SPIXIANA 1 43-87 München, 01. März 1996 ISSN 0341-8391 Chironomidae from Ethiopia, Part 3. Chironomini, with description of a new species (Insecta, Diptera) By A. D. Harrison Harrison, A. D. (1996): Chironomidae from Ethiopia, Part 3. Chironomini, with description of a new species (Insecta, Diptera). - Spixiana 19/1: 43-87 Males, females, pupae and larvae of Chironomini found in the Ethiopian Highlands and Rift Valley are described. Not all stages were available for all species. One new species is described: Polypedilum (Polypedilum) tesfayi, spec. nov. Dr. A. D. Harrison, 111A Berg Rd., Fish Hoek, 7975, South Africa. Introduction This paper is the third in the series on Chironomidae collected in Ethiopia; the two previous papers were onthe Tanypodinae (Harrison 1991), and the Orthocladiinae (Harrison 1992). Freeman & Cranston (1980) list Chironomini of Sub-Saharan Africa; most of the males of these are illustrated by Freeman (1957, 1958) and by Lehmann (1979, 1981), who also describes some females, larvae and pupae. In this paper detailed descriptions are given of males of known species, and also of females, pupae and larvae when available. One new species is described. Dicrotendipes septemmaculatus and D. pilosimanus were also collected but are not dealt with here; they are given special treatment in Harrison (1993). Specimens were collected by the author and colleagues from the Biology Department, Addis Abba University. The ecological background is given in Harrison & Hynes (1988), Tudorancea & Harrison (1988), Tilahun Kibret & Harrison (1989), Tudorancea, Baxter & Fernando (1989) and Tesfaye Berhe, Harrison & Hynes (1989). Methods Adults were collected by sweeping with a net in marginal vegetation along river banks and lake- shores; many were caught at lights. Running water species were bred out in an aquarium in the laboratory at Addis Ababa. Larvae and pupae were collected during lake and river survey pro- grammes. Specimens were mounted in Canada balsam dissolved in cellosolve; measurements were made with an eyepiece micrometer, and all drawings with a drawing tube on the microscope. Generic definitions of males follow the model of Cranston, Dillon, Pinder & Reiss (1989), of females the model of Saether (1977), of pupae the model of Pinder & Reiss (1986) and of larvae the model of Pinder & Reiss (1983). Langton (1984) was also used for the pupal studies. Morphological terminolgy is from Saether (1980). Station numbers (ET) given for river sites in the text are those of Harrison & Hynes (1989) who give descriptions and map references. Thetype and paratype of the new species are deposited in the Zoologische Staatssammlung, Munich, Germany. Most of the other specimens have been deposited in the same museum. 43 Chironomus alluaudi Kieffer Chironomus alluaudi, Freeman 1957 All three stages of the Ethiopian material were associated by breeding out material in Addis Ababa. Freeman separated alluaudi from other similar species by means of the large dark spots on abdominal segments 1-5 and the anal point that appears almost straight in side view. Adult male (N =2 mounted and many unmounted). Freeman9s description is augmented as follows: Wing length 4.0-6.0 mm. Head. AR 3.0-3.1. Frontal tubercles about as long as wide. Palp segments: 130, 130, 221, 260, 364 um, 4 subapical sensilla on segment 3. Thorax. Scutal tubercle present. Setation: Lateral antepronotals 4, dorsocentrals about 20 biserial, posterior prealars 9 uniserial, scutellars 6 per side. Wing. Setation: R 20, R, 14, R,,; nil. Leg. LR fore 1.95, mid 1.8, hind 1.4-1.5. Sensilla chaetica on tarsomere 1: midleg 10, hindleg 11. Tarsomeres 2 & 3 of foreleg with beard. Abdomen. Large brown spots on tergites 1-5. Hypopygium. As described by Freeman, and with strong tergite bands, not meeting anterior to the 10 median tergite setae. About 18 anal tergite setae per side. Dorsal edge