New combiNatioNs of afrotropical chiroNomiNi ( Diptera : chiroNomiDae )

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Introduction
Paul Freeman contributed considerably to the knowledge of Afrotropical Chironomidae through his four monographs on Chironomidae south of the Sahara (Freeman 1955, Freeman 1956, Freeman 1957, Freeman 1958).These contributions from the 1950s summarized the contemporary knowledge of Afrotropical Chironomidae and provided an excellent basis for future work and revisions.A number of species new to science were described by Freeman in these and subsequent works, and Freeman still holds the authorship for almost 30% of all the currently known species from the Afrotropical Region.Later taxonomic revisions have changed the generic placement of 80 species, but more than 90 species retain Freeman's original generic assignments.It should be noted that Freeman's original descriptions were based on adult morphology only; contemporary generic assignments can be enhanced by descriptions of immature stages as well as use of molecular taxonomic techniques.
A large initiative to publish a Manual of Afrotropical Diptera was initiated by Ashley Kirk-Spriggs and officially launched at the 7th International Congress of Dipterology, San José, Costa Rica in 2010 (http://afrotropicalmanual.org).As part of our work on the chapter of Afrotropical Chironomidae (Ekrem et al. in press), type material of four Chironomini species described by Freeman were examined to re-evaluate the generic placement: Chironomus (Cryptochironomus) inflexus Freeman, 1957; Chironomus (Endochironomus) hamatus Freeman, 1957;Chironomus (Endochironomus) pruinosus Freeman, 1961 and Chironomus (Endochironomus) woodi Freeman, 1957.These species were specifically selected for evaluation as they were particuarly difficult to classify under current generic concepts.

Material and methods
Nominal types as well as other material were sought in the Natural History Museum, London, UK (NHMUK), Muséum national d'Histoire naturelle, Paris, France (MNHN), and the Department of Natural History, University Museum of Bergen, Bergen, Norway (ZMBN).Most of the specimens were already mounted on slides when we received them, but the holotype of Chironomus (Endochironomus) pruinosus was mounted in Euparal by us according to the procedure described by Pinder (1989).
Digital photographs were taken with a Leica DFC420 camera mounted on a Leica DM6000 B compound microscope using bright field or Nomarski DIC and the software Leica Application Suite.
The examined male paratype shows characters typical of the Chironomus group of genera: antenna with 11 flagellomeres, medially fused antepronotal lobes, inferior volsella subcylindrical with dense apical setae.Unfortunately, the slide-mounted hypopygium (Figs 1a, b) is quite distorted, but the almost parallel-sided gonostylus without subapical constriction, anal tergite bands that meet medially in front of and not encircling median tergite setae, and the shape of the superior volsella resembles what is known from Benthalia Lipina (Shilova 1980 sub Einfeldia carbonaria (Meigen, 1804), Saether 2012).Moreover, the specimen has large barrel-shaped frontal tubercles (Figs 1c, d) characteristic of Benthalia (Shilova 1980, fig.8A 2 ).In addition there is a smaller pair of warts on the anterior part of vertex, dorsolaterally with respect to the frontal tubercles.A similar arrangement has been recorded for Tanytarsus epleri Ekrem et al., 2003.For this species the pupa has large frontal warts in addition to enlarged frontal tubercles (Ekrem et al. 2003), thus similar structures might be present in the unknown pupa of Chironomus (B.) hamatus.Cladopelma inflexum (Freeman, 1957) Chironomus (Cryptochironomus) inflexus Freeman, 1957: 403.
The species was listed as a new combination in Cladopelma Kieffer by Freeman and Cranston (1980), but later transferred to Cryptotendipes by Ashe et al. (1987) based on personal communication with P. S. Cranston.We have examined the male holotype (pinned specimen with hypopygium on separate celluloid strip) and a slide mounted female paratype (Fig. 2).The presence of small frontal tubercles (Figs 2c, d), male gonostyli with a narrow base (Fig. 2a) and setae ventrally on segment X of the female abdomen (Fig. 2b) points towards placement in Cladopelma.The gonocoxal appendages of the holotype can be interpreted as a small wart-like superior volsella above a weak lobe-like inferior volsella (Fig. 2a), but this is not a completely clear structure on both sides.The presence of an inferior volsella is not compatible with the present diagnosis of Cladopelma (Cranston et al. 1989,Yan et al. 2008), but more material of C. inflexum, including associated immatures, should be examined before eventual emendations to diagnostic characters of Cladopelma are made.The species is known as adults from Chad, Malawi, Niger and Sudan (Freeman andCranston 1980, McLachlan 1975).(Freeman, 1961)  Endochironomus pruinosus (Freeman, 1961), Freeman and Cranston (1980).

Kiefferulus pruinosus
Material examined: Holotype male (MNHN), Madagascar Nord, Montagne d'Ambre 1000m, 23.xi-4.xii.1958, B. Stuckenberg.The male holotype lacks frontal tubercles, has numerous setae on vein R in an otherwise bare wing (Fig. 3a), and has divided mid-and hind tibial combs, each with spur.Antenna with 11 flagellomeres and an AR of about 2.7.The hypopygium (Fig. 3b) lacks median tergite setae, has Y-shaped anal tergite bands, almost bare superior volsella, setose inferior volsella that is slightly expanded dorso-ventrally and gonostylus with slight subapical constriction.The species fits quite well in the definition of Kiefferulus Goetghebuer after the inclusion of Nilodorum Kieffer by Cranston et al. (1990).Indeed Freeman (1961) had discussed the similarity with Nilodorum in the original description, especially with regard to the appearance of the thorax (Fig. 3c).He chose not to place the species there due to the normally developed maxillary palps and the narrow inferior volsella, but these characters later have been argued not to be diagnostic at genus-level (Cranston et al. 1990).The shape of the superior volsella (Fig. 3b) is quite aberrant compared to other species in Kiefferulus, but we interpret this as a species-specific trait.Synendotendipes woodi (Freeman, 1957) comb.n.