Two new oribatid mite species of the genus Gittella from Ecuador

1 SPIXIANA 36 11-8München, September 2013 ISSN 0341-8391 Two new oribatid mite species of the genus Gittella from Ecuador (Acari, Oribatida, Oppiidae) Sergey G. Ermilov, Dorothee Sandmann, Franca Marian & Mark Maraun Ermilov, S. G., Sandmann, D., Marian, F. & Maraun, M. 2013. Two new oribatid mite species of the genus Gittella from Ecuador (Acari, Oribatida, Oppiidae). Spixiana 36 (1): 1-8. Two new oppiid mite species of the genus Gittella, G. variabilis spec. nov. and G. minor spec. nov., are described from Southern Ecuador. The first new species is morphologically similar to Gittella maxima (Balogh & Mahunka, 1981), however, it differs from the latter by the morphology of sensilli, notogastral setae and epimeral region. The second new species is morphologically similar to Gittella insularis Mahunka, 1998. However, it differs from the latter by the body size, number of interbothridial muscle sigilla and the morphology of rostral and interlamellar setae. The morphology of the gnathosoma is presented in detail for the first time for a species of this genus. Sergey G. Ermilov, Tyumen State University, Tyumen, Russia; e-mail: [email protected] Dorothee Sandmann & Franca Marian, Georg-August-University Göttingen, J. F. Blumenbach Institute of Zoology and Anthropology, Göttingen, Germany Mark Maraun, Georg-August-University Göttingen, J. F. Blumenbach Institute of Zoology and Anthropology, Göttingen, Germany; e-mail: [email protected] Introduction Gittella is a small genus that was proposed by Hammer (1961) with Gittella punctata Hammer, 1961 as type species. At present it comprises five species which are distributed in the Neotropical region: G. ecuadoriensis Ermilov & Kalúz, 2012 from Ecuador, G. flagellata (Mahunka, 1983) from Brazil, G. insularis Mahunka, 1998 from the Antilles Islands, G. maxima (Balogh & Mahunka, 1981) from Paraguay and Panama, and G. punctata Hammer, 1961 from Peru. The generic characters of Gittella proposed by Hammer (1961) have been summarized by Subí as & Balogh (1989), Balogh & Balogh (1992) and Ermilov & Kalúz (2012). The known species of this genus were included in the key given in Ermilov & Kalúz (2012). The main purpose of this paper is to describe and illustrate a sixth and a seventh species of the genus Gittella, collected from Southern Ecuador, under the names G. variabilis spec. nov. and G. minor spec. nov. The morphology of the gnathosoma is presented in detail for the first time for a species of this genus. Materials and methods The Gittella species described in the present paper were collected in Southern Ecuador by F. Marian and D. Sandmann. Specimens were mounted in lactic acid on temporary cavity slides for measurement and illustration. All body measurements are presented in micrometers. The body length was measured in lateral view, from the tip of the rostrum to the posterior edge of the ventral plate, to avoid discrepancies caused by different degrees 2 Table 1. Leg setation and solenidia of Gittella variabilis spec. nov. (same for Gittella minor spec. nov.). Roman letters refer to normal setae (e to famulus), Greek letters to solenidia. Single prime (') marks setae on anterior and double prime (") setae on posterior side of the given leg segment. Parentheses refer to a pair of setae. Leg Trochanter Femur Genu Tibia Tarsus Iv' d, (l), bv", v" (l), σ(l), (v), φ1, φ2(ft), (tc), (it), (p), (u), (a), s, (pv), v', (pl), l", e, ω1, ω2 