of anal point almost straight in lateral view. Base of superior volsella small with setae and sparse small microtrichia (Fig. 1); digitiform apex broadest in middle. Inferior volsella with about 36 strong, curved setae. Adult female (N = 2 mounted). Wing length 5.6 mm. Head. AR 0.4. Apical flagellomere 0.9x length of 3 and 4 together. Frontal tubercles twice as long as wide. Thorax. Scutal tubercle present. Setation: Lateral antepronotals 4, dorsocentrals about 20 biserial, posterior prealars 6 uniserial, scutellars 7 per side. Wing. Setation: R 22, R, 35, R,,; 36. Leg. LR fore 0.8, mid 0.5, hind 0.65. Sensilla chaetica on tarsomere 1: mid about 125, hind about 115. Abdomen. Large brown spots on tergites 1-5. Genitalia (Figs 2-4). Chitinized setigerous ventral ridge on tergite VIII anterior to dorsomesal lobe of gonocoxite VIII. Gonocoxapodeme VII rounded caudally and not joined mesally. Gonopophysis VII divided into a large, tongue-shaped dorsomesal lobe and brushlike ventrolateral lobe; apodeme lobe small with microtrichia. Coxosternapodeme large, dark and curved anteriorly (Fig. 3, left). Gonocoxite IX with about 15 setae. X with about 12 setae per side. Postgenital plate (not in figure) well- developed and rounded at apex. Labia without microtrichia. Seminal capsules oval, 143 um long, spermathecal ducts with common opening. Pupa (N = 2 mounted). Cephalothorax. Granulose with small scutal tubercles, 2 very small pre- corneals, 2 very small antepronotals, 4 inconspicuous dorsocentrals in pairs close together. Abdomen. Tergite I without shagreen, II-Vllargely covered with shagreen of fairly uniform appear- ance, anterior points about 6 nm, central points 15-19 um and posterior points 24-31 um; VII with 2 anterior patches of small points; VIII with 2 posterior patches of small points; conjunctives IV/V, V/VI and VI/VII with very fine shagreen. Hook row on II 0.73-0.85 width of tergite. Pedes spuri B on segment II and small pedes spurii A on IV. Posterolateral spur of VIII broad and somewhat curved (Fig. 5). Segment I without L setae, II-IV each with 3, V-VII with 4 lamelliform L setae. VII with 5 lamelliform L setae. Anal lobe with fringe of about 105 setae. Larva (N = 7 mounted). Head capsule length about 845 y1m. Antenna. Similar to generic definition. Labrum. Similar to definition; S I plumose on both sides with lateral feathering extending about the distal one third. Pecten epipharynx (Fig. 6) with 12 teeth of irregular length. Premandible with 2 teeth. Mandible (Fig. 7). Dorsal tooth pale, the rest dark, seta subdentalis simple and pointed, radially arranged grooves on outer surface. Mentum (Fig. 8). In all specimens teeth were worn and rounded but arrangement is typical for genus. Ventrolateral plates are 0.95x width of mentum and separated by about one third width of mentum. Maxilla (Fig. 9). Similar in general appearance to that illustrated by Cranston & Rice (1983) for the 44 Figs 1-9. Chironomus alluaudi. Adult: 1. Superior volsella. 2. ? genitalia, ventral. 3. ? genitalia, ventral. 4. ? gen- italia, lateral. Pupa: 5. Abdomen, posterolateral spur. Larva: 6. Labrum, pecten epipharynx. 7. Mandible. 8. Mentum. 9. Maxilla. Figs 10-12. Chironomus caliptertus. Adult: 10 ® genitalia, ventral. 11. ? Dorsomesal and apodeme lobes. 12. ? gen- italia, lateral. Orthocladiinae. Chaetulae of palpiger about one third the length of palp, a-seta of palp long and thin, b-seta and bisensillum absent, seta maxillaris 1+2, no pecten galearis, sensilla basiconicum thin and pointed, multilabate sensillum with broad lobes, lacinal chaetae near tip broadly rounded, one at least 2x length of others, one narrow and finely pectinate. Paraxial seta small, antaxial seta with base more than one third length of seta, ring organ on raised base, appendix seta simple. Body. Similar to definition, lateral tubules and 2 pairs of ventral tubules, anal tubules short and rounded. Specimens examined. Adults: Numerous dd and ? 