Stenothoe bartholomea, Krapp-Schickel, Traudl & Vader, Wim, 2015

Krapp-Schickel, Traudl & Vader, Wim, 2015, Stenothoids living with or on other animals (Crustacea, Amphipoda), Zoosystematics and Evolution 91 (2), pp. 215-246 : 215

Taxon classification Animalia Amphipoda Stenothoidae

Stenothoe bartholomea sp. n. Figures 1, 2, 3, 4, 5

Stenothoe bartholomea Vader 1983: 146 sub Stenothoe n.sp.

Holotype.

female ov. 3 mm, Florida, Monroe County, Cross Key: from Bartholomea annulata (Lesueur, 1817), 4/10/1971, J. Thomas coll. Slide MVRCr 7716, 7717.

Additional material.

one female front part, slide MVRCr 7718; several hundreds, same locality, same date, in alcohol, deposited at MVRCr.

Type locality.

Florida, Monroe County, Cross Key.

Etymology.

after the host anemone Bartholomea annulata (Lesueur, 1817), from where it was collected.

Diagnosis.

Sexual dimorphism lacking. Gn 1 and Gn 2 propodus similar in shape, propodus hind margin rounded, in Gn 2 without clear palmar corner. P 6, 7 basis posterodistal corner lengthened and rounded; merus posterodistally widened and lengthened, reaching half length of carpus. U3 peduncle <ramus. T with or without submarginal spines and marginal setae.

Description.

Length 2.5 - 3 mm.

Head. Eyes round, medium. Mouthparts: Md with acute hook on the place where a palp would have inserted; molar absent, incisor and lacinia mobilis strong, spine row present. Mx 1 palp with 2 arts, Mx 2 plates sitting upon each other. Mxp IP small, OP vanishing. Antennae: subequal, A1 flagellum about 15 arts, A2 flagellum about 10 arts.

Peraeon. Gn 1 basis about 3 times as long as wide, merus triangular, distally rounded and beset with spines, nearly reaching end of carpus; carpus triangular; propodus somewhat wider and clearly longer than carpus, anteriorly beset with long setae; palm well defined by a group of spines and palmar corner. Cx 2 tongue-shaped, posteriorly excavate. Gn 2 basis 3 -3.5 times longer than wide, rectangular; merus rectangular-trapezium-shaped, distally pointed, carpus triangular, distally with stiff short and long pectinate setae, propodus oval, posterior margin regularly rounded, palm defined by some robust spines but palmar corner lacking, with one or more small triangular elevations.

Peraeopods: Cx 3 rectangular, distal margin not much longer than proximal one. Cx 4 triangular, clearly wider than long. P 3, 4 similar, slender, dactylus longer than half propodus. P 5 basis rectolinear. P 6, 7 basis with posterior margin rounded, postero-distal lobe well developed; merus lengthened and widened, reaching about half length of carpus; propodus> carpus, dactylus> half of propodus.

Pleon. U 1 peduncle> subequal rami, all beset with a few spines. U 2 peduncle> longer than unequal rami; U 3 peduncle about 3 times as long as wide, peduncle <ramus, ramus art 1 <art 2, with few short spines.

Telson with or without pair of submarginal spines and small marginal setae.

Remarks.

In Krapp-Schickel 2015 a key is offered for Stenothoe species world-wide, grouped after geographical regions. Among these species this new one is one of only two with a regularly rounded Gn 2 male propodus, lacking excavations, deep incisions or prominent elevations. The other one is Stenothoe tergestina (Nebeski, 1881), frequently found in the Mediterranean, free-living in algae.

Distribution.

Florida, Atlantic Ocean.

Ecology.

living with and on the sea-anemone Bartholomea annulata (Lesueur, 1817).