| Abstract: | Five new species of the genus Bogidiella Hertzog (Crustacea, Amphipoda, Gammaridae) are described from subterranean waters of Mexico and Guatemala. They have been collected during the biospeleological researches in southern Mexico and Guatemala (1973, 1975) promoted and financed by the Accademia Nazionale dei Lincei.
B. orchestipes n. sp. (Mexico, Chiapas, well at S. Cristobal de las Casas) is a medium sized (3-4 mm) phreatic species, with lenticular organs on the pereopods III-VI, related to B. holsingeri Ruffo and Vigna, 1973, in the shape of the gnathopods (sinuate palmar edge and a single palmar spine), pleopods, telson and mouth appendages (maxilla I with pluridentate spines on the outer lobe, maxilla II with elongated lobes, maxillipeds with second article of the palpus broadened), but easily distinguishable for the elongated body, with mesosomites longer than their height, coxal plates distanced, the posterior edge of the basis of gnathopods with 3 long setae, the carpus of the pereopod VII strongly dilated, the uropod I differentiated in the male, with 2 rasp-like spines on the outer ramus.
B. pasquinii n. sp. (Guatemala, Huehuetenango, S. Eulalia, Cueva de los Resadores) is a cave-dwelling species, with lenticular organs on the pereopods III-VI, very similar to B. holsingeri Ruffo and Vigna, 1973, in the shape of buccal appendages, gnathopods, pleopods and telson, but distinguishable for the smaller size (2,2-2,8 mm), the posterior edge of the basis of gnathopods with 3 long setae, the dactylus of pereopods III-IV longer than half the length of propodus, with elongated claw, and especially for the shape of the uropod I of the male, with the outer ramus small and at right angle with the inner one, provided with a very long basal spine, curved at semicircle and denticulate at the end.
B. vomeroi n. sp. (Mexico, Chiapas, Sitala, Cueva de Chanchaniptic) is a small sized (2,2-2,6 mm) cave-dwelling species, similar to B. holsingeri Ruffo and Vigna, 1973, for lenticular organs, buccal appendages, gnathopods, pleopods and telson, but with the uropod I not differentiated in the male; the gnathopods I and II have similar propodites, and only 1 long seta on the posterior edge of the basis; pereopod VII has merus and carpus dilated. We refer, uncertainly, to the last species also two small (2 mm) femal specimens found in another cave (Mexico, Chiapas, El Porvenir, Sumidero de Canada) from an isolated karst area at high altitude of southern Chiapas.
B. niphargoides n. sp. (Mexico, Oaxaca, well at Etla) is a medium sized (4 mm) phreatic species, not related to the previously known species, with mesosomites higher than their length, large coxal plates, small lenticular organs on the basis of the pereopods III-VI; maxillae I with pluridentate spines on the outer lobe; antennae I longer than half the total length; gnathopods with 3-4 long setae on the posterior edge of the basis and with large, ovoidal propodus; palmar edge with a great number of spines; pereopods slender and elongated; pleopods and uropods not differentiated in the male.
В. michaelae n. sp. (Mexico, Oaxaca, well at Etla) is another phreatic species of medium size (3 mm), not related to the previously known species; male unknown; without lenticular organs on the pereopods; maxillae I with pluridentate comb-like spines on the outer lobe; gnathopods with only 1 long seta on the posterior edge of the basis and 1 palmar spine; carpus of gnathopod II long as propodus, this one small, subrectangular, with palmar edge short and little inclinated; pereopods stout, the VII with merus, carpus and propodus dilated; uropod I with the outer ramus shorter than inner, uropod III with dilated rami; telson distally not incised.
The previously known species from Mexico, B. tabascensis Villalobos, 1961; B. sbordonii Ruffo and Vigna, 1973, and B. arganoi Ruffo and Vigna, 1973, have been found in some new localities; all these show some differences from the typical populations. B. tabascensis from Chiapas (Ocosingo, Cueva de Chital n. 2) differs from specimens of Tabasco for the shape of the differentiated spines of the pleopods I and II of the male and for the slender pleopods; B. sbordonii from Central Chiapas (S. Cristobal, Cueva de la Planta n. 3 and Altamirano, Cueva de los Chivos) differs from the typical specimens from the area near Ocozocoautla in the shape of the differentiated spines of the pleopod I of the male and in the not differentiated spine of the pleopod II; B. arganoi from the well at Etla (collected together B. niphargoides n. sp. and B. michaelae n. sp.) has some characters different from the only one type specimen from Paraje Nuevo (Veracruz, Cordoba). These specimens are described and figured. Presumably they may belong to different subspecies; at present we do not refer them to any fixed taxonomical status, for lack of knowledge in the geographical variation of these species.
Other single specimens of the genus Bogidiella from phreatic waters of wells in Oaxaca Lambityeco), Puebla (Tehuacan) and Campeche (Campeche), not suitable for complete study, lacking in appendages, are also listed.
In the last part of this work, the status and the relationships of the Central American Bogidiella are discussed; as far as our present knowledge, two groups of species could be established: the tabascensis-sbordonii-group (without lenticular organs and with sexual dimorphism in differentiated spines on pleopods of the male and the holsingeri-pasquinii-orchestipes-vomeroi-group (with lenticular organs on pereopods III-V I, palmar edge sinuate and only I palmar spine on propodus of gnathopods, and with sexual dimorphism in the uropod I of the male, however vomeroi lacks in this character). В. arganoi may be related to the last group, in sexual dimorphism in the uropod I of the male and in similar shape of mouth appendages etc.; on the contrary, B. niphargoides and B. michaelae are well isolated species among the Central American ones.
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