Key to larvae of Pharaxonotha floridana, P. kirschii and known larvae of Cycadophila

Analysis of the 16S rRNA gene revealed an identical match between one specimen of a newly recognized larval morphotype collected in a male cone of Cycas petraea (D0331 in Fig. 1) and adult Cycadophila (Strobilophila) tansachai found in Cycas petraea, C. elephantipes and C. pectinata. A second sample of this larval morphotype (D0333 in Fig. 1) from a male cone of C. pectinata in Thailand, however, did not match these sampled adults. Based on this analysis this larval morphotype is placed in subgenus Strobilophila, but is not assigned to a specific species. The unmatched Strobilophila larva may correspond with Cycadophila (S.) yangi, one of two species of adults of subgenus Strobilophila found together on the cones of Cycas pectinata in Thailand [see also Remarks under description of C. (S.) yangi]. The key to larvae below includes our new morphotype of Cycadophila (Strobilophila) spp., two species of Cycadophila (Cycadophila) previously described by Xu et al. (2015) and two other larvae of Pharaxonothinae including Pharaxonotha kirschii (illustrated by Böving & Craighead 1930) and Pharaxonotha floridana.

1. Paired tubercles t1 anterior to urogomphi on A9 without apical hook, but with a short subapical spine pointing posteriad or with apical hook and subapical spine both absent............................................................ 2

- Paired tubercles t1 anterior to urogomphi on A9 (Figs. 3 C–F, 15C–D) each with an apical hook, shaped like a bird head, pointing posteriad..................................................................... Cycadophila sp. ... 3

2. Paired tubercle t1 with a short subapical spine pointing posteriad (Figs. 3 A–B).......... Pharaxonotha floridana (Casey)

- Paired tubercle t1 without a subapical spine........................................ Pharaxonotha kirschii Reitter

3. Urogomphi length measured from tubercle t3 (Fig. 3 C–D) <length of segment A9; tubercle t1 anterior to urogomphi with base tilting in antero-dorsal direction away from apices of urogomphi (Fig. 3 C); mandibles with dorsal incisor serrate (Fig. 3 I)....................................................... Cycadophila (Cycadophila) debaonica Xu, Tang & Skelley

- Urogomphi length measured from tubercle t3 (Fig. 3 E–F) = or>length of segment A9; tubercle t1 anterior to urogomphi with base vertical or tilting in postero-dorsal direction toward apices of urogomphi (Figs. 3 E, 15C); incisors of mandible not serrate (Figs. 3 H, 15F)...................................................................................... 4

4. Length of antennomere II ~ 2× own width (Fig. 3 G); sclerotized dorsal plates on abdominal segments A1–A8 with 2 pairs of tubercles along posterior margin, tubercle color brown, slightly darker than dorsal plates (Fig. 3 F); turbercle t3 on A9 prominent in dorsal view, larger than t2 (Fig. 3 F)............ Cycadophila (Cycadophila) fupingensis Skelley, Tang & Xu

- Length of antennomere II ~ 3× own width (Fig. 15 E); sclerotized dorsal plates on abdominal segments A1–A8 with 5–6 pairs of tubercles along posterior margin, tubercles light-colored, contrasting with brown of dorsal plates (Fig. 15 D); turbercles t2 and t3 on A 9 in dorsal view equal in size (Figs. 15 D)...................... Cycadophila (Strobilophila) new subgenus