Aka tasmani Muir 1931
Creators: name: Löcker, Birgit
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Cixiidae
Aka
Aka tasmani

description: Aka tasmani Muir, 1931
(Figs 6 A–C, 16, 18)
Aka tasmani Muir, 1931: 63.
Types. Neotype, here designated, ♂, AUSTRALIA, Tas: Hobart, 5.vii. 1913 /43 (G.H. Hardy) (BMNH K45391). Paratypes. AUSTRALIA, Tas: 2 ♂, Hobart, 20.vii. 1913 /39 (G.H. Hardy) (BMNH K45388) (originally on one mount, now mounted on two separate mounts).
Other material examined. AUSTRALIA, Tas: 1 ♂, Thumbs Parallel Gullies, Sassafras, outer 3, 1.ix.1989 (H. Elliott) (ASCU).
Notes: Muir (1931) based this species on 4 females and 2 males from Hobart, Tasmania (G.H. Hardy, May, July, 1913) with „ type in Australian Museum, paratype in British Museum“.Three paratypes were found in the BMNH (Fig. 18). Enquiries for the types in the AMS and BPBM were unsuccessful which means part of the type series (3 specimens), including the holotype, is lost. Interestingly all of the paratypes in the BMNH are males, although Muir stated he had only 2 males. Mick Webb (BMNH) was able to match the paratypes with illustrations and the description given in this paper of a specimen from Thumbs Parallel Gully. A neotype has been designated to provide a diagnostic reference for the species.
Muir 1931 lists another female from the same location as the types, which was slightly larger and may also represent this species. This specimen could not be found and must have been lost together with parts of the type series.
Diagnosis. This species can be distinguished from all other Australian Aka by the following combination of characters: first tarsomere with 7 and second tarsomere with 6–7 apical teeth; lobes of male anal tube in lateral view produced into hooks; aedeagus right lateral with a medium sized spine (about half as long as flagellum) with its tip directed towards the flagellum; absence of a bifurcate spine on the aedeagus.
Colour. Vertex mid brown, with a whitish spot where subapical carinae meet lateral borders of vertex and near basal emargination. Face mid brown with a whitish spot at each lateral end of frontoclypeal suture; lateral carinae of postclypeus whitish near anteclypeus. Pro- and mesonotum brown with slightly paler carinae. Forewings light brown to whitish, with a few darker marks; costa with several mid brown bands; tubercles concolorous with cells; veins in general slightly darker than cells; pterostigma whitish. Legs light brown with a few darker marks.
Morphology. Body length: ♂ 4.4 mm.
Head: Vertex 1.1 x wider than long; median carina of vertex covering about 3/4 of basal compartment of vertex. Frons 1.1 x longer than wide; maximum width no more than 2x apical width; position of maximum width moderately dorsad of centre of frontoclypeal suture; median carina forked in basal (near frontoclypeal suture) third of frons. Median ocellus present. Anteclypeus lacking median carina. Subapical segment of rostrum 1.5 x longer than apical segment.
Thorax: Mesonotum with distinct sublateral carinae. Forewing 3.3 x longer than wide; costal margin with a several indistinct tubercles; tubercles never within cells; tubercles very small, concolorous with veins; tubercles not bearing setae; Sc+R+M near basal cell fused, forming a minute common stem; Sc+R+M fork of ScRA+ RP distinctly basad of fork CuA1+CuA2; distance tegula to ScR+M fork much longer than distance between this fork and ScRA+ RP fork; icu distinctly distad of apex of clavus; RP apically unforked; M not forked into MA and MP; nodus of y-vein slightly to moderately distad of centre of clavus; y-vein with A1 slightly elevated; 4 apical cells. Hind leg: 1st tarsomere with 7 apical teeth; 2nd tarsomere with 6–7 apical teeth and 3 fine setae.
Male genitalia: Anal tube (Figs 16 C,D, 18E,F) apically slightly excavated, starting to form two separate apical lobes; lobes in lateral view produced into hooks. Pygofer and genital styles as in Figs 16 E–G, 18E,F. Aedeagus (Figs 16 A,B, 18E,F): Phallotheca left laterally with a curved spine (a), right laterally with two spines (b,c). Flagellum unarmed, about the same width throughout.
Remarks. The male genitalia of the specimen from Thumbs Parallel Gullies matches those illustrated by Muir (1931) of A. tasmani, apart from a few minor details discussed below. Further it matches the description apart from the following character states. Muir lists, “No spines on the hind tibiae”. The specimen examined showed 3–4 medium sized lateral spines. The colouration deviates slightly from the description, with lighter coloured areas (marks) situated near the frontoclypeal suture, at the posterior end of the vertex and the anterior part of the pronotum. However, the light basal half of the costa, with three or four lighter marks on the apical half of the costal margin as described by Muir, can be observed in the specimen from Thumbs Parallel Gullies.
There is a certain degree of variation in the curvature, length and position of spines on the aedeagus. In two out of three specimens in the type series spines (b) and (c) are more pincer-like (Fig. 18 E) than in the third specimen (Fig. 18 F) and in the non-type-specimen from Thumbs Parallel Gully (Fig. 16 B) (pers. comm. Mick Webb, 2014). Because the pincer-like condition more closely resembles that of Muir’s illustration the neotype has been chosen from those two paratypes. Spine (b) is inserted closer to the ventral side in one of the paratypes (Fig. 18 F) than in the neotype (Fig. 18 E) and other paratype. The specimen from Thumbs Parallel Gully (Fig. 16 B) shows an intermediate state.
The ASCU collection holds a specimen, collected on the 4 April, 1989 in yellow pan traps at Mt Mangana on Bruny Island by J. Diggle and P. Greenslade, that has a configuration of aedeagal spines similar to A. tasmani and A. hardyi. Further it shares the presence of 7 apical teeth on the first and second tarsomere with the specimen from Thumbs Parallel Gullies. However, it differs from that one, and the original description of A. tasmani, in the absence of well developed triangular spines on the anal tube (the lobes are only slightly produced), the forking of M, the evanescent sublateral (medio-lateral) carinae on the mesonotum and the colouration. The specimen from Bruny Island is very pale in colour with clearly contrasting light and dark brown marks. It has very distinct dark tubercles which are not present in the Thumbs Parallel Gullies specimen and which are not mentioned in Muir’s description. Further studies are needed to clarify whether this specimen belongs to A. tasmani, A. hardyi or represents a new species closely related to those two.
description: Published as part of Löcker, Birgit, 2015, Revision of the Australian species of Aka White, 1879 (Fulgoromorpha: Cixiidae) with the description of a new genus, pp. 199-223 in Zootaxa 3956 (2) on pages 217-219, DOI: 10.11646/zootaxa.3956.2.3, http://zenodo.org/record/246048