II v' d, (l), bv", v" (l), σ(l), (v), φ(ft), (tc), (it), (p), (u), (a), s, (pv), l", ω1, ω2 III l', v' d, l', ev' l', σl', (v), φ(ft), (tc), (it), (p), (u), (a), s, (pv) IV v' d, ev' d, l' l', (v), φft", (tc), (p), (u), (a), s, (pv) of notogastral distortion. Notogastral width refers to the maximum width in dorsal aspect. Lengths of body setae were measured in lateral aspect. Formulae for leg setation are given in parentheses according to the sequence trochanter-femur-genu-tibia-tarsus (famulus included). Formulae for leg solenidia are given in square brackets according to the sequence genu-tibia-tarsus. General terminology used in this paper follows that summarized by Norton and Behan-Pelletier (2009). The holotypes are deposited in the Zoological Institute of the Russian Academy of Sciences, St. Petersburg, Russia (ZISP). The paratypes are deposited in the Siberian Zoological Museum, Novosibirsk, Russia (SZMN) and in the personal collection of the first author (PC). Descriptions Gittella variabilis spec. nov. Figs 1-19 Material examined. Holotype: male, Southern Ecuador, 3°58' S 79°50' W, Estación Científica San Francisco, 2000 m a.s.l., upper organic soil layer in mostly undisturbed rain forest, 01.04.2008 (ZISP). – Paratypes: five males and one female in SZMN, and five males in PC, same locality and date as holotype. Diagnosis. Body size 647-680 × 332-356. Surface of notogaster and anogenital region smooth or foveolate. Interbothridial region with two pairs of muscle sigilla. Interlamellar setae longer than rostral and lamellar setae; all setiform, ciliate unilaterally. Sensilli setiform, with four to five long branches. Notogastral setae long, ciliate unilaterally. Epimeral region with muscle sigilla. Anogenital setae smooth (except ciliate adanal setae). Lyrifissures iad located in inverse apoanal or paraanal position. Description Measurements: Body length 647 (holotype), 647680 (mean 660; 11 paratypes); notogaster width 348 (holotype), 332-356 (mean 346; 11 paratypes). Integument (Figs 1-3): Body colour brown to yellow-brownish. Dorsal surface of prodorsum smooth; lateral sides with small microgranulate parts between bothridia and acetabula I, II. Interbothridial region with two pairs of distinct muscle sigilla. Surface of notogaster and anogenital region smooth or rarely foveolate (diameter foveolae up to 4 µm). Distance between foveolae considerable longer than diameter of foveolae. Epimeral region with numerous muscle sigilla. Prodorsum (Figs 1, 3-8): Rostrum rounded. Lamellar lines thin, not visible absolutely in many specimens. Triangular tubercle located posteriorly to each bothridium and interlamellar seta. Rostral (ro, 45-53), lamellar (le, 53-61), interlamellar (in, 90-102) and exobothridial (ex, 24-36) setae setiform, with short cilia unilaterally. Sensilli (ss, 127-143) setiform, having four (rarely five) long branches in medio-distal part. Notogaster (Fig. 1): Anterior border convex. A pair of setae c is absent (only alveoli present). Twelve other pairs of notogastral setae long (123-151), setiform, with short cilia unilaterally. Setae in anterior half of body slightly shorter than in posterior half. Lyrifissures ia, im, ip, ih and ips distinct, located typically for genus. Opisthonotal gland openings (gla) located posteriorly to setae h3. Gnathosoma (Figs 9-12): Subcapitulum longer than wide (155-168 × 98-110). Subcapitular