) Historia naturalis bulgarica, 11, 2000: 65-72 Studies on Erythraeoidea (Acari: Prostigmata) from Africa. The genera Cecidopus and I. Caeculisoma from Nigeria (Erythraeidae: allidosomatinae Petar BERON Iiltroduction During my stay in Nigeria (1976 - 1979), I had the opportunity to collect some mites (among many other animals), including a number of species of the superfamily Erythi'aeoidea. Both families of this superfamily (Erythraeidae and Smarididae) are inadequately known in Afnca and poorly studied in Nigeria. Thebulkofthe mateiialwas collectedin Plateau Statefromthefollovsdngsites: 1. Jos - mainly under stones and in leaflitter in town and in Jos WildUfe Park (alt. 1300 - 1350 m, hilly savanna with rocky outcrops). Cool and humid area (rainfall over 2000 mm per year), the dry season lasting from October to March and rainy season from April to September. 2. Wase Rock Game Reserve - small protected area (0,96 km''^) around a high volcanic plugrisingsheer above the sui'roundingplain close to Wase town. Grass and stones at the rock base. 3. Pandam Wildlife Park - thick savanna forest (partly flooded) around Lake Pandam, alt. ca. 130 m, area 363 km- (SiKES, 1974). 4. Pai River Game Reserve - the most extensive (2124 km^) ofall the protected areas in Plateau State, lowland Sudan savanna bythe river Pai, high grass being burned during the dry season. Descriptions Tribe Callidosomatini Only one of the 3 genera forming the tribe Callidosomatini is known from Africa - CaeculisomaBerlese. This genus has been reported from Ai'gentina, New 65 Fig. 1-3. Caeculisoma haussa sp. .: 1 - Crista, 2 - Palp, 3 - LegI Guinea, Australia, Indonesia, Marquesas Islands, Bhutan (unpublishedj and DR Congo. With the exception ofthe Bhutan find, all other species ofthis genus have been described from the Southern Hemisphere. Only one species has been published from Africa {Caeculisoma afruni Cooreman, 1958 from Kivu, formerly Zaire, now DR Congo). I have foundinnorthern Nigeria a representative ofanewspecies ofthegenus Caeculisoma - the first to be described from the Northern Hemisphere. Caeculisoma haussasp. n. Material. 1 9 ad. (holotype), Maiduguri, Northern Nigeiia, 25.9.1976. The specimen is preserved in the collection of the National Museum of Natui'al History, Bulgarian Academy of Sciences, Sofia. 66 Fig 4-7. Caeculisoma haussa sp. .: 4 - Leg11, 5 - LegIII, 6 - LegIV, 7 -Anogenital area 67 Fig. 8 -13. Cecidopus nigeriae sp.n.: 8 - Crista, 9 - Genital area 10 - Leg I, 11 - Palp, 12 Leg II, 13 - Leg IV 68 , Description. Palp. Femui' 180 jim long, genu 100 tibia 50 jim, tarsus 75 1. The shape ofthe palp similar to that of C. afniniCooreman, but more robust. Proximal seta offemur very long.(moi'e than half ofthe length offemur). Dorsum. Idiosoma long 1790 Idiosomal setae (Fig. 1) vary considerably in length (30-75 fim), but are not oftwo clearly distinct types. Crista 700 l,ong, distance between the bases of anterior and posterior sensilla (ISD) 405 distance between the base of posterior sensilla and the posterior end of crista 230 fim, Anterior and posteiior sensillae broken. On the anterior sensillary area 6 setae (other than the sensillae), 70-110 ^im long. The first 6 sensillae flankingthe crista (behindthe anterior sensillary area), 3 on each side, are very similar in shape and length to the setae on the anterior area (95 - 1 100 long). , Inner diameter ofthe eye is 50 distance between its center and the ciista i,s 180 |iim, distance from its center to the base ofthe right anteiior s.ensilla is 320 from its center to the base of the right posterior sensilla - 250 