Cimbrophlebia flabelliformis, Archibald, Bruce, 2009

Archibald, Bruce, 2009, New Cimbrophlebiidae (Insecta: Mecoptera) from the Early Eocene at McAbee, British Columbia, Canada and Republic, Washington, USA, Zootaxa 2249, pp. 51-62: 52-54

publication ID

http://doi.org/ 10.5281/zenodo.190747

persistent identifier

http://treatment.plazi.org/id/DB728788-FF86-FFD7-FF6E-FB6BFE31FB56

treatment provided by

Plazi

scientific name

Cimbrophlebia flabelliformis
status

sp. n.

Cimbrophlebia flabelliformis  , sp. n.

( Fig. 1View FIGURE 1 A –B)

Diagnosis. Wing distinguished from those of other Cimbrophlebia  species by the following: 1), 2 A morphology: four pectinate branches separates it from C. bittaciformis  , [seven branches: three basal branches pectinate, four distal branches dichotomous], C. leahyi  [six branches: two basal branches pectinate, minimum of four dichotomous distal branches], not known to be distinct from C. brooksi  , C. westae  , where 2 A is little known by preservation; 2), Shape: length about four times width separates it from C. brooksi  [distinctly narrower: length about five times width], C. bittaciformis  [similarly slender (see remarks)], ( C. leahyi  , C. westae  length also about four times width); 3), Colouration distinct from that of C. brooksi  , C. westae  , C. bittaciformis  (see below); closest to that of C. leahyi  (as below) differing from C. leahyi  by more overall dark colouration, including 2 A region [ C. leahyi  : light], further differentiated from C. leahyi  by distinctly round / oval light spots [ C. leahyi  : differing position, sizes of more irregularly shaped light spots], (see descriptions, remarks, Figs. 1View FIGURE 1 A; 2 A, B; 4 A, C; 6 A, C; 7 A).

Description: holotype wing. As in diagnosis, Fig. 1View FIGURE 1 A, B, and the following. Length 28 mm, width 7 mm. Colouration as in Fig. 1View FIGURE 1 A: dark, with eight light spots (possibly more in basal-most region?) four along anterior portion, basal two smaller, distal two larger; four smaller spots along posterior portion. Sc: Sc 1 terminates on C ~ 2 / 3 wing length; Sc 2 separates from R 1 at pterostigmal region, joins with C at steep angle. R 1 branched, curved around pterostigma to join C. Rs with four dichotomous branches. M with four dichotomous branches; not preserved in basal quarter of wing. Branching of Cu 1, Cu 2 not preserved; Cu 1 long, straight, until 2 / 3 wing length, bent posteriad at m-cu to hind margin; Cu 2 straight for preserved portion, close to Cu 1, not preserved distad bend of Cu1. 1A: long, straight, close to Cu 2 in basal 2 / 3 of wing, apicad gently bent posteriad, meeting hind margin. 2 A with four pectinate branches (second branch with crossvein to posterior margin). 3 A: not detected. Few crossveins detected as preserved ( Fig. 1View FIGURE 1 B).

Type material. Holotype: UCCIPR L- 18 F- 763 (part), UCCIPR L- 18 F- 764 (counterpart). A well preserved fore- or hind wing; housed at TRU; labelled: Holotype Cimbrophlebia flabelliformis, Archibald, 2009  . Collected by unknown person at McAbee in 2002, donated to TRU by David Langevin, 2002.

Locality and age. McAbee, British Columbia, Canada; Early Eocene.

Etymology. The specific epithet flabelliformis  is formed from the Latin flabellum, “fan”, and forma, “shape”, referring to the overall impression of the somewhat evenly separated wing veins, radiating apicad in a fan-like manner.

Remarks. The configuration of the basal portion of 2 A seen in C. flabelliformis  and C. sp. A corresponds with the vein fragment of C. bittaciformis  previously identified as 3 A ( Willmann, 1977: Fig. 2View FIGURE 2) and subsequently with uncertainty ( Willmann, 1989: Fig. 135), indicating that this similarly-placed vein on C. bittaciformis  may also be a portion of 2 A.

The wing of C. flabelliformis  is about four times as long as wide, as is that of C. leahyi  (see bottom wing in Fig. 2View FIGURE 2 C), C. westae  , and apparently C. sp. A judging by the shape of its preserved portion. This is distinct from the more slender wings of C. brooksi  , length / width about 4.9, and C. bittaciformis  (width not reported, but these appear distinctly long and slender: see Willmann, 1977: Fig. 1View FIGURE 1, complete wings of the holotype, and Fig. 2View FIGURE 2, incomplete wing of the paratype). These are confidently not simply forewing / hind wing differences, as shape appears reasonably consistent between them (comparable in C. leahyi  and C. bittaciformis  ).

The lengths of complete (or mostly so) cimbrophlebiid wings vary from about 25 to 38 mm: C. westae  ~ 25 mm; C. flabelliformis  , 28 mm; C. leahyi  : ~ 31 mm; C. bittaciformis  , hind wing 31.5 mm and forewing 34.5 mm; C. brooksi  , ~ 38 mm. These differences, however, fall within variation found in the scorpionfly Panorpa communis ( Ohm, 1961)  ; further, where known, hind wings are a bit smaller than forewings. Only the great size differences between that modelled for the incomplete wing of C. sp. A (estimated as> 40 mm long) and the much smaller C. flabelliformis  and C. westae  are here considered meaningfully distinctive, given current knowledge.

The holotype of C. flabelliformis  bears four branches of Rs, unlike those of C. leahyi  , C. brooksi  , and C. westae  , which have five branches. Willmann (1977) found this character to be plastic within C. bittaciformis  (and see P. communis: Ohm, 1961  ), and so this is not considered diagnostic here.

Wing colouration of the Okanagan Highlands species may be separated into three groups: 1), that of the McAbee species C. flabelliformis  and C. leahyi  ; 2), of C. brooksi (Republic)  ; and 3), of C. westae (Republic)  . C. flabelliformis  and C. leahyi  have variations of a general pattern consisting of mostly dark wing, with a series of large, irregular to oval light spots extending along the length of the anterior portion of the wing, touching the anterior margin: the smallest one or two in the basal quarter, a large one at about mid-wing, and a large one between this and the apex. There are various smaller spots along the posterior half of the wing. The preserved portion of C. sp. A indicates that it may belong to this group.

The colouration of the C. westae  wing is somewhat similar to that of the McAbee species, but with more, exaggerated light regions, which extend the length of much of the posterior wing as known, and a further light band apicad the large spot in the corresponding position of the apical-most one of C. flabelliformis  and C. leahyi  . The resultant remaining dark colouration is arranged as a lengthwise zigzag touching the anterior, but not posterior margin ( Fig. 6View FIGURE 6 C). Much of this colour pattern is evident on regions of the wing not preserved in the single specimen of C. sp. A, which cannot be confidently excluded from this colouration group.

The colour of C. brooksi  is distinctly different from the above, with four dark bands extending from the anterior margin across about 2 / 3 of the wing width to about Cu 2 or 1 A. These are separated by light bands that connect with a light region that extends the length of the posterior portion of the wing. The apical region is preserved as generally light, and may have had complex light colouration in life.

The wing of the Danish C. bittaciformis  has a complex series of light and dark bands and spots ( Willmann 1977: Figs. 1–2View FIGURE 1View FIGURE 2); the undescribed German species figured by Ansorge (2003: Fig 4View FIGURE 4. A, B G) has a dark wing densely covered with small light spots.