9, at lights, Addis Ababa, October & November 1982; numer- ous dd and 29 bred from larvae collected in polluted Kebena River below ET.2C, Addis Ababa, March & April 1985; 18, Kosso River, ET.17,84/1/12;1d, pond near Dinsho, Bale Mountains, 84/10/20. Pupae: Two, Kebena River below ET2C, Addis Ababa 1985. Larvae: Numerous, polluted Kebena River, below ET.2C, Addis Ababa 1985. Ecology. Common to abundant in the polluted Kebena River flowing through Addis Ababa (Tesfaye Berhe et al. 1989), not found in unpolluted rivers or lakes in Ethiopian Highlands. Normal habitat appears to be ponds or small standing water. Distribution. Kenya (Freeman 1957) and Ethiopian Highlands. Chironomus calipterus Kieffer . Chironomus calipterus, Freeman 1957; Dejoux 1970b; Cranston & Judd 1989. Dejoux associated all three stages and described the pupa and larva in detail. Freeman, and Cranston & Judd illustrate the male wing and the hypopygium. Adult male (N = 2 mounted). Previous descriptions are augmented as follows: Wing length 3 mm. Head. AR 2.8. Frontal tubercles about 3x as long as broad. Palp segments: 37, 37, 155, 155, 233 pm. 3 subapical sensilla on segment 3. Thorax. Small scutal tubercle present. Setation: Lateral antepronotals 5, dorsocentrals 17 partly biserial, posterior prealars 4, scutellars 7 per side. Wing. With clouds as illustrated by Freeman, spots over cross vein and in cells (Cranston & Judd), visible in mounts, result from refraction by microtrichia. Setation: R 38, R, 25, R,,, 32, squama 21. Leg. LR fore 1.7, mid 0.6, hind 0.7. Sensilla chaetica on tarsomere 1: midleg 7, hindleg 8. No beard on foreleg. Hypopygium. As described by Freeman, Dejoux, and Cranston & Judd. Base of superior volsella small, with setae and long microtrichia up to base of curved digitiform appendix. Inferior volsella with about 15 strong curved setae. Adult female (N = 4 mounted). Wing length 3 mm. Head. AR 0.3-0.4. Frontal tubercles about 3x as long as broad. Palp segments: 47, 43, 146, 167, 267 j1m. Thorax. Small scutal tubercle. Setation: Lateral antepronotals 4, dorsocentrals 30 partly biserial, posterior prealars 4, scutellars 6 per side. Wing. Similar to male. Setation: R 42, R, 34, R,,,53, squama 9. Leg. LR fore 1.7-1.8, mid 0.5, hind 0.7. Sensilla chaetica on tarsomere 1: mid 46, hind 56. Genitalia (Figs 10-12). Chitinized ventral ridge of VIII weak, well anterior to dorsomesal lobe of gonopophysis. Dorsomesal lobe large, microtrichia not extending to edge (Fig. 11, right). Ventrolateral lobe (Fig. 11, right) with short microtrichia. Apodeme lobe (Fig. 11, left) with weakly chitinized base and with microtrichia. Gonocoxapodemes broad and do not join. Coxosternapodeme dark, curved. Gonocoxite IX reduced to small, chitinized ridge with no setae (Fig. 12). Segment X with 8 setae per side. Post genital plate (Fig. 10) pointed. Labia without microtrichia. Seminal capsules almost oval, 109 um long, ducts with common opening. Pupa. None found. Dejoux9s illustrations show a pupa rather typical for the genus with dorsocentrals easily visible. There are no posterolateral patches of spines on any of the tergites and the posterolateral spur of VII is fairly broad, dark and bent with about 4 points. Larva. None found. Dejoux9s illustrations show a larva fairly typical for the genus. Premandible has 2 teeth and brush. Pecten epipharynx has 22 irregular teeth. Mentum has typical trifid central tooth. Anal tubercles short. 