New Aethaloptera BRAUER Species
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Opusc. Zool. Budapest, 2018, 49(1): 03–16 Species delineation and description in Aethaloptera Brauer genus by phallic head (Trichoptera, Hydropsychidae, Macronematinae) J. OLÁH János Oláh, residence postal address: Tarján u. 28, H-4032 Debrecen, Hungary. E-mail: [email protected] Abstract. Taxonomy of the “widely distributed and highly varying species” in the small Aethaloptera genus was questioned long ago. Relying on the macro morphology, detectable by the routine resolution of the stereomicroscope, these species look very similar. However, applying the higher resolution of compound microscope with focusing on profile stability, significant shape divergences have been recognised in the fine structure of the speciation trait that is in the much specialised head structure of the phallic organ. The ancestral prototype of caddisfly genitalia is highly modified in the Hydropsychidae family. The hydropsychid prototype is further organised in the macronematine Aethaloptera genus: the abbreviated primordial genital structures of Hydropsychidae family are retracted into the invaginated tip of the phallotheca with apomorphic organisation of complexity by reduction or simplification, a complexity integrated by incremental subtraction. Examining the fine phenomics of the phallic head we have tripled the species number in this small genus and delineated altogether 12 species. We expect many more species to be collected and distinguished in this neglected genus by the fine structure of this speciation trait. Here we established two new species groups: Aethaloptera dispar new species group and A. meyi new species group and described five new species: Aethaloptera felalla, A. karima, A. malickyi, A. meyi and A. wellsi spp. nov. Keywords. Speciation trait, fine phenomics, incremental subtraction, new Aethaloptera species. INTRODUCTION Lestage (1936) doubted that Aethaloptera dispar was the same species throughout Africa. Support- he Aethaloptera Brauer, 1875 genus belongs ing this view Marlier (1943) stated that there were T to the Polymorphanisini tribe of the long- at least three types of this widely distributed Afri- horned hydropsychid Macronematinae subfamily. can species present just in Belgian Congo. Kim- In its present taxonomic state this is a small genus mins (1962) took an opposite view, suggesting comprised of four known species. Two species, A. that even Aethaloptera dispar and A. maxima may dispar Brauer, 1875 and A. maxima Ulmer, 1906 be only local forms of one widespread species. occur in the Afrotropical Region. One species, A. Malicky (1998) has found unreliable to separate evanescent (McLachlan, 1880) is present in the A. gracilis from A. sexpunctata in the Oriental East Palearctic Region. One species, A. sexpunc- region. Studies on larval morphology indicated tata (Kolenati, 1859) is distributed both in the that other species are also present in the Afrotro- Oriental and Australasian Regions. They are pical populations besides A. dispar and A. maxima usually treated as “widely distributed and highly (Statzner & Gibon 1984, Ogbogu 2005). In his ge- varying” species: A. dispar has been recorded nus revision Barnard (1980) has concluded the from the entire Afrotropical Region south of the lack of useful diagnostic genitalic characters in Sahara and A sexpunctata (Barnard, 1980) has the Aethaloptera genus at generic and species even a larger distributional area from India to level compared to characters found on wings and Australia. thorax (Barnard 1980). The taxonomy of these “widely distributed and We have collected long series of Aethaloptera highly varying” species was questioned long ago! sexpunctata in several habitats near the locus _______________________________________________________________________________________________________ urn: lsid:zoobank.org:pub:3B1F90F0-6D8C-469E-82C4-9AE17977A2E0 published: 24 January 2018 HU ISSN 2063-1588 (online), HU ISSN 0237-5419 (print) http://dx.doi.org/10.18348/opzool.2018.1.3 Oláh: Species delineation and description in Aethaloptera genus by the phallic head typicus in East India (Orissa) as well as a single have low diversity and wide range of variation. male specimen from Vietnam. Superficially, re- For instance the fork 4 on forewing, whether lying on the macro morphology detectable by the sessile or stalked, is highly variable even inside routine resolution of the stereomicroscope, the populations. This is the common nature of neutral Indian and Vietnamese specimens look very simi- traits, directly exposed to random impacts of ef- lar. However, applying the higher resolution of fective population size, genetic drift and recom- compound microscope and focusing on profile bination. Contrary, the diversity of the