Etienneus africanus ( Hentschel, 1899 )

Huff, Jeremy C. & Prendini, Lorenzo, 2009, On the African Whip Scorpion, Etienneus africanus (Hentschel, 1899) (Thelyphonida: Thelyphonidae), with a Redescription Based on New Material from Guinea-Bissau and Senegal, American Museum Novitates 3658, pp. 1-16 : 6-13

Etienneus africanus ( Hentschel, 1899)

Figures 1–10; table 1

Hypoctonus africanus Hentschel, 1899: 430 , 431; Werner, 1935: 479; Cooke and Shadab, 1973: 1– 6, figs 1, 2, 7, 10; Rowland and Cooke, 1973: 65.

Labochirus africanus ( Hentschel, 1899) : Gravely, 1916: 64; Mello-Leitão, 1931: 21.

Hypoctonus clarki Cooke and Shadab, 1973: 1–3 , 6– 11, figs. 3 , 4, 8, 12; Rowland and Cooke, 1973: 65 (synonymized by Heurtault, 1984: 122).

Etienneus africanus ( Hentschel, 1899) : Heurtault, 1984: 115–122, figs. 1–11; Haupt and Song, 1996: 43; Harvey, 2002: 363, 2003: 61; Giupponi and Vasconcelos, 2008: 18.

TYPE MATERIAL: Hypoctonus africanus Hentschel, 1899 : SENEGAL: 1843, E. Ehrmann, 4 ♀ syntypes ( MZS). According to the original description, two of the syntypes were collected in Senegal and two in Algeria (erroneous). It is also unclear whether E. Ehrmann was the original collector. Hypoctonus clarki Cooke and Shadab, 1973 : THE GAMBIA: Western Division: Yundum [13 ° 24 9 N 16 ° 42 9 W], 1.ix.1956, C. R. Wallace, holotype J ( BMNH), 1951, M.H. Roth, 2 J paratypes ( BMNH).

DIAGNOSIS: As for genus.

DESCRIPTION: The following description is based on 2 J and 6 ♀ deposited in the AMNH (figs. 1, 2, 4–10; table 1).

Total length: Maximum adult length, measured from anterior margin of carapace to posterior edge of pygidium (segment XII), 30.42 mm (J), 35.35 mm (♀) (table 1).

Color: Carapace and tergites, dorsal surfaces, brown to dark reddish brown (figs. 1, 2). Sternites I–VII, ventral surfaces, orangebrown, lateral edges, brown; VIII, surfaces, uniformly brown. Pygidium, dorsal and ventral surfaces, reddish brown. Flagellum, dorsal, lateral and ventral surfaces, reddish brown, covered with reddish macrosetae. Pedipalp trochanter, femur, patella and tibia, dorsal and ventral surfaces, reddish brown; internal surfaces with reddish macrosetae. Pedipalp basitarsus, dorsal and ventral surfaces, dark brown proximally, black distally. Leg I, segments, reddish brown; II–IV, coxa and trochanter, orange-brown, other segments reddish brown.

Chelicerae: Movable finger longer than fixed finger, hinged along dorsal edge, with dense brush of reddish macrosetae on ental and ectal surfaces (fig. 4); manus with fewer, anteriorly directed, short, stout macrosetae on internal and external surfaces; fixed finger with short tooth basally. Chelicera of female larger than male.

Prosoma: Carapace, dorsal surface, finely and densely granular, granulation coarser below and immediately posterior to lateral ocelli (fig. 5A); posterior fovea obsolete; epistoma present; without carina between median and lateral ocelli; median ocular tubercle situated 1.12 mm from anterior carapace margin (table 1), distance between ocelli 0.78 times ocular diameter; lateral ocelli, anterior ocellus nearly twice diameter of median and posterior ocelli. Sternum with median longitudinal suture (fig. 5B).

Pedipalps: Surfaces very smooth, shiny, finely punctate, covered with short macrosetae internally (fig. 6). Coxa, external surface with vertical wrinkles, ventral surface smooth; apophysis with one tooth distally, covered in long macrosetae. Trochanter smooth, as long as (♀) or longer than (J) wide; dorsointernal surface with five teeth, fourth from terminal twice length of remaining four (♀), or with

Fig. 5. Etienneus africanus ( Hentschel, 1899) , ♀ (AMNH). A. Carapace, dorsal aspect. B. Sternum, ventral aspect, showing median longitudinal suture. C. Pygidium, dorsal aspect, showing ommatoids. Scale bars 5 1 mm.