The point where the axis connectingboth eyes crosses the cristais 265 from the anterior sensillae and 145 from the posterior sensillae. . Venter. Simple, uniform setae with average length 20-30 ): Legs. Length ofleg segments (in Leg 1 - bf = 200; tf = 305; g = 275; ti = 305; ta = 240 Leg II - bf = 115; tf = 130; g = 215; ti = 195; ta = 130 Leg III - bf = 125; tf = 150; g = 240; ti = 225; ta = 130 Leg IV - bf = 150; tf = 255; g = 320; ti = 280; ta = 135 With the mite genus Caeculisomathe legsetae are very peculiar and complex. With the new species C. haussa, as well as with the only other species adequately described (C. afruni Cooreman), on each segment are found setae of several types, especially on the femui', genu and tibia. I have marked them on the figui'es with the same letters as on the drawings ofCoorkman (1958), in ordertofacilitate the comparison. Setae of type b are scarce on C. haussa. On trochanter I only setae oftype aare present. As with C. a/rum, short spines are situated distally of the tubercles on genu and tibia. These are described by Cooreman (1958) as: "element sensoriel en forme de cone court". Discussion. Virtually none of the Caeculisoma species has been described and illustrated according to modern standards. These inadequately described species however live in localities far removed from Africa and the chance of coincidence with ouivAfrican speciesissmall. Fortunately, the onlyspeciesknown from Africa has been described in detail by Cooreman (1958). This provides me with the opportunity to compare his Caeculisoma afrum from Congo with the new Caeculisoma haussa from Nigeria (their localities are approximately 2400 km far away from each other). The Nigerian species lives in dry lowland savanna and the species of Cooreman - in the humus ofmountain rain forest at alt. 2200 m in the Kivu Province, DR Congo (Zaire). 69 The twospecies are clearlyrelated. The main distinctive featm"es are asfollows: 1. The anterior sensillary area of Caeculisoma a/rum bears 20 setae, while that of Caeculisoma haiissabears only 7 setae. 2. Despite thesimilarityofthetypes oflegsetae of afrumand haussa, their number and arrangementonthelegs are different. Caeculisomaafrumhas amuch higher number ofall tes ofsetae. Setae type b(in the present publication and in that of CooRi'-MAN, 1958) are more slender by Caeculisoma afrum than by C. haussa. They are present on b/" I of Caeculisoma afrum and are missing in Caeculisoma haussa. Similar differences may be found on all leg segments. 3. The length ratio of leg segments, and the other dimensions, are similar in the two species, but with Caeculisoma afrumthe length oflegsegments is nearly double those of Caeculisoma haussa. Tribe Charletoniini Genus Cecidopus Karsch The genus Cecidopuswas createdbyKarsoh (1879)for a mite form Ceylon (Sri Lanka). This mite {Cecidopus diversipes) has not since been rediscovered or redescribed. The two other species in Asia are C. shyamaeKhot, 1965 from India and qadtiiAhsan et Anwarullah, 1970 from Pakistan. The remaining three (maybe two) species ofthis genus are known from Africa: C. chubbi(Bev\ese, 1914) and C. mitchelli(Hirst, 1924)fromSouthAfiica(synonyms ?, see Sor'rilcoTT, 1961) and C. straeleni Cooveman, 1953 from Congo. Among the mites collected in Nigeiia two specimens were representatives ofa new Cecidopus. Cecidopus nigeriae sp. n. Material. 