Magnogobius costaricensis, Schwarzhans & Aguilera, 2024

Magnogobius costaricensis n. sp.

Figure 26a–g View Fig

Holotype NMB P15624 View Materials ( Fig. 26a View Fig ), Piacenzian , Río Banano FM, Atlantic Costa Rica, PPP 1732 .

Paratypes 7 specimens: 5 specimens Piacenzian, Río Banano FM , Atlantic Costa Rica ; 1 specimen PPP 676 ( NMB P15629 View Materials ) ; 4 specimens same data as holotype ( NMB P15625-28 View Materials ) . 1 specimen late Zanclean, upper Cayo Agua FM , Atlantic Panama, PPP 1188 ( NMB P15630 View Materials ). 1

specimen Tortonian, Yaviza FM, Pacific Panama, Darien, PPP 1609 (NMB P15631).

Referred specimen 6 specimens: 1 specimen Tortonian, Yaviza FM , Pacific Panama, Darien, PPP 1609 . 1 specimen Zanclean, upper Cayo Agua FM , Atlantic Panama, PPP 1188 . 5 specimens Piacenzian : 4 specimens Río Banano FM , Atlantic Costa Rica, PPP 1732 .

Etymology Referring to Costa Rica where the holotype was found.

Diagnosis Otolith size up to 2.25 mm in length. OL:OH = 0.9–0.97. Otolith shape high-bodied; dorsal rim irregularly curved, with pronounced postdorsal angle and slight postdorsal projection; predorsal angle slightly projecting. Inner face slightly convex. Sulcus long, moderately wide, with distinct ostial lobe and deepened cauda; OL:SuL = 1.35–1.5; sulcus inclination angle 12–17°. Subcaudal iugum long, narrow. Dorsal depression small, oval, only above central part of sulcus.

Description Otolith size up to 2.25 mm in length (holotype). OH:OT = 3.0–3.3. Otolith shape high-bodied with irregularly curved dorsal rim highest at its postdorsal angle. Predorsal angle rounded, often slightly projecting; postdorsal projection blunt or rounded, slightly projecting. Anterior and posterior rims vertical to slightly inclined towards ventral; posterior rim with or without shallow central concavity. Ventral rim straight to slightly bent, horizontal. Preventral angle recessed, postventral angle rounded. All rims smooth except dorsal rim often irregularly undulating.

Inner face slightly convex, particularly in horizontal direction. Sulcus long, moderately wide, with distinct ostial lobe; cauda straight, with rounded tip, slightly upward bent and slightly deepened; sulcus inclination angle 12–17°; OL:SuL = 1.35–1.5. Subcaudal iugum long, narrow, distinct. Dorsal depression small, oval, only above central part of sulcus. Ventral furrow distinct, moderately close to ventral rim of otolith, anteriorly terminating at tip of ostium. Outer face evenly convex, relatively smooth.

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Fig. 26 a–g View Fig Magnogobius costaricensis n. gen., n. sp.; a holotype, NMB P15624 View Materials , Río Banano FM , Limón, Costa Rica, PPP 1732 ; b–g paratypes; b Río Banano FM , Limón, Costa Rica, PPP 676 , NMB P15629 View Materials ; c, f, g Río Banano FM , Limón, Costa Rica, PPP 1732 , NMB P15625-28 View Materials ; d Cayo Agua FM , Bocas del Toro, Panama, PPP 1188 , NMB P15630 View Materials ; e Yaviza FM , Darien, Panama, PPP 1609 , NMB P15631 View Materials . h–o Magnogobius grandis n. gen., n. sp.; h holotype, NMB P386 View Materials , Cercado FM , Dominican Republic, NMB 16915 View Materials ; i–o paratypes; i, l Cercado FM , Dominican Republic, NMB 16918 View Materials , i NMB P386 View Materials , l NMB P15632 View Materials ; j Cayo Agua FM , Bocas del Toro, Panama, PPP 2222 , NMB P15633 View Materials ; k Cercado FM , Dominican Republic, NMB 16916 View Materials , NMB P403 View Materials ; m Río Banano FM , Limón, Costa Rica, PPP 1732 , NMB P15636 View Materials ; n Cayo Agua FM , Bocas del Toro, Panama, PPP 1188 , NMB P15637 View Materials ; o Tuira FM , Darien, Panama, PPP 1163 , NMB P15638 View Materials

Discussion Magnogobius costaricensis does not grow to the large sizes observed in M. grandis n. sp. and further differs in the narrower sulcus, the less strongly developed ostial lobe and the oval dorsal depression. Both species occur parallel in space and time.