46 Specimens examined. Numerous dd and 2? at lights, Lake Awasa, 81/4/15. Comments. This species superficially resembles C. formosipennis because of the marked wings, but does not share its peculiarities, such as the shape of the male superior volsella, sensilla chaetica on female tarsomeres 2 and 3, and the simple central tooth of the larval mentum. In these and other respects it is more typical of the genus. Ecology. Though adults were found on one occasion at lights at Lake Awasa no larvae or pupae were found during the extensive sampling of the lake (Tilahun Kibret & Harrison 1989). The larvae must have been living in shallow pools or swampy regions not part of the main lake. Distribution. Afrotropical region, circum-Mediterranean and Arabian Peninsula. Chironomus formosipennis Kieffer Chironomus formosipennis, Freeman 1957; Dejoux 1970b. Dejoux (1970b) associated all three stages and his association was confirmed by the Ethiopian material. Freeman (1957) and Dejoux describe the hypopygium, and Dejoux describes the pupa and larva in detail. Adult male (N = 2 mounted). Freeman9s description is augmented as follows: Wing length 4.3-4.4 mm. Head. AR 3.7. Frontal tubercles on a short stalk, about 2x as long as broad. Palp segments: 62, 78, 202, 186, 280 um, 4 subapical sensilla on segment 3. Thorax. Scutal tubercle present. Setation: Lateral antepronotals nil, dorsocentrals about 40 bi- or triserial, posterior prealars 8 uniserial, scutellars about 20 per side biserial. Wing. With clouds as illustrated by Freeman; spot over cross vein and spots in cells are also visible in mounts and result from refraction by microtrichia. Setation: R 52, R, 35, R,,, 44, squama 18. Leg. LR fore 1.3, mid 0.5, hind 0.7. Sensilla chaetica on tarsomere 1: midleg 15, hindleg 10. Tarsomer- es 1 & 2 of foreleg with beard. Hypopygium. As described by Freeman and Dejoux, with base of superior volsella larger than usual for the genus (Fig. 13), ventral part with small setae almost obscured by dense long microtrichia, and digitiform apex broad and curved. Inferior volsella with about 45 strong curved setae. In addition, tergal bands meet anterior to, and demarcate, the anterior edge of oval area with median anal tergite setae. Adult female (N = 3 mounted). Wing length 4.8 mm. Head. AR 0.5. Frontal tubercles about 2x as long as wide, on short stalk. Palp segments: 78, 91, 169, 208, 273 am. Four subapical sensilla on segment 3. Thorax. Scutal tubercle present. Setation: Lateral antepronotals nil, dorsocentrals about 36 bi- and triserial, posterior prealars 7 uniserial, scutellars about 30 per side biserial. Wing. Setation R 42, R, 30, R,.; 54. Leg. LR fore missing on all specimens, mid 0.58, hind 0.68. Sensilla chaetica: On tarsomere 1: midleg 64, hindleg 84; On tarsomere 2: midleg 18, hindleg 21; On tarsomere 3: midleg 9, hindleg 11. Genitalia (Figs 14-16). Strongly chitinized setigerous ventral ridge of VIII opposite dorsomesal lobe of gonopophysis (Fig. 15), posteroventral edge of tergite VIII partly covering setigerous portion of segment X. Dorsomesal lobe of gonopophysis VIII large, microtrichia not extending to edge. Ventro- lateral lobe (Fig. 15, right) narrow with small microtrichia. Apodeme lobe (Fig. 15, left) with base strongly chitinized, with long microtrichia. Gonocoxapodeme narrow and not joined. Coxosternapo- deme almost black, curved. Gonocoxite IX small, visible in lateral view only (Fig. 16), three setae. Segment X with about 15 setae per side. Postgenital plate (Fig. 14) pointed. Labia without microtrichia. Seminal capsules almost spherical, 133 am diameter, spermathecal ducts with common opening. Pupa (N = 4 mounted). As described by Dejoux, and as follows: Cephalothorax. Granulose with small scutal tubercles. Three very small precorneals, 2 minute antepronotals, 4 dorsocentrals, one of each pair large and dark, the other very small. Abdomen. Shagreen on tergites, as for genus. Length of spines: anterior about 6 m grading to posterior 37 um; hook row almost full width of tergite II; pedes spuri B on II, and A on sternite IV with 47 large transparent hooks. Postero-lateral patches of spines on tergites V-VII. Conjunctives IV/V and V/VI with fine shagreen. Posterolateral spur of VIII broad and dark with 4 points. Segment I with1L