Lithosmylidia sp.

Lambkin, Kevin J., 2024, Fossil insects of the Middle Triassic Gayndah Formation of south-eastern Queensland, Memoirs of the Queensland Museum | Nature 65, pp. 30-46 : 41-44

Lithosmylidia sp. ( Fig. 6C)

Material: Indistinctly preserved forewing fragment, QMF61221a/b.

Notes: The fragment is similar in size to L. baronne , and the basic form of the terminal branches of Cu is similar to all three species of Lithosmylidia (and other Archeosmylidae — ‘few branched, often pectinate, but [the] branches are very oblique and not as strongly pectinate as in Osmylidae’ ( Makarkin et al. 2014b)). From what can be made out in the specimen, the details of the branching pattern of both CuA and CuP appear to differ from those of L. baronne and L. lineata , but bear some similarity to those of the smaller species, L. parvula . Notwithstanding, the specimen is too poorly preserved to be adequately diagnosed, so is simply left as Lithosmylidia sp.

Family OSMYLOPSYCHOPIDAE Martynova, 1949

Gayndahpsychops Lambkin, 2014

Gayndahpsychops carsburgi Lambkin, 2014

Material: Holotype QMF57532 ( Lambkin 2014a) remains the only known specimen.

Indeterminate NEUROPTERA sp. ( Fig. 7A–D)

Material: Three imperfectly preserved forewing fragments, QMF61222a/b, 61223a/b, 61239a/b.

Notes: The three specimens are of the same species. On the basis of multiple costal veinlets, presence of a recurrent humeral vein, a multibranched pterostigma area, RP with four pectinate branches, and M extensively branched, it is considered a neuropteran, but further determination has not been possible. The small size (length c. 7.5 mm) and venation is suggestive of a berothid with simplified venation, similar to the Jurassic Krokhathone Khramov, 2015 , from Kazakhstan ( Fig. 2 in Khramov 2015), although Sc runs to the costal margin in the Gayndah specimens, rather than merging or at least appearing to merge with RA apically as is typical of the Berothidae .

Order COLEOPTERA Linnaeus, 1758 ( Fig. 8A–G)

Material: Complete or fragmentary single elytra: QMF: 61224a/b (finely punctate), 61225 (very finely striate, L (length of elytron) 5 mm), 61226 (smooth), 61227 (strongly striate, L 1.9 mm) ( Fig. 8A), 61228 (smooth), 61229 (punctate/striate, L 5.2 mm) ( Fig. 8B), 61230 (punctate/striate, L 12 mm), 61231 (smooth, L 2 mm) ( Fig. 8C), 61232 (faintly striate, L 3 mm), 61233 (punctate/striate), 61234 (smooth, L c. 2 mm), 61235 (finely striate, L 3 mm), 61236 (smooth), 61237 (striate), 61238a/b (cupedoid), 61240 (punctate/striate, L c. 2.5 mm), 61241 (smooth, L < 2 mm), 68242 (punctate/striate, L c. 3 mm), 61243 (cupedoid, L < 8 mm), 61215 (cupedoid, L> 5 mm) ( Fig. 8D). Complete or fragmentary paired elytra: 61244a/b (punctate, + whole body, antenna and part foreleg, L 10.7 mm) ( Fig. 8E), 61245a/b (cupedoid, L 6.2 mm) ( Fig. 8F), 61246a/b (cupedoid, + metathorax, L 10.2 mm) ( Fig. 8G), 61247 (smooth, + pterothorax and abdomen), 61248 (smooth, + pronotum, L c. 2 mm), 61249 (smooth, + metathotrax and abdomen, L c. 2.5 mm), 61250 (punctate/striate), 61251 (striate, + part pronotum, L 2.5 mm), 61252 (cupedoid, + punctate abdomen, L> 10.5 mm).

Notes: Based simply on surface ornamentation and size, the list suggests the presence in the fauna of possibly three cupedoid species, three species with striate elytra, two with punctate/striate elytra, one with punctate elytra, and one with smooth elytra.

Order MECOPTERA Packard, 1886

Family MESOPSYCHIDAE Tillyard, 1917

Mesoses Riek, 1976

Mesoses gayndah Lambkin, 2014

Material: Holotype QMF57544 ( Lambkin 2014b) remains the only known specimen.