setae (a, m, h) setiform, smooth, similar in length (20-28). Two pairs of adoral setae (or1, or2, 4-6) present, thornlike. Palps (82-94) with setation 0-2-1-3-9(+ω). Setae of femora with long, thickened cilia; setae of genua and tibia with short cilia unilaterally; setae of tarsi smooth. Solenidion long, thickened, blunt-ended, pressed to the palptarsus surface, attached with distal seta u" in distal half. Chelicerae (159-168) chelate-dentate. Cheliceral setae setiform, barbed; cha (36-45) longer than chb (24-28). Trägårdh’s organ (Tg) distinct. Epimeral and lateral podosomal regions (Figs 2, 3, 13, 14): Epimeral border IV convex posteriorly. Epimeral setae setiform; 1c, 3c and 4c with short cilia unilaterally, others smooth. Setae 3c, 4a and 4c (53-57) longer than 1b, 1c, 3b (32-41) and 1a, 2a, 3a, 4b (16-20). Pedotecta I (Pd I) convex. Discidia (dis) triangular, blunt-ended. 3 Anogenital region (Figs 2, 15, 16): Five pairs of genital (g1 -g5, 16-20), one pair of aggenital (ag, 16-20) and two pairs of anal (an1, 36-49; an2, 28-32) setiform, smooth. Three pairs of adanal setae (ad1, 98-118; ad2, 77-90; ad3, 49-57) setiform, with short cilia unilaterally. Lyrifissures iad located in inverse apoanal (paraanal in two specimens; left lyrifissure inverse apoanal, right lirifissure paraanal in one specimen) position. Legs (Figs 17-19): Generally, similar to Gittella ecuadoriensis Ermilov & Kalúz, 2012. Formulae of leg setation and solenidia: I (1-5-2-4-20) [1-2-2], II (1-5-2-4-16) [1-1-2], III (2-3-1-3-15) [1-1-0], IV (1-2-2-3-12) [0-1-0]; homology of setae and solenidia indicated in Table 1. Setae p on tarsi I setiform; on tarsi II-IV thorn-like. Setae tc' on leg II, tc" on leg III, a" on leg IV with thickened cilia bilaterally. Setae a', s, pv' on leg II, a", s, pv" on leg III, pv" on leg IV with thickened cilia unilaterally. Famulus (e) setiform, straight or bent, blunt-ended. Solenidia ω1, ω2 on tarsi I, II, φ2 on tibiae I, φ on tibiae II, σ on tibiae III thickened, blunt-ended. Other solenidia thinner and longer, weakly blunt distally. Etymology. The specific name variabilis refers to the variability of some morphological characters (body surface, orientation of lyrifissures iad). Remarks. In having the combination of morphological characters (setiform, branched sensilli; long and ciliate notogastral setae; length of adanal setae; presence of two pairs of interbothridial muscle sigilla), Gittella variabilis spec. nov. is most similar to Gittella maxima (Balogh & Mahunka, 1981) (see Balogh & Mahunka 1981), however, it differs from the latter p1 1 ad 1 an 1 ad 2 an 2 ad 3 g 5 ag 4a 3a 2a 3b 3c 1c 1b 1a 4b 4c di s iad h 1 ro h 2 gla im lm lp la ia ia in in c c le ro le ex ss ss Pd I Pd I Pd I da dm h 3 dp p 2 p 3 12 3 Figs 1-3. Gittella variabilis spec. nov. 1. Dorsal view. 2. Ventral view (legs, subcapitular setae and palps not shown). 3. Lateral view of prodorsum (legs and gnathosoma not shown). Scale bars: 1, 2 = 200 µm; 3 = 100 µm. 4 by the morphology of sensilli (with long four to five branches in the new species versus with four long and four short branches in G. maxima), presence of muscle sigilla in epimeral region (versus absent in G. maxima), morphology of notogastral setae (ciliate unilaterally in the new species versus ciliate not unilaterally in G. maxima). 4 5 6 7 9 10 12 11 8 in le ro u" ω ss ex m h cha chb Tg or 2 or 1 a Figs 4-12. Gittella variabilis spec. nov. 4. Rostral seta. 5. Lamellar seta. 6. Interlamellar seta. 7. Sensillus. 