Sicyonella, BORRADAILE, 1910

Vereshchaka, Alexander L., Lunina, Anastasia A. & Olesen, Jørgen, 2016, Phylogeny and classification of the shrimp genera Acetes, Peisos, and Sicyonella (Sergestidae: Crustacea: Decapoda), Zoological Journal of the Linnean Society 177 (2), pp. 353-377 : 357-358

SICYONELLA BORRADAILE, 1910

Diagnosis: Carapace and abdomen smooth, firm; labrum not much separated from antennae and eyes; rostrum acute with oblique frontal margin and two dorsal teeth; supraorbital, pterygostomial, and hepatic teeth present; sixth abdominal somite and telson in males without ventral processes; telson with four pairs of lateral spines; eyestalks not elongated, cornea well pigmented; third antennular segment without ventral processes, shorter than first segment; stylocerite present, mobile; mandible with palp; maxillula in adults with two endites; first maxilliped with three-segmented exopod and epipod; second maxilliped with epipod; third maxilliped> two times as long as first pereopod, not dimorphic sexually, dactyl four-segmented; first pereopod with ischium lacking strong movable spines and normally developed chela, fingers subequal; second pereopod with merus lacking proximal protrusion and reduced chela lacking elongated setae, fingers subequal; third pereopod with reduced chela lacking strong curved spines and elongated setae, fingers subequal; pereopods IV–V progressively decreasing in length, flat, seven-segmented, carpi and meri setose only on one margin; uropodal exopod setose at distal part 1/5 of outer margin, with small tooth by far not reaching distal end of exopod. Male clasping organ: well developed, without clasping tubercle, bearing two contiguous rows of strong sensory setae or numerous scales. Petasma: pars astringens present, pars media developed, armed with pincers; processus uncifer developed, laminar, lacking hook. Photophores: dermal organs and organ of Pesta absent. Branchiae: podobranch on somite VIII, dendritic anterior arthrobranchs on somites IX–XIII, rudimentary posterior arthrobranchs on somites IX–XII, and dendritic posterior arthrobranchs on somite XIII.

Type species: By monotypy, Sicyonella maldivensis Borradaile, 1910 .

Species: Sicyonella antennata Hansen, 1919 , Sicyonella inermis ( Paul’son, 1875), Sicyonella maldivensis Borradaile, 1910 .

Remarks: Paul’son (1875) described a new species Aphareus inermis from the Red Sea in Russian and referred it to the family Penaeidae . Later Borradaile (1910) established a new genus Sicyonella for a new species, S. maldivensis , and, being ignorant of the Russian paper by Paul’son, was unaware that Sicyonella was identical to Aphareus Paul’son, 1875. Borradaile (1910) established a new subfamily Sicyoninae of the family Penaeidae . Calman (1913) discovered that the generic name Aphareus had been preoccupied by Cuvier (1830) for a fish and so proposed a new name Aphareocaris , also being unaware that this genus was identical to Sicyonella Borradaile, 1910 . Hansen (1919) synonymized Aphareocaris with Sicyonella and described the latest valid species, S. antennata .

The excellent redescription of all valid species of Sicyonella by Fukuoka et al. (2005) with the use of SEM makes morphological comments redundant. Here we present a key to species as one was not provided in Fukuoka et al. (2005). Citations to illustrations that supplement the key are also given.