Buea nlonako Mvogo Ndongo, von Rintelen

Buea nlonako Mvogo Ndongo, von Rintelen View in CoL & Cumberlidge n. sp.

( Figs. 2E, F View Figure 2 , 3G, H View Figure 3 , 4E View Figure 4 , 5C, G, K View Figure 5 , 6E, F, J View Figure 6 , 7G–I View Figure 7 , 8C, G View Figure 8 )

Type material: Holotype adult male (CW 25.80 mm, CL 17.80 mm, CH 10.55 mm, FW 7.41 mm), Cameroon, Littoral region, Mt. Nlonako Ecological Reserve (04°54 ʹ 14.7 ʺ N, 09°58 ʹ 16.4 ʺ E), 1,500 m asl, 25 May 2018, coll. P. A. Mvogo Ndongo (ZMB Crust. 31786).

Paratypes: 3 adult males (CW 22.17 mm, CL 15.93 mm, CH 9.09 mm, FW 7.17 mm; CW 22.21 mm, CL 15.82 mm, CH 8.18 mm, FW 6.76 mm; CW 20.91 mm, CL 14.67 mm, CH 7.74 mm, FW 6.29 mm); 2 adult females (CW 30.10 mm, CL 21.78 mm, CH 11.04 mm, FW 8.43 mm; CW 25.12 mm, CL 17.13 mm, CH 9.58 mm, FW 7.17 mm), Littoral region, Mt. Nlonako Ecological Reserve (04°53 ʹ 33.04 ʺ N, 09°59 ʹ 14.0 ʺ E), 900 m asl, 26 May 2018, coll. P. A. Mvogo Ndongo (ZMB Crust. 31787).

Other material examined: 2 adult males (CW 23.31 mm, CL 16.44 mm, CH 8.59 mm, FW 7.60 mm; CW 24.00 mm, CL 17.24 mm, CH 9.30 mm, FW 7.30 mm); 3 adult females (CW 27.47 mm, CL 19.21 mm, CH 10.88 mm, FW 8.24 mm; CW 25.67 mm, CL 18.22 mm, CH 9.80 mm, FW 7.87 mm; CW 26.06 mm, CL 18.56 mm, CH 10.12 mm, FW 7.38 mm); subadult male (CW 16.76 mm, CL 12.60 mm, CH 6.39 mm, FW 5.82 mm), Littoral region, Mt. Nlonako Ecological Reserve (04°53 ʹ 33.4 ʺ N, 09°59 ʹ 14.0 ʺ E), 900 m asl, 26 May 2018, coll. P. A. Mvogo Ndongo (IFAS-012).

Diagnosis: Carapace medium height (CH/FW 1.28, N =12), anterior carapace surface completely smooth; cervical, urogastric, cardiac, branchial grooves distinct, very deep ( Figs. 2E View Figure 2 , 5G View Figure 5 ); postfrontal crest complete, meeting anterolateral margins ( Fig. 5C View Figure 5 ); vertical (pleural) groove on carapace branchiostegite wall faint or absent; carapace branchiostegite lacking vertical (pleural groove) ( Fig. 2F View Figure 2 , 5C View Figure 5 ). Sternal sulcus S2/S3 horizontal, completely crossing sternum ( Figs. 2F View Figure 2 , 5K View Figure 5 ). Major cheliped dactylus stout, relatively straight, lined by small teeth, medium size tooth in middle, pollex of propodus with 3 large teeth proximally, followed by smaller teeth interspersed by 2 distinct teeth ( Fig. 3G View Figure 3 ). Lower margin of cheliped merus lined by pointed teeth, distal tooth largest (sharp spine) ( Figs. 2F View Figure 2 , 6E, F View Figure 6 ). Terminal segment (TS) of mandibular palp bilobed, with small but distinct setae-fringed anterior lobe (0.1× TS length) ( Fig. 8C View Figure 8 ). G1 TA broad, long, but not equal to SS length (TA/SS 0.70) ( Figs. 7G, H View Figure 7 ); G2 TA extremely short (TA/SS 0.18) ( Fig. 7I View Figure 7 ).

