Eulimnadia gnammaphila Timms, 2016

Timms, Brian V. & Rogers, D. Christopher, 2020, Fig. 5 in Paralbunea dayriti, Zoological Studies (Zool. Stud.) 59 (38), pp. 1-10 : 6-7

Eulimnadia gnammaphila Timms, 2016

Comments: Now that E. feriensis is considered a Paralimnadia , if Reed et al. (2015) had correctly identified their specimens, they would have appeared as Paralimnadia and Eulimnadia in their phylogenies, but they sequenced them only as Eulimnadia . The Gene Bank accession numbers in their table 1 for E. dahli and E. feriensis , both misidentified, should be reassigned to E. gnammaphila .

Comments on taxonomy

Besides a strict interpretation of the subcercopodal projection, three other characters may be used in distinguishing between Eulimnadia and Paralimnadia : 1) cercopod setal row terminating with a small spine at or near 75–80% of cercopod length in Eulimnadia and at or near 40–65% in Paralimnadia ; 2) second antenna with entire/unregenerated flagellae with antennomeres numbering ca 8 in Eulimnadia and ca 12 in Paralimnadia , and; 3) the very few or no males to females ratio suggest androdioecy and probably Eulimnadia , while 1:1 ratios indicate gonochory and Paralimnadia . It is possible some Eulimnadia (e.g., E. hansoni ) are gonochoristic ( Timms 2016a) so this character is not absolute, though there are no known Paralimnadia which reproduce androdioeciously.

We have no molecular data to confirm the new generic placements of the species listed above in the results section. However, analyses are in progress. Based on these characters and our associated results, we revise the diagnoses for the two genera.

Eulimnadia Packard, 1874

Diagnosis: (modified from Rogers et al. 2012). Populations composed of males and hermaphrodites or hermaphrodites only; amplexus is transverse (venter to venter). Rostrum variable, blunt to acute, long or short. Angle between rostrum and frons 100° to 80°. Occipital notch and occipital condyle absent. Pedunculate frontal organ length approximately 1.55 x distance of organ from ocular tubercle. Second antenna with ~8 antennomeres per flagellum. Carapace dorsal margin smooth, lacking carinae, hinge line arcuate, rarely sinuate. Carapace intervals smooth. Umbone absent. Carapace occasionally pigmented. Muscle scar angle from 0° to 90° from the longitudinal axis of the animal. Clasper endopods each bearing an apical suctorial organ. Endite IV may be broadly transverse or bear dense apical field of short setae, or a few long setae or spines. Thoracic segments smooth or with dorsoposterior ridge rimmed with spines or setae. Eggs attaching to prolonged exopods of thoracopods VII and VIII or VIII, VIII to IX or XII, IX and X, X and XI, or XI and XII. Telson with posteriorly directed subcercopodal spiniform projection on ventroposterior angle, anteriad of cercopod base. Telson posterior margin posteriolateral spine rows confluent dorsally, with confluence not projecting. Each row has from 6 to 22 spines. Caudal filament originating between spine rows at second, third, fourth, fifth, or seventh spine from confluence. Caudal filament borne on projecting mound. Cercopods arcuate, occasionally sinuate. Cercopod with medial longitudinal setal row on proximal 75–80%. Setae plumose and long. Setal row terminates with single spine. Cercopod with subapical, dorsal cirrus, extending from 5–30% of cercopod length. Eggs 170–250 μm in diameter. Shape spherical to subspherical or cylindrical to subcylindrical with one end larger than other. Eggs with large rectilinear polygonal depressions separated by ridges, occasionally with lamellar or setaform spines at polygon ridge line confluences ( Belk 1989, Martin 1989, Martin and Belk 1989, Rabet 2010). Australian ( Australia), Afrotropical, Nearctic, Neotropical, Oriental, and Palaearctic (North Africa) bioregions.