Genus Iulopis Bovallius, 1887

Iulopis Bovallius, 1887: 17 . – Barnard 1930: 418. Hurley 1955: 144. Bowman & Gruner 1973: 33. Vinogradov et al. 1982: 339. Vinogradov 1999a: 1186.

Euiulopis Bovallius, 1889: 116–117 .

Euiulopsis – Pirlot 1929: 120.

Type species

Iulopis loveni Bovallius, 1887, designated by Bowman and Gruner (1973). Type material could not be found at the SMNH, ZMUC or in Uppsala and is considered lost (but see later). However, Iulopis is a readily recognisable genus.

Diagnosis

The characters of the family are also those of the genus.

Two species.

Sexual dimorphism

As with most hyperiideans, the morphology of the antennae is the most useful means to differentiate the sexes. The antennae of males are multi­articulate, filiform, and much longer than the head and pereon, whereas in females the first antennae are much shorter than the head, and consist of only four articles, while the second antennae are absent in one species but three­articulate in the other species.

Females also have a broader pereon, the uropods are relatively more slender with relatively longer rami and the telson is also relatively longer.

Remarks

Iulopis is a very distinctive genus. It is rarely found in plankton collections and consequently very little is known about the biology of species.

In the general structure of the gnathopods it occupies an intermediate position between Hyperia and Hyperoche .

Key to the species of the genus Iulopis

1. Gnathopod 1 weakly chelate, carpal process forming small, triangular lobe. Gnathopod 2 with slender carpal process, almost as long as propodus. Gnathopods 1 & 2; carpal process with single, robust seta terminally ......................... I. loveni Bovallius, 1887

­ Gnathopod 1 subchelate, carpal process rounded, not produced. Gnathopod 2 with triangular carpal process, produced to about middle of propodus. Gnathopods 1 & 2; carpal process with scattered robust setae in addition to short, slender setae ............................................................................................. I. mirabilis Bovallius, 1887