DR 64 ) .

Figures

Figure 199. Known distributions of representatives of the southern paleoisland group.

Figures 38–62. Epigyna in ventral view. 38. M. femoratus (arrow points to frontal sclerite). 39. M. jima sp. nov. 40. M. angulatus sp. nov. 41. M. kiskeya sp. nov. 42. M. toma sp. nov. 43. M. vittatus (arrow points to distinctive posterior sclerite). 44. M. makandal sp. nov. 45. M. fuscus. 46. M. epepye sp. nov. 47. M. seguin sp. nov. 48. M. roumaini sp. nov. 49, 50. M. enriquillo sp. nov. from near Polo (49) and from south of Barahona (50) (arrows point to sternum apophyses). 51, 52. M. tiburon sp. nov. 53. M. leprete sp. nov. 54. M. macaya sp. nov. 55. M. bachata sp. nov. 56. M. cuadro sp. nov. 57. M. pelejil sp. nov. 58. M. mango sp. nov. 59. M. berac sp. nov. 60. M. palvet sp. nov. 61. M. miri sp. nov. 62. M. paraiso sp. nov.

Figures 63–82. Cleared and stained epigyna in dorsal view. 63. M. femoratus. 64. M. jima sp. nov. 65. M. toma sp. nov. 66. M. vittatus. 67. M. makandal sp. nov. 68. M. fuscus. 69. M. epepye sp. nov. 70. M. seguin sp. nov. 71. M. roumaini sp. nov. 72. M. enriquillo sp. nov. 73. M. tiburon sp. nov. 74. M. leprete sp. nov. 75. M. macaya sp. nov. 76. M. mariposas sp. nov. 77. M. bachata sp. nov. 78. M. cuadro sp. nov. 79. M. pelejil sp. nov. 80. M. mango sp. nov. 81. M. berac sp. nov. 82. M. miri sp. nov.

Figures 154–160. Diagnostic characters. 154–156. Modisimus enriquillo sp. nov. 154. Left palp, retrolateral view. 155. Male chelicerae, frontal view. 156. Cleared epigynum, dorsal view. 157–160. Modisimus tiburon sp. nov. 157. Left palp, retrolateral view. 158. Male chelicerae, frontal view. 159, 160. Cleared epigynum, dorsal (159) and ventral (160) views. Scale bars: 0.3 mm.

Figures 17–37. Habitus photos of males (except 33), showing typical and distinctive characters. 17, 18. M. femoratus. 19. M. jima sp. nov. 20. M. kiskeya sp. nov. 21, 22. M. angulatus sp. nov. 23, 24. M. epepye sp. nov. 25. M. mango sp. nov. 26. M. cienaga sp. nov. 27–29. M. seguin sp. nov. (arrows point to callus-like area). 30–34. M. vittatus. 35. M. palvet sp. nov. 36. M. berac sp. nov. 37. M. paraiso sp. nov.