Cryptophyllium yapicum (Cumming & Teemsma, 2018) Cumming & Bank & Bresseel & Constant & Tirant & Dong & Sonet & Bradler, 2021

Cumming, Royce T., Bank, Sarah, Bresseel, Joachim, Constant, Je ́ ro ̂ me, Tirant, Stephane Le, Dong, Zhiwei, Sonet, Gontran & Bradler, Sven, 2021, Cryptophyllium, the hidden leaf insects - descriptions of a new leaf insect genus and thirteen species from the former celebicum species group (Phasmatodea, Phylliidae), ZooKeys 1018, pp. 1-179 : 1

Cryptophyllium yapicum (Cumming & Teemsma, 2018) comb. nov. Figures 73 , 74

Material examined.

(3 ♀♀, 1 ♂): At present only the holotype within the CAS collection, and three additional specimens within the BPBM collection are known to us. 1 ♀: "M.R.Lundgren, Collector. Kaday, Yap, Xi.10.1980. CASTYPE #19438, Holotype" (Fig. 73 ); 1 ♀: "Yap Islands, Yap I., Kolonia. R. P. Owen, Collector. 6-xii-'63, unknown tree. BPBMENT, 0000080399" (Fig. 74A ); 1 ♀: "Yap, 25.XI.1940, H. Fujishima. Micronesia coll., Entomology Lab., Kyushu univ., Fukuoka, Japan. BPBMENT, 0000080401." (Fig. 74C ); 1 ♂: "Yap, S. Ikuta. Micronesia coll., Entomology Lab., Kyushu univ., Fukuoka, Japan. Yap. The specimens was at, first preserved in Formalin, and therefore the coloration, was faded. BPBMENT, 0000080400." (Fig. 74E ).

Remarks.

This species is apparently rather elusive as it is one of the largest insects in Micronesia but also one of the rarest (as it is only known from four museum specimens). This poorly known species is only represented by old/degraded specimens collected between 1940 and 1980 and therefore it is one of only two species excluded from our molecular analysis (the other being Cryptophyllium athanysus comb. nov. only known from antique specimens and recent photographs). Hopefully further collection efforts in Micronesia will locate this species again so it can be observed live, and a tissue sample can be recovered in order to help place the unique species phylogenetically.

Differentiation.

Both sexes have the unique feature of having the interior protibial lobe reduced on the distal half with a majority of the lobe and the widest point on the proximal half only (Fig. 73B ) which allows differentiation from all congenerics.

Females with their boxy rounded abdomen and rounded but broad exterior profemoral lobes are visually similar to Cryptophyllium bollensi sp. nov. and Cryptophyllium westwoodii comb. nov. moderate form females. From both species Cryptophyllium yapicum comb. nov. can be differentiated by the unique protibial interior lobe as the other species have fully spanning lobes with the broadest point on the distal half of the protibiae. Additionally, these species do not have mesopleura with large tubercles (Fig. 73C ), instead they have granular surfaces.

Males are quite unique and do not readily resemble congenerics. With an abdomen that has abdominal segments V and VI parallel-sided, their abdomen is boxy and unlike the typical Cryptophyllium gen. nov. abdomen (which are generally ovoid or spade-shaped). The closest that other Cryptophyllium gen. nov. species get to a boxy abdomen like this is in Cryptophyllium celebicum comb. nov. but in this species typically only segment V is parallel-sided and VI is generally bent and converging on the posterior half. These two species can be differentiated by their significantly differing tegmina lengths as Cryptophyllium celebicum comb. nov. tegmina only reach to the anterior margin of abdominal segment III but Cryptophyllium yapicum comb. nov. have the longest tegmina recorded in this genus. Cryptophyllium yapicum comb. nov. tegmina reach onto abdominal segment V and is therefore a feature which differentiates this species from congenerics as the next longest are recorded in Cryptophyllium oyae comb. nov. and Cryptophyllium yunnanense comb. nov. which only reach to the middle of abdominal segment IV.

Distribution.

Only known from the areas of Colonia and Kaday on Yap Island, Micronesia.

Figures

Figure 73. Holotype female Cryptophyllium yapicum comb. nov. photographed by RTC A habitus, dorsal B ventrolateral view of the protibiae showing the unique lobe shape C details of the thorax and head, dorsal D lateral view of the thorax-head E terminalia, ventral.

Figure 74. Three additional non-type specimens of Cryptophyllium yapicum comb. nov., photographs by Miho Maeda, Jerilynn Chun, and James Boone, 2020 (BPBM). Corresponding data labels below the specimen A female habitus, dorsal B associated data labels C female habitus, dorsal D associated data labels E male habitus, dorsal F associated data labels.