Fig. 6. Etienneus africanus ( Hentschel, 1899) , J and ♀ (AMNH), pedipalps. A. J, dorsal aspect. B. J, ventral aspect. C. ♀, dorsal aspect. D. ♀, ventral aspect. Scale bars 5 2.5 mm.

Fig. 7. Etienneus africanus ( Hentschel, 1899) , ♀ (AMNH), leg I. A. Basitarsus and telotarsus, lateral aspect, showing uniformally short setae along ventral surface. Scale bar 5 1 mm. B, C. Telotarsus, terminal segment, anterior aspect, showing curved, subconical projection. Scale bars 5 100 m m. D. Tibia, distal end, lateral aspect, showing relative positions of two trichobothria. Scale bar 5 100 m m. E. Tibial trichobothrium, dorsal aspect. Scale bar 5 50 m m.

only one pronounced tooth, others greatly reduced or granular (J); internal surface with granules and reduced teeth (♀) or few, sparse granules (J); ventrointernal surface with three teeth, proximal tooth greatly reduced. Femur one and a half times longer than (♀) to almost twice (J) length of trochanter; external surface smooth; dorsal, internal, and ventral surfaces sparsely to densely granular; dorsointernal surface with (♀) or without (J) tooth;

Fig. 8. Etienneus africanus ( Hentschel, 1899) , J and ♀ (AMNH), sternites II–IV, showing genital opercula. A. J, ventral aspect. B. J, dissected and cleared, dorsal aspect. C. ♀, ventral aspect. D. ♀, dissected and cleared, dorsal aspect. Scale bars 5 1 mm.

ventrointernal surface with tooth. Patella almost as long as femur; dorsal and external surfaces smooth; external surface with median longitudinal indentation; dorsointernal surface with granules and with (♀) or without (J) short tooth proximal to apophysis; internal and ventral surfaces sparsely granular; ventrointernal edge with one prominent (♀) or vestigial (J) tooth distally. Patellar apophysis twice as long as (♀) or slightly longer than (J) basal width; internal edge with serrate row of teeth; external edge with (♀) or without two teeth (J). Tibia as long as femur, swollen (J) or unmodified (♀); dorsal, external, and ventral surfaces smooth; internal surface smooth proximally, densely granular distally with macrosetae situated at base of most granules; dorsointernal edge with row of prominent (♀) or vestigial (J) teeth; ventrointernal surface with one tooth distally. Fixed finger, dorsal edge smooth (J) or with row of teeth (♀); ventral edge with serrate row of denticles. Basitarsus (movable finger), dorsal margin with serrate row of denticles; ventral margin with serrate row of teeth.

Legs: Leg I, basitarsus and telotarsus, tarsomeres II and III equal in length; IV slightly longer than V; V, VI, and VIII equal in length; VII shorter than VIII; IX longest, terminating in dorsally curved, subconical projection (♀) (fig. 7A–C); III– IX, ventral surfaces each covered with dense, uniformly

Fig. 9. Etienneus africanus ( Hentschel, 1899) , ♀ (AMNH), spermatheca and operculum showing the two seminal receptacles. Scale bar 5 1 mm.

short macrosetae (fig. 7A). Legs II–IV, basitarsus with two ventrodistal spurs. Leg IV, tibia with one ventrodistal spur. Leg I with two trichobothria (fig. 7D, E); II–IV with one; trichobothria situated distally on tibia.

Opisthosoma: Tergites, surfaces, finely granular; I–IV divided by median longitudinal suture; V –VII (J) or V – IX (♀) partially suturiform; X not divided laterally by suture (pleuron); XII (anal) with pair of large, oval, laterally compressed ommatoids angled anteromedially in dorsal aspect (fig. 5C). Sternite II (genital) (fig. 8A, C) smooth, with two shallow lateral depressions (♀) or shallow folds along posterior edge (J), posterior median margin lobate (J) or sublinear (♀) (fig. 8A, C); III and IV (J) or IV (♀) divided by median longitudinal suture; V partially suturiform (♀ only). Pygidial flagellum without flagellar organs; each segment with two to

Fig. 10. Etienneus africanus ( Hentschel, 1899) , J (AMNH), hemispermatophore. A. Ental aspect. B.

Ectal aspect. Scale bar 5 1 mm.

TABLE 1 Etienneus africanus ( Hentschel, 1899) , selected measurements (mm) of seven specimens from Senegal (AMNH)

four very long macrosetae. Seminal receptacles spherical, directed posteriorly (fig. 9).

