Palaemonopsis Stimpson, 1871

Grave, Sammy De & Ashelby, Christopher W., 2013, A re-appraisal of the systematic status of selected genera in Palaemoninae (Crustacea: Decapoda: Palaemonidae), Zootaxa 3734 (3), pp. 331-344 : 340

Comments on Palaemonopsis Stimpson, 1871 and Allocaris Sollaud, 1911

Palaemonopsis was mentioned in Stimpson (1871) under his introduction to the genus Palaemonetes , with the comment that: “…The genus [ Palaemonetes ] was described by me in manuscript about twelve years ago under the name Palaeomonopsis , but this name has never before been published, and I believe it to be identical with Palaemonetes of Heller…”. Stimpson (1871) did not further discuss the name and goes on to list Palaemonetes vulgaris , Palaemonetes carolinus Stimpson, 1871 and Palaemonetes exilipes Stimpson, 1871 ; the latter long since regarded as a junior synonym of Palaemonetes paludosus (Gibbes, 1850) . Holthuis (1955) lists the genus under the synonymy of Palaemonetes and selected a type species by subsequent designation, namely Palaemonopsis carolinus Stimpson, 1871 , which he also considered to be a junior synonym of Palaemon vulgaris Say, 1818 ; up to now included in Palaemonetes . This generic level synonymy is upheld by the results in Ashelby et al. (2102), who recover P. vulgaris deeply embedded within their Palaemon sensu lato clade.

Allocaris was erected as a new genus by Sollaud (1911), with Allocaris sinensis Sollaud, 1911 as its type species, by monotypy. The genus was considered distinct from Palaemonetes on the basis of the wide separation of the coxal and basal segments of the first maxilliped, as well as the more numerous apical telson setae. Pesta (1913) discusses the invalidity of these differences and placed Allocaris into the synonymy of Palaemonetes , treating Sollaud’s (1911) species as Palaemonetes varians var. loci sinensis . Although Kemp (1918) agreed with the generic synonymy, he disagreed with Pesta’s view to consider A. sinensis as a local race, affording full species status to Palaemonetes sinensis ( Sollaud, 1911) . Since then, this generic level synonymy has been accepted (see Bruce 1994) and is upheld by the results in Ashelby et al. (2102), who recover P. sinensis deeply embedded within their Palaemon sensu lato clade.