Mymarilla Westwood

Huber, John T., 2013, Redescription of Mymarilla Westwood, new synonymies under Cremnomymar Ogloblin (Hymenoptera, Mymaridae) and discussion of unusual wings, ZooKeys 345, pp. 47-72 : 47-48

Mymarilla Westwood

Mymar : Westwood 1879: 585 ( Mymarilla wollastoni included, together with another, correctly placed species).

Mymarilla Westwood, 1879: 585 (footnote) + figs 8, 9 (recommended as a new genus group name for Mymarilla wollastoni "if it should be deemed necessary to separate this species from the genus Mymar ").

Mymar : Dalla Torre 1898: 427 ( Mymarilla treated as a synonym).

Mymarilla : Schmiedeknecht 1909: 495 (treated as valid genus with one [incorrectly placed] species but no mention of Mymarilla wollastoni ).

Mymar : Schmiedeknecht 1909: 496 (listed M. Wollastoni [sic] together with three other species [one other of which is also incorrectly placed generically]).

Mymarilla : Ferrière 1952: 43 (treated as valid name for Mymar of authors, not Curtis).

Mymarilla : Doutt 1955: 11 (key), 12 (treated as valid genus, but noted that American authors used Mymar as the name for species included under Mymarilla by previous workers).

Mymarilla : Heqvist 1960, 432 (treated as valid genus with one [incorrectly placed] species but no mention of Mymarilla wollastoni ).

Mymarilla : Annecke and Doutt 1961: 31 (discussion of past confusion with Mymar ).

Type species.

Mymarilla wollastoni Westwood, by monotypy. Transferred (as genotype) to Mymarilla by Heqvist (1960: 432).

The confusion in the use of the name Mymarilla and which species should be placed in the genus continued for over 80 years. Heqvist (1960) was the first to treat Mymarilla wollastoni as the genotype of Mymarilla , even as he incorrectly placed Mymar species under it, as did previous authors. As Annecke and Doutt (1961) clarified, wherever previous authors use Mymarilla it was clearly in the sense of Mymar , because the species names mentioned are typical Mymar species.

Diagnosis.

The combination of smooth, shiny black body, extremely short mesocutum compared to much longer pronotum, and extraordinary convex and densely setose fore wing distinguish the genus and species from any other Mymaridae .

Mymarilla belongs clearly to the Polynema Halidaygroup of genera within Mymarini sensu Annecke and Doutt (1961). They suggested that Mymarilla was most similar to Oncomymar Ogloblin from the Juan Fernández Islands. Superficially, the most similar genus is Cremnomymar Ogloblin (including Oncomymar Ogloblinand Scolopsopteron Ogloblin, see below), some of whose species also have a convex fore wing and reduced mesoscutum. The two genera are not closely related; their resemblance is due to adaptations to life on remote, presumably wind-swept, oceanic islands.

I propose instead that Mymarilla is derived from Stephanodes Enock, likely the most closely related genus. Four features, shared with Stephanodes , suggest this: first, the extremely smooth body without trace of microscupture on the mesosoma (Figs 1, 3, 4, 6, 9, 10); second, the slightly advanced mesothoracic spiracle about midway between the anterior apex of a notaulus and posterolateral angle of the mesoscutum (Figs 3, 4); third, the presence of a metapleural pit (Figs 9, 10); fourth, the fore wings that are held more or less horizontally. In dead specimens of Stephanodes , the fore wings are often horizontal, crossed scissor-like and covering the body, unlike other, related genera in the Polynema -group where the wings (in dead specimens) are almost always vertical, directed away from the body. The strong convexity of the fore wings of Mymarilla would appear to prevent them from being crossed scissor-like over the body. Yet they are presumably capable of enveloping the metasoma, as pointed out by Westwood who noted "... when shut [the fore wings] form a semiglobular dome over the abdomen" when the wasp is at rest. The densely hairy wing membrane with dark base around each microtrichia would allow for maximum heat absorption and retention.