seta, IH and III with 3 and IV with 4, V-VII with 4 lamelliform L setae and VIII with 5. Anal lobe with frings of about 110 setae. Larva (N = 3 mounted). As described by Dejoux and as follows: Head capsule length 845-900 pm. Antenna. Typical for genus. Labrum. S Iappears pectinate with about 20 teeth on one side only, other S setae as for genus. Pecten epipharynx with about 16 teeth, premandible with 3 teeth and brush. Mandible. Dorsal tooth pale, 3 other teeth dark, seta subdentalis simple, radially arranged grooves basally on outer surface. Mentum. Central tooth simple, the two smaller outer toothlets which make the central tooth of other species appear trifid are here attached to the first lateral teeth, making each of them appear trifid. Maxilla. Similar to C. alluaudi. Body, Similar to generic definition, with lateral tubules and 2 pairs of ventral tubules; anal tubules as long as, or longer than the prolegs. Specimens examined. Adults: Numerous dd and 9%, at lights, Lake Ziway, 82/12/31. Larvae and pupae: One with pharate d, Bulbulla Shet, ET.34, flowing out of L. Ziway, 84/2/24. Comments. This species has a number of distinctive features. The superior volsella of the male resembles that of the subgenus Lobochironomus (Cranston et al.). The female has sensilla chaetica on tarsomeres 2 and 3 in addition to those on tarsomere 1, on mid and hind legs; and gonocoxite IX is very small. The pupa has posterolateral patches of spines on tergites V-VII. The larva has a pectinateSI with teeth on one side only, and a mentum with a simple central tooth and trifid first lateral teeth. It is premature to allocate this species to any subgenus until much more is known about all life stages of the genus. Ecology. Larvae were not found in Lake Ziway (Tudorancea et al. 1989), but in the slow-flowing Bulbulla Shet. Those adults captured at lights appeared to come from a shallow pool behind the reed beds of the lake, not the main lake. Dejoux found them in L. Chad (Dejoux 1970b, 1983). Distribution. Most of Africa south of the Sahara. Chironomus imicola Kieffer Chironomus imicola, Freeman 1957; Freeman & Cranston 1980. Freeman describes the male and its hypopygium and gives a short description of the female. Further details of the male and female are given here. Unfortunately the pupa and larva were not found. Adult male (N = 2 mounted). Close to generic definition except for details given here. Wing length 4.8 mm. Head. AR 3.4. Frontal tubercles nearly 3x as long as broad. Palp segments: 91, 78, 260, 260, 403 um. 7 subapical sensilla on segment 3. Thorax. Small scutal tubercle present. Setation: Lateral antepronotals 5, dorsocentrals 31 biserial, posterior prealars 8, scutellars 10 per side partly biserial. Wing. Setation: Brachiolum 3, R 53, R, 35, R,,, 45, squama 57 bi- or multiserial. Leg. LR fore 1.7. mid 0.6-0.7, hind 0.6-0.8. Sensilla chaetica on tarsomere 1: midleg 5-8, hind leg 5-13. No beard on foreleg. Hypopygium (Fig. 17). Strong anal tergite bands (not in figure) meeting to delineate anterior margin ofroughly oval area with about 15 median anal tergite setae. About 12 apical anal setae per side. Anal point strongly down turned. Superior volsella broad, strongly setose, digitform apex arising dorsome- dialy. Inferior volsella with about 30 strong, curved setae. Adult female (N = 1 mounted). Wing length 4.8 mm. Head. AR 0.4. Frontal tubercles as for male. Palp segments: 65, 91, 273, 286, 442 n1m. 7 subterminal sensory setae on segment 3. 48 N Na u U i & y a EIN I IN N A N ST Figs 13-16. Chironomus formosipennis. Adult: 13. Superior volsella. 14. ? genitalia, ventral. 15. Apodemaend ven- trolateral lobes. 16. ? genitalia, lateral. Figs 17-19. Chironomus imicola. Adult: 17. Hypopygium. 18. $ genitalia, ventral. 19. ? genitalia, apodeme and ventrolateral lobes. Figs 20-25. Harnischia curtilamellAadtulat. d : 20. Tentorium, 21. Hypopygium, 22. Anal point, lateral. 