Family PERMOCHORISTIDAE Tillyard, 1917

Mesochorista Tillyard, 1916

Mesochorista sp. ( Fig. 9A, B)

Material: Forewing fragment, QMF61253a/b.

Notes: The specimen preserves the anterior apical quarter of a forewing, which in size and venation perfectly matches Mesochorista proavita Tillyard, 1916 , recorded from Denmark Hill and particularly Mount Crosby where it is the most frequently collected mecopteran ( Riek 1955). Notwithstanding its congruence with M. proavita , not enough of the wing is preserved to ascribe the fragment with certainty to that species.

Order TRICHOPTERA Kirby, 1813

Family PRORHYACOPHILIDAE Riek, 1955

Prorhyacophila Riek, 1955

Prorhyacophila colliveri Riek, 1955 ( Fig. 9C, D)

Material: Incomplete forewing QMF61254, and a more fragmentary forewing, QMF61255, the latter tentatively referred to the species.

Notes: The incomplete forewing — QMF61254 ( Fig. 9C, D) — is 4.1 mm long, suggesting a total length of just over 5 mm. Prorhyacophila and the family Prorhyacophilidae are known from three species — the genotype P. collieri Riek, 1955 , from Mount Crosby, P. furcata Sukatsheva, 1973 , from the Middle Triassic of Kyrgyzstan, and P. rasnitsyni Sukatsheva & Aristov, 2013 , from the Late Permian of Russia ( Riek 1955, Sukatsheva 1973, Sukatsheva & Aristov 2013).

A second Australian species, originally described as Eocorona iani Tindale, 1980 , in the Lepidoptera , was transferred to Prorhyacophila by Sukatsheva (1982) based on Tindale’s (1980) description and figures. A re-examination of the holotype of E. iani (UQC2327a/b), however, has revealed that the specimen bears little resemblance to Tindale’s description and figure ( Fig. 4a in Tindale 1980) — the anterior basal ¼ of the wing is lacking, only the anterior section of RP is clearly preserved and appears pectinate, M and the rest of RP in the central part of the wing are broken and overlaid and cannot be clearly identified, CuA appears to be simple, there is no jugal lobe, and importantly the anal veins are simple, not looped. The specimen is almost certainly a mecopteran, possibly a species of Neoparachorista Riek.

As noted by Sukatsheva & Aristov (2013) the species of Prorhacophila all have similar forewing venation, and are diagnosed chiefly on the relative positions of the forks of RP and M. In this character, its size and its crossvein field, QMF61254 is almost identical with P. colliveri , the only difference being the position of the RP 3+4 fork — basal to (or in QMF61255 slightly distal to) RP 1+2, as opposed to quite distal to RP 1+ 2 in the only previously recorded specimen of P. colliveri (Fig. 17 in Riek 1955). The position of the fork of RP 3+ 4 in P. colliveri is, however, quite variable as revealed by a series of new specimens collected by the author at Mount Crosby. It can be quite distal to (as illustrated by Riek), just distal to, or at about the same level as that of RP 1+2. In light of this variability, QMF61254 and possibly also 61255 from Gayndah are referred to P. colliveri .

Prorhyacophila was synonymised by Ansorge (2002) with Mesotrichopteridium Handlirsch, 1906 , from the Early Jurassic of Germany. Even though the forewings of the two genera have many resemblances, the synonymy was not adopted by Sukatsheva & Aristov (2013) nor herein, with the preference to retain Prorhyacophila for its Australian genotype. The phylogenetic position of the Prorhyacophilidae has also been subject to debate with Ansorge (2003) and Minet et al. (2010) arguing that the family is a stem group of the higher order group Amphiesmenoptera ( Trichoptera + Lepidoptera ) rather than true Trichoptera . Sukatsheva & Aristov (2013) on the other hand have maintained the Prorhyacophilidae as one of their five families of the suborder Protomeropina Tillyard, 1926 , within the Tricoptera. Without any particular predilection one way or the other, the latter position has been adopted herein.

Fossil insects of the Middle Triassic Gayndah Formation of south-eastern Queensland