Crosniera Kensley & Heard , 1991

Poore, Gary C. B., 2015, Rediagnosis of Callianideidae and its genera (Crustacea: Decapoda: Axiidea), and description of a new species of Heardaxius Sakai, 2011, Zootaxa 3995 (1), pp. 229-240 : 232-233

Crosniera Kensley & Heard, 1991

Crosniera Kensley & Heard, 1991 : 500, 501.— Poore 1994: 104 (key).— Poore 1997: 399 –400.— Sakai 2011: 527.

Type species. Callianassa minima Rathbun, 1901 (by original designation).

Diagnosis. Gonochoristic. Rostrum spine-like or acutely triangular. Linea thalassinica incomplete. Thoracic sternite 7 with narrow anterior part, slightly separating cushion-like coxae of pereopods 4. Pleomere 1 tergite with anterior part flat, narrower than posterior part. Eyestalks flattened, contiguous, each with acute apex; pigmented cornea dorsal. Antennal scaphocerite minute and articulating. Maxilliped 3 exopod reaching at least as far as end of ischium, with toothed crista dentata, ischium and merus without brush of stiff non-tapering setae. Pereopods 1 dissimilar, minor cheliped with longer fingers. Pereopod 3 propodus about twice as long as broad, with distal spiniform seta. Pereopod 4 propodus without distal spiniform seta. Pereopod 5 chelate or subchelate, fixed finger with distal spiniform setae. Setal-rows usually on anterolateral carapace, pleomere 1, sometimes pleomeres 2–5, and pleomere 6 (2 rows). Male pleopod 1 2-articled, with distal triangular appendix interna, or a simple single article. Pleopod 2 of male with elongate appendix masculina with long terminal setae, appendix interna digitiform, attached mesially or fused. Pleopods 2–5 rami without marginal filaments. Uropodal endopod without transverse row of short spiniform setae; exopod ovate, without dorsal plate.

Included species. Crosniera corindon Poore, 1997 ; C. dayrati Ngoc-Ho, 2005; C. minima ( Rathbun, 1901) (ex Callianassa ); C. panie Poore, 1997 ; C. wennerae Heard & King, 2007 [plus two species tentatively included and briefly described but unnamed by Poore (1997)].

Remarks. Crosniera differs from all other callianideids in the possession of an acute, usually spike-like rostrum; it shares a long maxilliped 3 exopod with Callianidea . Heard & King (2007) provided a key to all species and discussed their biogeography. Sakai (2011) reiterated much already published but omitted C. wennerae ; his diagnosis is erroneous. My description and figures of pleopods 1 and 2 of C. corindon ( Poore 1997: figs 29G, H) are clearly of a female not of a male as Sakai (2011) suggested (cf. figs of male pleopods, Poore 1997: figs 29M– O).

Crosniera remains problematic. In C. minima and C. sp. 1 of Poore (1997) the male pleopod 1 is 2-articled, the distal article (appendix interna) is triangular (axiid-like as in Paracallianidea laevicauda ) and on pleopod 2 the appendix interna is elongate and attached laterally to the elongate appendix masculina. In C. panie the male pleopod 1 is a simple article (no appendix interna or hooks apparent) and the appendices interna and masculina of pleopod 2 are fused. Males of the others are not known so a revision is premature. No new material of Crosniera was available for this study.