Stamnodes cassinoi Swett, 1917

Matson, Tanner A., 2023, A review of Mexican Stamnodes (Lepidoptera: Geometridae) with the description of 16 new species, European Journal of Taxonomy 911, pp. 1-79 : 61-63

Stamnodes cassinoi Swett, 1917

Figs 32 , 94–95

Stamnodes cassinoi Swett, 1917: 52 . Type locality: Eldridge, California, USA. [MCZ].

Stamnodes cassinoi – McDunnough 1938: 151 (checklist). — Peterson 1968: 86–87. — Ferguson 1983: 103 (checklist). — Furniss et al. 1988: 7. — Poole & Gentili 1996: 686 (checklist). — Scoble 1999: 901 (catalogue). — Brown & Bash 2000: 73. — Powell 2005: 369. — Scoble & Hausmann 2007 (online catalogue). — Pohl et al. 2016: 449 (checklist). — Rajaei et al. 2022 (online catalogue).

Diagnostic remarks

Stamnodes cassinoi is not easy to distinguish from S. annellata and S. costimacula . Males can be separated from those of S. costimacula by their filiform and non-bipectinate antennae. Generally, the basal half of the hindwing underside is darker brown than in S. annellata and S. costimacula , and the costal margin at the antemedian often has a noticeable semicircular ochreous patch. Genitalic dissection (Matson & Wagner in prep.) and genetic analysis are sometimes necessary to distinguish this taxon from others.

Distribution

Mexico: Stamnodes cassinoi is found in the chaparral associations, foothills, canyons, and Pacific coastal scrub communities of northwestern Baja California. USA: the core of this species’ range lies in California. Stamnodes cassinoi appears to prefer more coastal habitat than congeners and rarely ranges inland.

Biology

Stamnodes cassinoi feeds on Cercocarpus betuloides in southern California and likely Mexico. There is a single flight, from early December through January, with mature caterpillars following into March. The caterpillar and host plant were discovered by David L. Wagner and the author in March 2016 in southern California. Additional unpublished life history details and larval illustrations are forthcoming (Matson & Wagner in prep.).

Molecular characterization

This species is represented in BOLD as BIN: BOLD:AAF9456 (n = 10). At present, the average pairwise intraspecific distance is 0.59%, the pairwise maximum intraspecific distance is 1.12%, and the distance to the nearest neighbour, Stamnodes modocata (n = 2), is 4.67%.

Figures

Figs31–40.Adult StamnodesGuenée,[1858],dorsal(a)andventral(b)views.31.S.costimacula(Grossbeck, 1912) (DLW). 32. S. cassinoi Swett, 1917 (DLW). 33. S. annellata (Hulst, 1887) (USNMENT01771252). 34. S. seiferti (Neumoegen, 1882) (USNMENT01771250). 35. S. tenebrosa sp. nov., holotype, ♂ (AMNH_IZC 00352924). 36. S. affiliata Pearsall, 1911 (DLW). 37. S. reckseckeri Pearsall, 1910 (USNMENT01771257). 38. S. apollo Cassino, 1920 (USNMENT01771258). 39. S. agapetica (Dyar, 1916) (USNMENT01771259). 40. S. albiapicata Grossbeck, 1910 (USNMENT01771253). Scale bar = 1 cm.

Fig. 94. COI neighbour-joining tree for Mexican Stamnodes Guenée, [1858] using default Kimura-2P model in the Barcode of Life Project (BOLD). Taxon names followed by BOLD Process ID.

Fig. 95. Biogeographic associations of Mexican Stamnodes Guenée, [1858]. (*) denotes species found in two or more provinces. Underlying biogeographic provincial map taken from Morrone (2020: fig. 4.5) with permission to reproduce this figure granted by author Juan J. Morrone.