Family Lepechinellidae Schellenberg, 1926
The amphipod Lepechinella chrysotheras, described by Stebbing (1908), was initially placed in the family Paramphithoidae Stebbing, 1906 . Unaware of this, Chevreux (1914) described Dorbanella echinata and placed it in the family Tironidae Stebbing, 1906 . Schellenberg (1925) described Dorbanella sp. and the family Dorbanellidae . One year later Schellenberg (1926) became aware of the earlier description of a Lepechinella species by Stebbing, and established the family name Lepechinellidae . Later J.L. Barnard (1973) transferred the genera Lepechinella and Paralepechinella Pirlot, 1933 to the family Dexaminidae Leach, 1814 . Barnard & Karaman (1991) included Lepechinella Stebbing, 1908, Lepechinellopsis Ledoyer, 1982, Lepechinelloides Thurston, 1980 and Paralepechinella Pirlot, 1933 in the family Dexaminidae . Andres & Brandt (2001) revalidated the status of family Lepechinellidae . Sittrop & Serejo (2009) gave a more extensive historical review of lepechinellid systematics.
Diagnosis
Andres & Brandt’s diagnosis of Lepechinellidae from 2001 is based on the publications of Schellenberg (1926), J.L. Barnard (1970, 1973) and Bousfield & Kendall (1994): “Diagnosis: Body processiferous dorsomedially (variable), and/or covered with setae/spines. One to all coxal plates of peraeopods 1–4 acutely pointed distally, sometimes bifid. Ursomites 2 and 3 separate to completely fused. Accessory flagellum one- or two-articulate. Mandibular molar and palp present. Lower lip with inner lobes. Maxilla 2: inner plate without oblique row of setae. Peraeopods slender, elongate; peraeopods 5–7 similar, bases linear. Oostegites narrow. Rami of uropods styloid; uropod 3 outer ramus with tiny article 2. Telson normally excavate, lobes usually gaping widely.”
Variations
Rostrum present (e.g., Lepechinella) or lacking (e.g., Lepechinelloides); cephalic teeth present (e.g., Lepechinella) or lacking ( Lepechinelloides, Paralepechinella); urosome segments 2 and 3 separate ( Lepechinella wolffi) to completely fused (e.g., Lepechinella echinata, L. drygalskii and L. curvispina, Paralepichinella spp.); mandibular molar triturative ( Lepechinella, Paralepechinella) or non-triturative ( Lepechinelloides, Lepechinellopsis); mandibular palp three-articulate ( Lepechinella, Lepechinellopsis, Paralepechinella) or one-articulate ( Lepechinelloides); uropods 1–3 outer rami reduced ( Lepechinellopsis); telson cleft distally ( Paralepechinella longipalpa Pirlot, 1933).
Type genus
Lepechinella Stebbing, 1908
The genera included in Lepechinellidae are: Lepechinella Stebbing, 1908; Paralepechinella Pirlot, 1933; Lepechinelloides Thurston, 1980a; Lepechinellopsis Ledoyer, 1982 . This paper also includes a new genus called Lepesubchela gen. nov. The type species of this genus is among others characterized by strongly subchelate peraeopods 6 and 7.
Key to the genera of Lepechinellidae
1. Mandible palp 1-articulate ………………………………………… Lepechinelloides Thurston, 1980
– Mandible palp 3-articulate …………………………………………………………………………2
2. Peraeopods 6 and 7 clearly subchelate …………………………………… Lepesubchela (gen. nov.)
– Peraeopods 6 and 7 simple …………………………………………………………………………3
3. Mandible palp with article 3 extremely long, longer than 10x article 2 … Paralepechinella Pirlot, 1933
– Mandible palp with article 3 normal, shorter than article 2 …………………………………………4
4. Uropods 1–3 with outer ramus strongly reduced, shorter than 1/3 of inner ramus ………………… ……………………………………………………………………… Lepechinellopsis Ledoyer, 1982
– Uropods 1–3 with outer ramus normal ………………………………… Lepechinella Stebbing, 1908