1 rf (holotype), 1 cf (paratype), both specimens full with eggs, Nigeiia, Plateau State, Wase Rock Game Reserve, under stone, 01.06.1978. Holotype deposited in the mite collection of the National Museum of Natui'al History, Sofia, paratype in the collection of the Royal Museum of Central Africa in Teivuren, Belgium (No 170555). , Description. Palp. Tarsus pyriform, 120 x 90 extending beyond palpal tibial claw. The palpal tarsus ofthe paratype has been drawn, one ofthe tarsi of the holotype being lost and the other mounted in a position unsuitable for measuring and figui'ing. Idiosoma. Dorsum: idioso)mal setae short (18-30 ^tm), both sides of the crista there are two longer (60-70 and more massive setae. Crista long (890 ^an), distance SL = 760 ^im. On the anterior sensillary area 7 setae (holotype) and 4 1 (paratype), 80-175 fim long, and two sensillae 90 long. Distance between the eye center and the middle ofcrista 355 jmi. Venter. Idiosomal setae similar to the dorsal setae, but muchmore slender, 35- 50 long. 70 Legs. I, II, and III with no special features, covered with short, smooth, uniform setae. The most remarkable feature ofthe whole genus Cecidopus is the shape of the telofemui' IV and especially of genu IV - they are greatly enlarged, "clublike". Sowriicorr (1961) has corrected the errors of the formers authors about the right position ofthis "club" on the leg IV. Neither Southcott himself, nor any other recent author seem to have seen many specimens belonging to the genus Cecidopusand probably the present notes contain the first contribution to the knowledge of Cecidopussince 1970. Length of leg segments of C. nigeriae sp. n. - holotype, in (the values of these dimension with C. straeleni are given in brackets, after Cooiieman, 1953): I- bf= 335 (215); tf= 575 (530); g = 590 (540); ti = 640 (560); ta = 370 (400) II- bf= 225 (130); tf= 325 (290); g = 385 (340); ti = 415(350); ta = 255 (215) III - bf= 255 (140); tf= 415 (430); g = 495 (470); ti = 530 (470); ta = 255 (250) IV - bf= 460 (325); tf = 815 (780); g = 770 (740); ti = 865; ta = 320 Discussion. Generally speaking, the new species is bigger than straeleni. Some of the dimensions ofleg segments are close with both species, others differ considerably. The anterior sensory area of C. mitchelli(Hirst) from South Africa bears 12 setae (4-7 with the new species). References Ahsan, M., M. Anwakullam. 1970. A new species of Cecidopu.< ft-om Pakistan (Acarina: Erytlu-aeidae). - PakistanJ. Zool. 2 (1): 47 - 49. CooKivMAN, J. 1953. Notes et observations sur les Acariens. V. - Sur le geni-e Cacidopuf Karsch (Erytlu-aeidae) et sur une espoce nouvelle du genre Percanesthnia Berlese (Canestriniidae). - BuU. Sci. Nat. Belg. 29 (31): 1-12. CoouiOMAN, J. 1958. Acariens du Congo Beige (2e snrie). Note sur le genre CaecLdisoma Berlese, 1888(Acari, Erytlu-aeidae)et descriptiond'une espece nouvelle duCongoBeige. - Revue Zool. Bot. Aft-. 58: 43-53. Kaksch, F. 1879. Arachnologische Beitriige. V. Zur Arachnidenfauna Ceylons. - Z. Ges. Naturw. Berl. 3, 52: 547-562. KnOT, N. 1965. StudiesofIndianErytlii-aeoidea(Acai-ina). SeriesIV. - Mitesofthe subfamily Callidosomatinae Southcott. - Acarologia 7: 63 -78. SiKES, S. K. 1974. Wildlife Conservation, with reference to Benue-Plateau State, Nigeria. - The NigerianField 39 (2): 58-70. Soirriicorr-, R. V. 1961. Studiesonthe SystematicsandBiologyoftheErytlii-aeoidea(Acai-ina), witli a CriticalRevision oftheGenera and Subfamilies. -Aust.J. Zool. 9: 367-610. Received on 21.7.2000 Author's addi-ess: Dr Petal- Beron National Museum ofNatural History 1, Tsar Osvoboditel Blvd Sofia 1000, Bulgaria 71 . Erythraeoidea (Acari: Erythraeidae) Caeculisoma u Cecidopus I. (Erythraeidae: Callidosomatinae) () . . , .. Caeculisoma /iau.<sasp.n. Cecidopus nigeriae ('aeculisoma u Ce.cidopux Caeculisoma- 72