23. Superi- or volsella. Adult 2: 24. Genitalia, ventral. 25. Seminal vesicles, ducts. 49 Thorax. Small scutal tubercle. Setation: Lateral antepronotals 5, dorsocentrals about 30, posterior prealars 5, scutellum broken. Wing. Setation: Brachiolum 5, R 57, R, 53, R,., 90, squama about 56 bi- or multiserial. Leg. LR fore missing, mid 0.6, hind 0.7. Sensilla chaetica on tarsomere 1: mid 76, hind 102. Genitalia (Figs 18, 19). Chitinized ventral ridge of VIII weak with one seta. Dorsomesal lobe of gonopophysis VIII large, microtrichia not extending to edge. Ventrolateral lobe (Fig. 19, right) with long microtrichia. Apodeme lobe (Fig. 19, left) relatively large with well chitinized base and long microtrichia. Gonocoxapodeme narrow but broad towards ventral mid line, not joined (Fig. 18). Coxosternapodeme narrow and curved. Gonocoxite IX well developed with 4 setae. Segment X with about 10 setae per side, post genital plate pointed. Labia without microtrichia. Seminal capsules ovoid with short neck, 155 um long, ducts almost straight with common opening. Specimens examined. 2S3d netted near Lake Awasa, 84/2/11; 18,1% netted near L. Awasa, 84/8/ 25. Comments. Freeman considered this species to be similar to the Palaearctic species C. paganus Meigen because of the structure of the superior volsella. This species is used for the diagnosis of the genus Einfeldia by Cranston et al. (1989). Nevertheless, imicola only resembles their concept of Einfeldia in the structure of the superior volsella. It differs in that the scutum has a tubercle, the squama has a large number of setae, and the anal bands are strong, joining anteriorly to the anal tergite setae. The female genitalia are very similar to those of the other species of Chironomus described here, except formosipennis and those of plumosus (L) (Sae- ther 1977), but differ markedly from those of E. pagana in that the gonocoxapodemes of VIII are not joined mesally anterior to the vagina (Saether 1977). C. imicola may belong to the subgenus Lobochironomus, but this placement must wait until this subgenus has been defined for the female and immatures, and the immatures of imicola have been described. Ecology. Although adults were netted near the shore of Lake Awasa no larvae were found during an extensive survey (Tilahun Kibret & Harrison 1989). The larvae must have been developing in the swampy area near the lake. Distribution. Most of Afrotropical region as far south as the Transvaal, also Madagascar (ZSM unpub!.). Chironomus transvaalensis Kieffer Chironomus transvaalensis, Freeman 1957. Only one male was collected. Adult male (N = 1 mounted). The male has been described well by Freeman and is not-detailed again here. The larva and pupa are described by McLachlan (1969). Specimen examined. 1d, at lights, Lake Ziway, 82/12/31. Distribution. Afrotropical region, Israel (Laville & Reiss 1993). Cryptochironomus diceras Kieffer Chironomus (Cryptochironomus) diceras, Freeman 1957. Cryptochironomus diceras, McLachlan 1969; Freeman & Cranston 1980; Cranston & Judd 1989. The male adult only is described. Adult male (N = 1 mounted). Freeman9s description is supplemented as follows: Wing length 2.2 mm. Head. AR 2.3. Frontal tubercles absent. Palp segments: 37, 47, 133, 115, 171 um. Two subapical sensilla on segment 3. Thorax. Scutal tubercle absent. Setation: Lateral antepronotals 4, dorsocentrals 12 uniserial, poste- rior prealars 4, scutellars98 per side biserial. 