8. Exobothridial seta. 9. Subcapitulum, left half. 10. Adoral setae. 11. Palp. 12. Chelicera, anterior part. Scale bars: 4, 5, 8, 10, 11 = 10 µm; 6, 7, 12 = 20 µm; 9 = 50 µm. 5 Gittella minor spec. nov. Figs 20-34 Material examined. Holotype: male, Southern Ecuador, 3°58' S 79°50' W, Estación Científica San Francisco, 2000 m a.s.l., upper organic soil layer in mostly undisturbed rain forest, 01.04.2008 (ZISP). – Paratypes: one male and two females in SZMN, and three males in PC, same locality and date as holotype. Diagnosis. Body size 311-328 × 147-159. Body surface smooth. Lamellar lines distinct. Interbothridial region with two pairs of muscle sigilla. Lamellar setae longer than rostral and interlamellar setae. Sensilli with dilated head, having six long branches. Notogastral setae of medium size, ciliate. Epimeral region with muscle sigilla. Anogenital setae smooth (except ciliate adanal setae). Lyrifissures iad located in inverse apoanal position. 13 14 15 16 17 18 19 4a 4c g 1 g 2 g 3 an 2 an 1 g 5 g 4 tc' p' u' tc' pv' tc" p" u" Figs 13-19. Gittella variabilis spec. nov. 13. Epimeral seta 4a. 14. Epimeral seta 4c. 15. Genital plate, right. 16. Anal plate, right. 17. Leg tarsus I, right, antiaxial view, anterior part. 18. Seta tc' on leg tarsus II. 19. Seta pv' on leg tarsus II. Scale bars: 13, 14, 17-19 = 10 µm; 15, 16 = 20 µm. 6 Description Measurements: Body length 311 (holotype), 311-328 (mean 317; six paratypes); notogaster width 147 (holotype), 147-159 (mean 155; six paratypes). Integument (Figs 20-22): Body colour yellowbrownish. Body surface smooth; lateral sides with small microgranulate parts between bothridia and acetabula I, II. Interbothridial region with two pairs of distinct muscle sigilla. Epimeral region with numerous muscle sigilla. Prodorsum (Figs 20, 22-27): Rostrum rounded. Lamellar lines well developed. Triangular tubercle located posteriorly to each bothridium and interlamellar seta. Rostral (16-20), lamellar (24-32), interlamellar (16-20) and exobothridial (8-12) setae setiform, with very short cilia unilaterally. Sensilli (61-69) with dilated head, having six long branches. Notogaster (Figs 20, 28): Anterior border convex. A pair of setae c is absent (only alveoli present). Twelve other pairs of notogastral setae long (36-45), setiform, with short cilia unilaterally. Lyrifissures ia, im, ip, ih and ips distinct, located typically for genus. Opisthonotal gland openings located posteriorly to setae h3. Gnathosoma: Subcapitulum longer than wide (82-90 × 49-53). Subcapitular setae (a, m, h) setiform, smooth, similar in length (16-20). Two pairs of adoral setae present, thorn-like (4). Palps (49-53) with setation 0-2-1-3-9(+ω). Setae of femora with long, thickFigs 20-22. Gittella minor spec. nov. 20. Dorsal view. 21. Ventral view (legs, subcapitular setae and palps not shown). 22. Lateral view of prodorsum (legs and gnathosoma not shown). Scale bar: 1, 2 = 100 µm; 3 = 50 µm. p1 1 ad 1 an 1 ad 2 an 2 ad 3 g 5 ag 4a 3a 2a 3b 3c 1c 1b 1a 4b 4c dis iad h 1 h 2 gla im lm lp la ia ia in in c c le ro le ex ss ss ro Pd I Pd I Pd I da dm h 3 dp p 2 p 3 20 21 22 7 Figs 23-34. Gittella minor spec. nov. 23. Rostral seta. 24. Lamellar seta. 25. Interlamellar seta. 26. Sensillus. 