Hemispermatophore: Sperm package Jshaped with enlarged tip and reservoir; elongated jointlike stem connecting tip with hooked end (fig. 10).

Sexual dimorphism: The adult male and female differ in several characters. The spination and granulation of the pedipalps are more pronounced in the female; the pedipalp patellar apophysis is greatly reduced in the male; the dorsally curved, subconical projection of leg I, tarsomere IX of the female is absent in the male; the paired shallow lateral depressions on sternite II of the female are absent in the male; sternites II and III are separated medially by a subcutaneous sclerotized surface in the female but unmodified in the male (fig. 8B, D).

ADDITIONAL MATERIAL: THE GAMBIA: Central River: Sapu Agricultural Station , 180 mi. up river [13 ° 33 9 N 14 ° 54 9 W], 1968, G.C.H. Smith, 1 ♀ ( BMNH) , 1 ♀ tritonymph ( AMNH) . GUINEA: Dr. Mallaud, 1 J ( MNHN) . GUINEA-BISSAU: Bafata: Bambadinca, 19 km S, 11 ° 53 9 03.9 0 N 14 ° 50 9 08.5 0 W, 38 m, 30.vi–1.vii.2005, J. Huff and V. Vignoli, 1 ♀, 1 J tetranymph, 1 J, 2 ♀ tritonymphs. SENEGAL: Région de Casamance : Djibelor [12 ° 33 9 10 0 N 16 ° 19 9 20 0 W], J. Etienne 15.vii.1982, 1 ♀ ( MNHN) ; Djibelor, Centre de recherches agronomiques Zuiginchor [12 ° 33 9 10 0 N 16 ° 19 9 20 0 W], J. Etienne and Dr. Mallaud, 3.viii.1982, 11 J (1 dissected) ( MNHN) . Région de Kolda: Sefa [12 ° 47 9 09 0 N 15 ° 33 9 02 0 W], A. Diop, 1 J ( MNHN) , J. Etienne, 15.ii.1981, 4 ♀, 5 juv. (2 dissected) ( MNHN) . Région de Tambacounda: Kedougou [12 ° 33 9 N 12 ° 11 9 W], P. de Miré and D. Pluot- Sigwalt, x.1981, dans litière de forêt, 4 juv. ( MNHN) ; Kedougou, 3 km W on road to Salemata , 12 ° 33 9 10.6 0 N 12 ° 13 9 39.4 0 W, 126 m, 4.vii.2005, J. Huff and V. Vignoli, 2 J, 5 ♀, 3 J tetranymphs, 2 J, 1 ♀ tritonymphs, 4 J, 3 ♀ deutonymphs, 1 protonymph ( AMNH) .

NATURAL HISTORY: Newly collected specimens were taken from under rocks or logs in small forest fragments ( fig. 11 ). The soil under forest bordered by a flood savanna, and thus considerably more humid than other forests in the region, five specimens were located under rocks and logs in approximately four hours of searching ( fig. 11A ). During this period, Senegal experienced heavy rains. One day after returning to Senegal from Guinea- Bissau, 21 specimens, including adults and juveniles, were collected under rocks in just two hours, in a small, humid patch of forest ( fig. 11B ). The forest in which these specimens were collected was only about 100 m 2 in area, and surrounded by dry grassland with no tree canopy, suggesting that E. africanus was concentrated in the forest because it was the only suitable habitat in the immediate area.

the rocks or logs where specimens were found was more humid and less compacted than that under rocks or logs in direct sunlight, where specimens were not found. The behavior of E. africanus appears to be similar to that of other whip scorpion species that inhabit regions with distinct wet and dry seasons. During the dry season, individuals burrow to reach moisture and remain dormant below the surface until arrival of the first rains, whereupon they reemerge to the surface. In the summer of 2005, the rains in Guinea-Bissau were over a month late, and the substrate, even under logs and in the leaf litter, was extremely dry. No specimens were collected in five days of intense searching by several individuals in a forest where, according to local collectors and photographs, specimens are commonly found in the rainy season. Approximately 20 km south, however, in a

Figures

Fig. 3. Map of West Africa, plotting the known locality records of Etienneus africanus (Hentschel, 1899).

Fig. 11. Subtropical forest habitat of Etienneus africanus (Hentschel, 1899). A. Guinea-Bissau: 19 km S of Bambadinca. B. Senegal: 3 km W of Kedougou on road to Salemata.