50 Wing. Setation: Brachiolum 2, R 14, R, 8, R,,, 16, squama 4. Leg. LR fore 1.7, mid 0.6, hind 0.7. Sensilla chaetica on tarsomere 1: mid 11, hind 5. Hypopygium (Fig. 26). Strong anal tergite bands joining well anterior to anal point and extending to point as abroad ridge; anal point fairly broad with dorsal ridge extending forwards a short distance onto the anal tergite. Superior volsella small, bent with 2 setae. Inferior volsella very small with two setae (Fig. 26, right). Gonostylus fused with gonocoxite. Adult female. Freeman (1957) gives a short description but does not illustrate the genitalia. Pupa. McLachlan (1969) states that the pupa is similar to those of C. lindneri and C. neonilicola. Larva. McLachlan shows that the larva differs from that of lindneriin that it has a fine seta subdentalis on the mandible and the 4th tooth on the mentum is much taller than the inner teeth. Specimens examined. Adults: 13 caught at lights, Lake Langano, 83/3/14; 338 at lights, L. Langano, 83/12/11. Comments. The superior volsella does not cover the inferior in all specimens and lies well dorsal to it Ecology. Although all the adults were caught on the shores of Lake Langano no larvae that could belong to this species were caught in the lake, or in the outflow stream of the lake or in any of the lakes nearby. Distribution. Over most of sub-Saharan Africa and in the Arabian Peninsula (Cranston & Judd 1989). Cryptochironomus lindneri (Freeman) Chironomus (Cryptochironomus) lindneri Freeman, 1957. Cryptochironomus lindneri, McLachlan 1969; Freeman & Cranston 1980. The male adult, the pupa and the larva were associated by means of a male pupa with larval head capsule attached. No adult female was found but some information is available from a female pupa. Adult male (N = 3 mounted). Freeman9s description is augmented as follows: Wing length 3.4 mm. Head. AR 3.0. Frontal tubercles present. Palp segments: 86, 81, 152, 136, 236 um. No subapical sensilla on segment 3. Thorax. Scutum not projecting over antepronotum; very small scutal tubercle present. Setation: Lateral antepronotals 4, dorsocentrals 18 irregularly biserial, posterior prealars 6, scutellars 6 per side biserial. Wing. Setation: Brachiolum nil, R 21, R, nil, R,,, 6 towards tip, squama 24. Leg. LR fore 1.4, mid 0.5, hind 0.4. Sensilla chaetica on tarsomere 1: mid 3-7, hind 4-5; one male had one sensilla on tarsomere 2 of one midleg. Slight beard on tarsomeres 1 and 2 of foreleg. Hypopygium (Fig. 27). Anal point dorsally is smooth and runs forward as a ridge a short distance onto the anal tergite; ventrally there is a narrow setigerous portion extending just over halfway to the tip. The inferior volsella is under the superior, strongly chitinized with three marginal setae. Adult female. No females were collected but some information was obtained from a developing female in a pupa; chitinization was at an early stage so some details could not be seen. Genitalia (Fig. 28). Similar to generic definition. Gonocoxapodeme VII joined mesally. Gonopophy- sis: dorsomesal lobe with long microtrichia, ventrolateral lobe broad with long microtrichia; apodeme lobe present, shape indistinct, with microtrichia. Gonocoxite IX too undeveloped to show seta. Notum thin with small ramus dorsal to anterior part of dorsomesal lobe of VIII. Post genital plate triangular, cercinormal, 155 nm. Seminal capsules ovoid, 109 um, ducts straight, with common opening. Pupa (N = 2 mounted). The specimens were whole pupae, not exuviae; dark brown in colour and strongly chitinized. Cephalothorax. Surface granulose, denticles broadly rounded. Cephalic tubercles unbranched, elon- gate, curved forwards with very small subterminal seta. No cephalic warts; thoracic horn plumose with many fine branches, basal ring oval; prealar tubercle blunt. Setation: Precorneals 2, antepronotals 2, dorsocentrals 2 pairs. Abdomen (Figs 29-31). Surface of all tergites and sternites I-VIII strongly reticulate (not shown in figures). Tergite I with no spines; II with hook row interrupted medially (Fig. 29); III-VI with posterior | row of about 20 irregular, strong spines. Pedes spurii B anterior on segment L, posterior on II (Fig. 29); pedes spurii A on IV. Sternite I with large anterolateral tubercles covered with triangular spines, and with wide anteromedial