27. Exobothridial seta. 28. Notogastral seta lm. 29. Epimeral seta 3a. 30. Epimeral seta 3b. 31. Epimeral seta 3c. 32. Genital plate, left. 33. Anal plate, left. 34. Adanal seta ad2. Scale bars: 23-32, 34 = 10 µm; 33 = 20 µm. 23 24 25 27 29 31 28 30 26 34 33 32 ss ex lm 3a 3c 3b in le ro ad 2 an 2 an 1 g 1 g 2 g 3 g 5 g 4 ened cilia; setae of genua and tibia with short cilia unilaterally; setae of tarsi smooth. Solenidion long, thickened, blunt-ended, pressed to the palptarsus surface, attached with distal seta u" in distal half. Chelicerae (82-90) chelate-dentate. Cheliceral setae setiform, barbed; cha (24-28) longer than chb (16). Trägårdh’s organ distinct. Epimeral and lateral podosomal regions (Figs 21, 22, 29-31): Epimeral border IV convex posteriorly. Epimeral setae setiform; 1c, 3c and 4c with short cilia unilaterally, others smooth. Setae 1b, 1c, 3b, 3c, 3c, 4a and 4c (16-20) longer than others (6-12). Pedotecta I convex. Discidia triangular, blunt-ended. Anogenital region (Figs 21, 32-34): Five pairs of genital (4-6), one pair of aggenital (4-6) and two pairs of anal (an1, 8-12; an2, 4-8) setiform, smooth. Three pairs of adanal setae (ad1, ad2, 24-32; ad3, 12-16) setiform, with short cilia unilaterally. Lyrifissures iad located in inverse apoanal position. Legs: Similar to Gittella variabilis spec. nov. Homology of setae and solenidia indicated in Table 1. Etymology. The specific name minor refers to the small body size. Remarks. In having the combination of morphological characters (smooth body surface; sensilli with dilated head, having branches; ciliate notogastral setae of medium length), Gittella minor spec. nov. is most similar to Gittella insularis Mahunka, 1998 (see Mahunka 1998), however, it differs from the latter by the smaller body size (311-328 × 147-159 in the new species versus 576-642 × 255-297 in G. insularis), presence of two pairs of interbothridial muscle sigilla (versus three pairs in G. insularis), ciliate rostral and interlamellar setae (versus smooth in G. insularis). 8 Acknowledgements We cordially thank anonymous reviewers for the valuable comments. Oribatid mites were investigated as part of the Research Unit “Biodiversity and sustainable management of a megadiverse mountain ecosystem in South Ecuador”, subproject “Soil fauna: Diversity and functioning” headed by Mark Maraun and Stefan Scheu; financial support by the German Research Foundation is gratefully acknowledged (RU 816). References Balogh, J. & Balogh, P. 1992. The oribatid mites genera of the world, Vol. 1. 263 pp., Budapest (Hungarian National Museum Press). – – & Mahunka, S. 1981. New data to the knowledge of the oribatid fauna of the Neogaea, VI. (Acari). Acta Zoologica Academiae Scientiarum Hungaricae 27 (1-2): 49-102. Ermilov, S. G. & Kalúz, S. 2012. Two new species of Oppiidae (Acari: Oribatida) from Ecuador. International Journal of Acarology 38 (6): 521-527. Hammer, M. 1961. Investigations on the oribatid fauna of the Andes Mountains. II. Peru. Det Kongelige Danske Videnskabernes Selskab Biologiske Skrifter 13 (1): 1-157. Mahunka, S. 1998. New data on oribatids (Acari: Oribatida) from St. Lucia (Antilles) (Acarologica Genavensia LXXXIX). Revue Suisse de Zoologie 105 (4): 839-877. Norton, R. A. & Behan-Pelletier, V. M. 2009. Oribatida, Chapter 15. Pp. 430-564 in: Krantz, G. W. & Walter, D. E. (eds). A manual of acarology. Lubbock, TX (Texas Tech University Press). Subías, L. S. & Balogh, P. 1989. Identification keys to the genera of Oppiidae Grandjean, 1951 (Acari: Oribatei). Acta Zoologica Hungarica 35 (3-4): 355-412.