The Arachnid Order Solifugae



Phylogeny of the Solifugae
Keys to FamiliesFamily Ammotrechidae
         Ammotrecha araucana
         Ammotrecha chiapasi
         Ammotrecha cobinensis
         Ammotrecha enriquei
         Ammotrecha friedlaenderi
         Ammotrecha itzaana
         Ammotrecha limbata
         Ammotrecha nigrescens
         Ammotrecha picta
         Ammotrecha stollii



Family Ceromidae
Family Daesiidae
Family Eremobatidae
Family Galeodidae
Family Gylippidae
Family Hexisopodidae
Family Karschiidae
Family Melanoblossidae
Family Mummuciidae
Family RhagodidaeFamily Solpugidae
Catalog of the Solifugae






















Ammotrecha nigrescens Roewer 1934

Ammotrecha nigrescens ►Roewer, 1934: 598, figs 336e, 337f; ►Muma, 1970a: 46, 48, 50, 51, fig. 39; ►Muma, 1976: 26; ►Muma, 1986: 21; ►Muma, 1987: 21; Armas, 1996b: 32; Harvey, 2003: 200; ►Armas, 2004b: 60.
Ammotrecha nigricens: Armas, 1993: 55 (lapsus calami).

TYPES: Guatemala: [locality?], 1894 (Stoll), 1 male; and Costa Rica: San Jose Province - San Jose, [date, collector?], 2 females [?]. [Roewer (1934) indicated that he examined 1 male and 2 females from Guatemala and Costa Rica, including the type) in the British Museum of Natural History, but failed to indicate which of the specimens was the holotype.  Muma later located and characterized the male cited above, but did not designate it as a lectotype.] 

Original description:
Roewer, 1934: 598, figs 336e, 337f:

: "Die Spitze der Flagellum-Spelze reicht nur bis zum zum 1. Vorderzahn nach vorn; unbeweglicher Finger mit 4 lateralen und 3 medialen Wangenzähnen; Gebiß Abb. 337,]; Pedipalpen an Femur und Tibia nur behaart, am Metatarsus ventral mit 5 Paar Dornen und zahlreichen Zylinderborsten (Abb. 336, e); 2. und 3. Metatarsus dorsal mit je einer Längsreihe aus 3 Dornen und ventral wie auch 4. Metatarsus mit je 1.1.2 Dornen.  Färbung der Cheliceren und des Propeltidium dunkel gebräunt, erstere mit 2 noch dunkleren Längsstreifen, Opisthosoma dorsal dunkelbraun, mit vollständiger, breiter weißgelber Mittelbinde; Sternite, Coxen und Malleoli weißgelb, Pedipalpen bis auf den blaßgelben Tarsus ganz dunkelbraun; Korperlänge 12 mm."
Unbeweglicher Finger mit dorsalem, stark chitinisiertem, abgesetztem Buckel, mit 4 lateralen und 3 medialen Wangenzahnen; Gebiß im übrigen wie Abb. 338, b; Pedipalpen behaart, Metatarsus ventral mit 5 Paar Dornen und zahlreichen Zylinderborsten; Bewehrung der Beine und Färbung wie beim ; Körperlänge 18 mm.
♀: "Unbeweglicher Finger mit dorsalem, stark chitinisiertem, abgesetztem Buckel, mit 4 lateralen und 3 medialen Wangenzahnen; Gebiß im übrigen wie Abb. 338, b; Pedipalpen behaart, Metatarsus ventral mit 5 Paar Dornen und zahlreichen Zylinderborsten; Bewehrung der Beine und Färbung wie beim ♂; Körperlänge 18 mm."

[: The tip of the flagellar membrane extends forward only to the 1st anterior tooth; fixed finger with 4 lateral and 3 medial cheek teeth; [dentition fig. 337, e]; Pedipalp only hairy on femur and tibia, with 5 pairs of spines and numerous cylinder bristles ventrally on the metatarsus (fig. 336, e); 2nd and 3rd metatarsus dorsally with longitudinal row of 3 spines and ventrally, as with the 4th metatarsus, each with 1.1.2 spines.  Coloration of the chelicerae and the propeltidium darkly tanned, in the former with 2 even darker longitudinal stripes, opisthosoma dorsally entirely dark brown, with light tan middle patch; sternites, coxae and malleoli pale yellow, pedipalps entirely dark brown up to the pale yellow tarsus; Body length 12 mm.
♀: Fixed finger with dorsal, strongly chitinized , elevated hump, with 4 lateral and 3 medial cheek teeth; dentition as in Figure 338b.  Pedipalps hairy, metatarsus with 5 pairs of ventral spines and numerous cylinder bristles; spination of the legs and coloration as in the male.  Body length 18mm.]  

Fig. 337f - Right male chelicera, mesal view.

Muma (1970b), examined the male type from Guatemala, and provided the following diagnosis:

"Except for the tarsal setal formulae, this species is identical with pale brown typically marked specimens of Ammotrechella stimpsoni (Putnam).  The tarsi of leg III have a spinelike setal formula of 1,2,2,1 and those of leg IV of 2,2-2-2,1 or as for Ammotrecha Roewer.  The metatarsal spinelike setae are, however, somewhat longer than on A. stimpsoni.  Females are unknown.  Figure 39 is of the only chelicera remaining with the type."

Fig. 39 - Right male chelicera, ectal view.

DISTRIBUTION: Guatemala, Costa Rica. 

Published Records: 
Armas 1993: Nicaragua: Una hembra, Corinto, León, marzo 26, 1989, sobre jocote (Spondias purpurascens), A. González, en termitero de Nasutitermes nigriceps (IES).

NOTES: Roewer (1934) attributed this species to Pocock, and reported that he examined specimens in the British Museum (including the type) from both Guatemala and Costa Rica (San Jose, San Jose Province), but provides no specific data for those specimens.  Muma (1970) commented that this species can be considered valid only if the tarsal setal formulae are correct and diagnostic, opining that it otherwise is a junior synonym of Ammotrechella stimpsoni (Putnam).   He did not indicate that he had examined the female specimens cited by Roewer (1934) in the original species description.  Muma (1976) included this species in a list of Western Hemisphere solifuges, recording its distribution as Costa Rica and Guatemala, noting that it was apparently known from two collections (both sexes).  He reported that the male type from Guatemala is in the BMNH, but that the fremale type was not located. Muma (1986, 1987) included this species in a list of families, genera, and species previously recorded from Mexico, Central America, and the West Indies.  He reported that this species has been recorded from Guatemala, Costa Rica (San Jose), and the West Indies, but provided no data regarding those records.  Armas (2004) included the species in a catalog of the solifuges of Central America and the Antilles, reporting its distribution as Guatemala and Costa Rica, and referred to a "macho holotipo" [male holotype] in the BMNH. 
































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