phallic stability we have found significant shape diver- head is high and these fine structure divergences gences in the fine structure of the speciation trait are very stable, not variable. These diverse and that is in the much specialised head structure of stable character states are the direct evidences of the phallic organ. This discovery inspired us to contemporary, recent past adaptive divergences. realise a systematic survey on all of the available The stability of these adaptive non-neutral specia- Aethaloptera materials. In this paper we have tion traits is organised and maintained by several tripled the species number in this genus and de- integrative and protective mechanisms (Oláh & lineated 12 species based upon our very limited Oláh, 2017). In this genus the phallic head with material. We suppose that many more species are diverse and stable shape divergences represents waiting to be collected and distinguished by spe- the adaptive, non-neutral speciation trait organ- cialised systematic collecting efforts and by de- ised by integration during the sexual processes of tecting the divergences in the fine structure of the speciation and resulted in reproductive barrier speciation traits. building. The phallic head of Aethaloptera is characterised by much specialised apomorphic Fine structure of the speciation trait state of abbreviated and retracted terminal struc- tures, compared to the plesiomorphic state of the Fine phenomics is not just a more powerful endotheca present in the ancestral arctopsychine procedure of magnification applying compound subfamily, in ancestral macronematine genera, microscope of much higher resolution instead of like Leptonema and in most genera of hydro- routine stereomicroscopy. It is right that applying psychine subfamily. In the genera of Hydro- higher resolution to visualise, discern and draw psychinae subfamily an inverted endophallus or, the fine structures of phenomics significantly im- as argued by Korecki (2006), an inverted phalli- proves our capacity to find the adaptive early cata (aedeagus) is present in the form of internal shape divergences of initial splits in reproductive atrium inside the phallotheca. But we have to barrier buildings. But fine phenomics could be remind that all extant species are a mix of an- efficiently applied with lower resolution of stereo- cestral and derived characteristics and not the microscopy if our focus is properly and ade- extant organism is ancestral/primitive/branched quately directed to the subtle and stable shape early or derived/young/branched off last (Omland divergences, like the lateral profile of the phallic et al. 2008). head detectable also at lower magnification in Aethaloptera. In the routine practice of gross phenomics these small divergences are usually The ancestral prototype of the caddisfly phal- neglected and interpreted as variations and not as lus has a well sclerotized phallobase (or phallo- building of reproductive barriers in early diver- theca), an apical tubular aedeagus (sclerous phal- gences. Stability of “small divergences” appears licata) and they are connected and mobilised by a convincing and very demonstrative if we examine membranous flexible endotheca supplied with population samples with several specimens and endothecal processes (parameres). This tripartite put together in matrices as we have realised here tubular telescopic structure is traversed through at species with more specimens. by the sperm duct, the slender tubular ductus ejaculatoricus and discharges into the endo- In the Aethaloptera genus the gross mor- phallus through the gonopore. The endophallus or phology of genitalia, as well as the wing venation directly the sperm duct discharges into the vaginal 4 Oláh: Species delineation and description in Aethaloptera genus by the phallic head chamber through the pore of the phallotreme sence of variously widened atrium-like endophal- operated or regulated by a pair of phallotemmal lic structure is questionable. Especially its dorsum sclerites. frequently appears diffuse. Its ventrum is discern- ible due to the presence of a more discernible Compared to this ancestral prototype, the phal- structure similar to the pigmented sclerous band lic structure of the Hydropsychidae is highly mo- located alongside in hydropsychine genera. The dified. The phallotheca is elongated and the basic endophallus or the ejaculatory duct seems to emp- telescopic architecture of endotheca, aedeagus and ty through the apical opening of the phallotreme. endothecal processes is restructured. They have been abbreviated or highly reduced and moved in Fine structure of the abbreviated and invagi- terminal position to the very distal end of the nated primordial components. The sperm dis- phallotheca. In spite of these modifications these charging opening,