Redefinition Of Pelopsis (Acari: Oribatida: Mycobatidae), With Description Of Pelopsis Baloghi Sp. N. From Costa Rica Author Behan-Pelletier, V. Author Eamer, B. Author K. W text Acta Zoologica Academiae Scientiarum Hungaricae 2003 2003-03-12 49 1 5 15 journal article 105945 10.5281/zenodo.5731728 09edee5a-35af-4b50-9a41-768a82d5e074 2064-2474 5731728 Pelopsis baloghi sp. n. ( Figs 1–14 ) Material examined – Holotype : adult m . Costa Rica : Heredia , Estación Biologica La Selva , Swampo Experimentale , 10°26’N 84°01’W , 9 June 1997 ( V . BEHAN- PELLETIER), aquatic vegetation and debris, deposited in the Acari collections of INBio , Insitituto Nacional de Biodiversidad , Santo Domingo , Costa Rica . Paratypes : 10 with same data as holotype; 2 with same data as holotype , except 17 May 1995 , from saturated soil . Paratypes deposited in the Canadian National Collection of Insects and Arachnids , Agricultureand Agri-Food Canada , Ottawa , Canada , INBio , thecollections of R . A. N ORTON and the Hungarian Natural History Museum, Budapest . Etymology – This species is named in honor of Professor JÁNOS BALOGH for his outstanding contributions to knowledge of Oribatida worldwide. Figs 6–9. Pelopsis baloghi , scanning electron microscope images of adult female: 6 = lateral aspect, with detail of striate integument of notogaster indicated by arrow; 7 = dorsal aspect; 8 = dorsolateral aspect of anterior third, with lamellar seta indicated by arrowhead; 9 = dorsolateral aspect of anterior of notogaster and posterior of prodorsum Diagnosis. Adult – Total length 420–508 µm; integument striate on notogaster, pteromorphs, epimeres, ventral, genital and anal plates and mentum; lamella developed as very strong ridge, 91–101 µm long; lamellar setae arising anteroventrally on lamellar cusps; seta in 98–127 µm long; sensillus 60–72 µm long, with heavily barbed, long clavate head; notogastral setae very short, thin, at most 6 µm long. Description. Adult: Measurements – Mean total length: females ( n = 10) 454 µm (range 420–508); males ( n = 3) 441 µm (range 422–499). Mean notogastral width: females ( n = 10) 304 µm (range288–336), males ( n = 3), 303 µm (range288–336). Integument. Microtuberculate on prodorsum, tutorium, genal process, pedotectum I, anterolaterally on epimere I, and on leg segments. Striate on notogaster, pteromorphs, epimeres, ventral, genital and anal plates, mentum, abaxially on femora III and IV and dorsodistally on trochanters III and IV. Prodorsum – Rostral margin strongly concave medially, with 2 lateral dens ( Figs 11, 12 ). Seta ro 53–58 µm long, weakly barbed, acuminate ( Figs 1 , 12 ). Lamella developed as very strong ridge, 91–101 µm long, almost parallel ( Figs 1 , 9 ), ridge undulating in bothridial region ( Fig. 9 ); lamellar cusp 17–19 µm long, parallel ( Fig. 8 ). Seta le barbed, 19–24 µm long, arising anteroventrally on lamellar cusp, directed anterolaterally, extending beyond tip of rostrum ( Figs 10, 11 ). Seta in 98–127 µm long, inserted on transverse ridge, dorsoventrally flattened, strongly barbed dorsally and laterally, narrow proximally and distally, broadening medially, with conspicuous medial and lateral dens about 24 µm long and small dens between them about 4–7 µm long ( Figs 1 , 10 ). Mutual distance of setal pairs ro-ro , le-le and in-in , about 60 µm, 22–24 µm and 29–31 µm, respectively. Seta ex barbed, about 35 µm long. Sensillus 60–72 µm long, with heavily barbed, long clavate head, rounded distally, curved anteromedially ( Figs 1 , 8 ). Dorsal apodemes (dorsophragmata) well separated basally ( Fig. 1 ). Porose area Ad circular and medial to bothridium. Lateral aspect of prodorsum – Genal process