tubercle; posterior row of large spines on sternites I-VII. Segment VII without posterolateral spine or comb. Segment I without L setae, II-IV with 3, V-VI with 4 lamelliform L setae and VIII with 5. Anal lobe well developed with complete fringe of about 85 lamelliform setae and one dorsal lamelliform seta. Fig. 30 shows male from dorsal aspect and Fig. 31 shows female from ventral aspect. Larva (N = 12 mounted). Head Capsule length 0.6 mm. Antenna (Fig. 32). AR 1.25, basal segment slightly shorter than flagellum, blade arising in distal half of segment 2, accessory blade short. Lauterborn organs absent. Labrum. Very similar to that illustrated by Pinder & Reiss (1983), with blade-likeSIand SI. Pecten epipharynx (Fig. 33) a triangular plate divided into 3 lobes, central lobe pointed. Premandible with 5 teeth, brush present. Mandible (Fig. 34). Teeth almost black, seta subdentalis broad; seta interna present but not in figure. Pecten mandibularis absent. Mentum (Fig. 35). Teeth almost black except for pale central tooth; 6 lateral teeth; actual shape of medial portion could not be seen clearly on any specimens. Ventromedial plate wide, wrapping around head capsule laterally. Maxilla (Fig. 36). Palp large and long, a-seta present but b-seta could not be seen, chaetulae of palpiger reduced to 3, sensilla basicona long. Paraxial seta small, antaxial seta very long and curved, very few lacinal setae. Body. Claws of anterior parapod serrate, mostly long and thin, posterior claws simple. Anal tuber- cles short and conical. Specimens examined. Adults: 13 at lights, Lake Ziway, 81/4/15; 38d at lights, L. Awasa, 81/4/15; 15, at lights, L. Ziway 82/12/31;38d, at lights, L. Langano, 83/12/11; 18, swarming at dusk, near L. Abijata, 85/6/18. Pupae: 19 with larval exuviae attached, and 1?, L. Ziway, Jan. 1985. Larvae: Numerous specimens from L. Ziway (col. C. Tudorancea) during 1985, and from L. Awasa (col. ADH) during 1983. Comments. This species conforms closely to the generic definition but the pupa differs in that it has pedes spurii B on segment II and no posterolateral spines or combs on VII. It is notable that C. supplicans Meigen (Pinder & Reiss 1986, Langton 1984) also lacks these structures. The larva differs from C. sp. (Pinder & Reiss 1983) as the central lobe of the pecten hypopharynx has one point, not two; it also has a broad seta subdentalis on the mandible. McLachlan9s pupa is very similar; his figure of the larval mandible also shows the broad seta subdentalis, and his mentum is similar. Ecology. The larvae were found living in themuddy bottom of the shallow Lake Ziway (Tudorancea et al. 1989) and from the bottom of L. Awasa (Tilahun Kibret & Harrison 1989). McLachlan (1969) found them in a similar habitat on the bottom of L. Kariba, Zimbabwe. Distribution. Most of sub-Saharan Africa (Freeman 1957). Cryptochironomus sp. A One unassociated female was collected from Lake Awasa. Adult female (N = 1 mounted). Wing length 1.3 mm. Head. AR 0.7. Frontal tubercles minute. Palp segments 47, 40, 93, 124, 186 nm. 3 subapical sensilla on segment 3. Thorax. Scutal tubercle present. Setation: Lateral antepronotals nil, dorsocentrals 12, posterior prealars 4, scutellars 6 per side. Wing. Setation: Brachiolum 2, R 12, R, 6, R,,; 11, squama 14. Leg. LR fore 1.5, mid 0.5, hind 0.6. Sensilla chaetica on tarsomere 1: midleg about 50 biserial, hindleg nil. Genitalia (Figs 37, 38). Ventral ridge of VIII small. Dorsomesal lobe with long microtrichia; ventro- lateral lobes large; apodeme lobes (Fig. 37, left) with small chitinized base and microtrichia. Gonocoxa- podemes narrow and joined. Coxosternapodemes dark and curved. Gonocoxite IX with 2 setae. Segment X with 3 setae per side; postgenital plate pointed. Labia without microtrichia. Seminal capsules (Fig. 38) ovoid, 99 um long, ducts almost straight, wider in lower half and with common opening.