Asphondylia silva, Dorchin & Joy & Hilke & Wise & Abrahamson, 2015, Dorchin & Joy & Hilke & Wise & Abrahamson, 2015

Dorchin, Netta, Joy, Jeffrey B., Hilke, Lukas K., Wise, Michael J. & Abrahamson, Warren G., 2015, Taxonomy and phylogeny of the Asphondylia species (Diptera: Cecidomyiidae) of North American goldenrods: challenging morphology, complex host associations, and cryptic speciation, Zoological Journal of the Linnean Society 174 (2), pp. 265-304: 286-288

publication ID

http://doi.org/ 10.1111/zoj.12234

persistent identifier

http://treatment.plazi.org/id/81198784-FF92-FFF5-91D9-8AA7F98DF9AF

treatment provided by

Felipe

scientific name

Asphondylia silva
status

SP. NOV.

ASPHONDYLIA SILVA   DORCHIN SP. NOV.

Host plants

Solidago caesia   .

Gall and biology

This species induces very small, single-chambered galls in apical shoot tips ( Figs 19, 20 View Figures 15–22 ). The gall is composed of several very short leaves that are pressed together to form a conical chamber, the internal walls of which are lined by a white layer of mycelium. Each gall contains a single larva. Galls are 4.5–7.5 mm long and 1.5–3.0 mm wide, and are barely noticeable. They may be very common in some localities, but absent in others. The species has at least two generations between June and September; galls were first apparent in early June and adults emerged from them in early July. In early September, galls were found among flower buds on the shoot tips, and all were already empty, some with pupal skins stuck in them ( Fig. 20 View Figures 15–22 ). This species is heavily parasitized, and thus very few galls yielded adult midges in the laboratory. Out of six regularly surveyed localities in central PA, galls were found in only two (Shikellamy State Park and Dale’s Ridge), where they were consistently abundant.

Adult

Characters as in A. monacha   , except for the following.

Head: Flagellomere 1/flagellomere 5 ratio = 1.09–1.23 in male (N = 3), 1.41–1.56 in female (N = 4).

Thorax: Wing length 2.37–2.63 mm in males (N = 3), 2.15–2.51 in females (N = 4).

Female abdomen ( Fig. 58 View Figures 55–61 ): Sclerotized part of ovipositor 2.15–2.24 times as long as sternite 7 (N = 4).

Male terminalia ( Fig. 59 View Figures 55–61 ): Aedeagus about same width throughout length, slightly tapered towards rounded apex. Hypoproct with very shallow notch apically.

Larva (third instar)

Orange; integument covered by small bumps. Length 2.02–3.26 mm (N = 6). Antennae about 1.0–1.5 times as long as wide; cephalic apodeme as long as head capsule. Spatula shape variable ( Figs 60, 61 View Figures 55–61 ), lateral teeth longer than median teeth, gap between median teeth as deep as, or clearly deeper than, gaps between lateral and median teeth, shaft thick and well sclerotized.

Pupa ( Figs 74, 75 View Figures 70–77 )

Characters as in A. monacha   , except for the following. Antennal horns long and slender, only slightly curved, apices pointed and finely serrated in frontal view.

Diagnosis

This is the second smallest Asphondylia species   from goldenrods and the only one that is found on S. caesia   , hence it can be easily recognized from its host and tiny bud gall. Other than their size and the slightly different shape of the male hypoproct, adults of this species do not differ morphologically from those of A. solidaginis   , A. rosulata   sp. nov., and A. pseudorosa   sp. nov., but molecular data consistently indicate that this is a distinct species most closely related to A. rosulata   sp. nov.

Etymology

The name silva   (Latin for forest) refers to the typical habitat in which this species is found.

Type material

Holotype: ♂, USA, PA, Shikellamy State Park , 30 July 2007, N. Dorchin and M.J. Wise, from S. caesia   bud gall ( TAUI).  

Paratypes: 1 larva, USA, PA   , Dale’s Ridge , 18 June 2006, N. Dorchin   ; 6 larvae, USA, PA   , Dale’s Ridge , 19 June 2006, N. Dorchin; 4 exuviae, USA, PA   , Shikellamy State Park , 30 June 2007, N. Dorchin   ; 1 larva, 1♂, USA, PA   , Dale’s Ridge , 5 July 2007, N. Dorchin and D. Ryan; 1 exuviae   , 1♂, 4♀, USA, PA   , Shikellamy State Park , 30 July 2007, N. Dorchin and M.J. Wise (exuviae and 1♀ USNM, others TAUI)   .

PA

Universidade Federal do Oeste do Pará

USNM

Smithsonian Institution, National Museum of Natural History