triangular, tapered to point, with well-developed ridge( Fig. 12 ). Tutorium, including cusp, about 112 µm long, distinctly pointed distally, ( Figs 3 , 12 ), with longitudinal ridges dorsoproximally ( Fig. 9 ); tutorial cusp about 36 µm long. Tutorium strongly curved medially forming concise fit with ridge on genal process ( Figs 11, 12 ). Pedotectum I with strongly concave dorsal margin, with dorsal insertion posterior of seta ex ( Fig. 3 ). Custodium about 12 µm long ( Fig. 14 ). Circumpedal carina strongly developed, curving to level of setae 3b ( Figs 3 , 13, 14 ). Notogaster – Longer than wide, ratio 1.2:1. Lenticulus well-developed, subrectangular in shape ( Fig. 1 ). Notogastral striae with thumb-print pattern, directed longitudinally on anterior third of notogaster and transversly posterior to level of saccule S1 ( Fig. 6 ). Notogastral setae very short, thin, at most 6 µm long ( Fig. 1 ). Saccules small, clearly evident, Sa positioned anterior of seta lm , S1 posterolateral of lp , S2 midway between setae h 3 and h 2 , S3 lateral of seta h 1 ( Fig. 1 ). Ventral region – Epimere I tuberculate anterolaterally, remainder of epimeres I to IV striate ( Figs 11, 12 ). Epimeral setae weakly barbed, tapered, 3b longest setae, about 34 µm, other epimeral setae 16–24 µm long. Genital plates with longitudinal striae, anal plates with predominantly transverse striae, striae on ventral plate predominantly longitudinal ( Fig. 2 ). Genital setae about 17 µm, g 1 and g 2 weakly barbed, positioned on anterior margin of plate ( Fig. 13 ). Aggenital, anal and adanal setae smooth, thin, about 6–10 µm long. Postanal porose area not evident. Gnathosoma – Mentum with predominantly longitudinal striae; gena with striae directed anteromedially ( Figs 2 , 11 ). Axillary saccule of subcapitulum about 10 µm long. Legs – Setation (I-IV): trochanters, 1–1–2–1; femora, 5–5–2–2; genua 3(1)–3(1)–1(1)–2; tibiae, 4(2)–4(1)–3(1)–3(1); tarsi, 20(2)–15(2)–15–12 ( Figs 4, 5 ). Tibia I with small anterodorsal dens rior of circumventral groove indicated by arrowhead Figs 10–14. Pelopsis baloghi , scanning electron microscope images of adult female: 10 = dorsal aspect of prodorsum and anterior of notogaster; 11 = ventral aspect of gnathosoma and epimere I; 12 = frontal aspect of gnathosoma and rostrum; 13 = ventral aspect of ventral plate and genital plates, circumpedal carina indicated by arrowhead; 14 = lateral aspect of notogaster and ventral plate, ante- ( Fig. 4 ). Tibiae I and II indented abaxially ( Fig. 10 ). Femur II with ventral ridge and ventral projection, with seta bv” positioned abaxial to ridge ( Fig. 5 ). Tibia and tarsus II with dorsal ridge; tarsus II with two tandem dorsal spines abaxial of solenidia ( Fig. 5 ). Trochanters and femora III and IV with ventral carina and ridge; femora III and IV and trochanter IV with striae abaxally. Tibia and tarsus IV thickened dorsally; dorsal integument of tibia and tarsus III not thickened. Remarks – The presence of dens dorsally on tarsus II is one of the character states used by HAMMER (1961) to separate Pelopsis bidentatus from thetypespe - cies, Pelopsis bifurcata . Neither EWING (1909) , in theoriginal description of the type species, or WOOLLEY (1958) who redescribed the species, noted dens dorsally on tarsus II. Dens are not evident on a cotype slide specimen of P. bifurcata that we have examined. However, variation in this character state in specimens from North America argues for caution in its use as a key character. Adults of Pelopsis baloghi though similar to the two other described species in the genus, can be easily distinguished on the basis of character states outlined in the following key.