Description: Carapace ovoid, medium height (CH/FW 1.28, N = 12), width more than 3× FW (CW/FW 3.31, N = 12); carapace surface smooth, anterior corners of carapace each with

field of carinae; cervical, urogastric, cardiac, branchial grooves distinct, very deep ( Figs. 2E View Figure 2 , 5G View Figure 5 ); postfrontal crest distinct, complete, lateral ends meeting anterolateral margins ( Figs. 2E View Figure 2 , 5C, G View Figure 5 ); exorbital angle low, clearly distinct, intermediate, epibranchial teeth each reduced to small granule ( Fig. 5C View Figure 5 ); anterolateral margin behind epibranchial tooth with small granules ( Fig. 5C View Figure 5 ). Carapace branchiostegite with longitudinal suture dividing wall into 2 regions, lacking vertical (pleural) groove ( Figs. 2F View Figure 2 , 5C View Figure 5 ). Margin of sternum with setae; sternal sulcus S2/S3 horizontal, completely crossing sternum; S3/S4 incomplete, reduced to 2 small side notches ( Figs. 2F View Figure 2 , 5K View Figure 5 ); episternal sulci S4/E4, S5/E5, S6/E6 complete, S7/E7 missing ( Figs. 2F View Figure 2 , 5K View Figure 5 ).

Chelipeds of adult male greatly unequal ( Figs. 2E, F View Figure 2 , 3G, H View Figure 3 ). Fingers slim, elongated; movable finger (dactylus) stout, straight, lined by small teeth, medium size tooth in middle, pollex of propodus with 3 large teeth proximally, followed by smaller teeth interspersed by 2 distinct teeth ( Fig. 3G View Figure 3 ). Minor cheliped dentition similar to major cheliped but smaller, enclosing oval interspace

when closed ( Figs. 3H View Figure 3 ). Cheliped carpus with 2 large, unequal teeth, distal tooth largest, proximal tooth smallest ( Figs. 6J View Figure 6 ). Medial inferior margin of cheliped merus with large distal tooth, lined by small pointed teeth proximally ( Figs. 2F View Figure 2 , 6E, F View Figure 6 ). Walking legs (pereiopods P2–P5) moderate length (not unusually elongated), posterior margins of propodi lined by small pointed teeth, dactyli tapering, each bearing rows of downward-pointing large sharp spines, tip with long spine ( Figs. 2E, F View Figure 2 ).

Mandibular palp 2-segmented, terminal segment (TS) bilobed, with short but distinct setae-fringed anterior lobe (0.1× TS length) ( Fig. 8C View Figure 8 ). Third maxillipeds filling entire buccal cavern, except for transversely oval efferent respiratory openings in superior lateral corners ( Fig. 8G View Figure 8 ); ischium with distinct vertical sulcus; third maxilliped exopod either completely lacking flagellum, or with extremely reduced short process ( Fig. 8G View Figure 8 ).

Male pleon triangular, sides not indented, telson (A7) rounded at distal margin ( Figs. 2F View Figure 2 , 5K View Figure 5 ). G1 TA long (TA/SS 0.70), proximal half straight, robust, distal half directed outward tapering evenly to pointed tip, G1 TA with long setae lining ventral margin ( Figs. 7G, H View Figure 7 ). G2 SS robust at base, tapering to long thin rod, reaching middle of G1 TA. G2 TA extremely short (TA/SS 0.18), slender ( Fig. 7I View Figure 7 ).

Size: A medium-size species, adult size range CW 20.9–30.1 mm.

Color in life: Dorsal carapace and appendages all dark brown; P1, chelipeds dark brown with white fingertips ( Fig. 4E View Figure 4 ).

Type locality: Nlonako Wildlife Reserve, Nkongsamba , Littoral region, Cameroon.

Etymology: The new species is named for the Nlonako Wildlife Reserve. The species epithet is a noun in apposition.

Habitat: Buea nlonako n. sp. is known only from the Nlonako Wildlife Reserve , which includes Mt. Nlonako, which rises from 400 m asl on its southern side to 1,825 m at its peak ( Fig. 4G View Figure 4 ). The reserve lies in the Littoral region of Cameroon, which is one of the most threatened tropical rainforest habitats in this part of Africa.

Nomenclatural statement: A life science identifier (LSID) number was obtained for the new species: urn:lsid:zoobank. org:pub:399269F4-4FA2-4858-ADE0-C281CBF79278.