Copidognathus caloglossae, Proches, 2002

Copidognathus caloglossae sp. nov.

( figure 3 View FIG )

Material. ( BMNH(E) 2001-13 ) HOLOTYPE: male, South Africa, Eastern Cape, Mtakatye Estuary , May 1999, leg. S,. Proches, . PARATYPES: one male, two females, and one protonymph, data as in holotype; one protonymph, and two larvae, from South Africa, KwaZulu-Natal, Bayhead Lagoon in the Durban Harbour , July 1999, leg. S,. Proches, . Other material (30 more individuals examined) comes from Richards Bay, Isipingo and Beachwood mangrove forests in KwaZulu-Natal, as well as from Inhambane ( Mozambique) .

All individuals were collected from the algal association known as`Bostrychietum', covering the pneumatophore s of the mangrove-tree Avicennia marina (Forsk.) Vierh.

Male. Idiosoma 370-425 μm long and 275-300 μm wide.

Dorsum. AD 115- 135 μm long and 140-150 μm wide, with ds- 1 in the anterior half. Three prominent porose areolae present, one oblong, anterior and two rounded, centro-lateral, all with groups of 5-10 pores. Other pores are present on all edges of the plate, without forming clearly de fi ned fi elds. OC 90 -125 μm long and 60-80 μm wide, with centro-lateral porose areolae, one seta and two corneae. A ridge separates the postero-lateral end of OC by from the rest of the plate. PD 230-260 μm long and 220- 230 μm wide, with four large costae covered with groups of 10-15 pores; the space between the costae with an indistinct canalicular reticulation ( figure 3A View FIG ).

Venter. AE 120- 155 μm long and 240-260 μm wide, with the fi rst three pairs of ventral setae. Canaliculi mainly in two transverse bands, joining the origin of legs in pairs I and II, respectively. PE 160-180 μm long, with evenly distributed canaliculi, carrying one dorsal and three ventral setae. GA 175-210 μm long and 150-180 μm wide, with genital opening placed behind the middle. Five to nine pairs of perigenital setae, generally disposed in one circle; sometimes the posterior ones are more outwardly placed than the anterior ones. Genital opening with four pairs of subgenital setae, two anterior and two posterior ( figure 3B View FIG ).

Gnathosoma. Gnathosoma 130-135 μm long and 115-125 μm wide, rostrum slightly shorter than gnathosomal base, palpi longer than rostrum. Gnathosomal base with evenly arranged canaliculi. Distal segment of palpus with a whorl of three long basal setae and a few small terminal setae ( figure 3C View FIG ).

Legs. First pair shorter and more robust than other legs. Claws smooth, no accessory process was identi fi ed ( figure 3I View FIG ). Canaliculi present, especially in the femora and tibiae of legs I and II. Chaetotaxy, trochanter to tibia: leg I, 1, 2, 5, 4, 7; leg II, 1, 2, 4, 4, 7; leg III, 1, 2, 2, 3, 5; leg IV, 0, 2, 2, 3, 5. Medial bipectinated setae on tibiae: two on legs I and II, one on legs III and IV ( figure 3E -H View FIG ). Ventral setae on telofemora I and II, as well as on all basifemora very short ( figure 3J View FIG ). Dorsal setae on tarsus I and II located in the middle of the segment.

Female. Idiosoma 410-450 μm long and 305-335 μm wide.

Dorsum. Similar to the male, AD 115-120 μm long and 155-160 μm wide. OC 105- 120 μm long and 80-105 μm wide. PD 260-335 μm long and 215-230 μm wide.

Venter. AE 160-165 μm long and 270-275 μm wide. PE 170-180 μm long. GA 200- 205 μm long and 150-175 μm wide, with genital opening placed slightly behind the middle. Three pairs of perigenital setae ( figure 3D View FIG ).

Gnathosoma. Gnathosoma 130-160 μm long and 100-130 μm wide.

Protonymph. Idiosoma 275-410 μm long and 225-310 μm wide. Plates smaller than in adults, as compared to total body length, leaving large areas of striated integument. AD 60-75 μm long and 90-95 μm wide. OC 50-60 μm long and 45-50 μm wide, with two corneae located on a protuberance; however, the posterior ridge present in adults is absent. PD 130-145 μm long and 155-195 μm wide. AE 85-95 μm long and 160-220 μm wide. PE 125-130 μm long. Genital and anal plates separate; genital 45-60 μm long and 50-60 μm wide, anal 50 μm long and 75- 80 μm wide.

Gnathosoma. Gnathosoma relatively small, 125-130 μm long and 45-90 μm wide.

Legs. Legs signi fi cantly smaller than in adults, basifemur and telofemur IV merged in one femoral segment.

Larva. Idiosoma 270-280 μm long and 195-210 μm wide; plates small, large parts of the integument are not striated, but have irregular folds. AD 50-55 μm long and 55-60 μm wide. OC 25-30 μm long and 30-35 μm wide. PD 75 -85 μm long and 95- 100 μm wide. AE 75 -85 μm long and 160-170 μm wide, with large, clearly visible pores. PE 65-75 μm long. Genital and anal plates separate; genital 25-30 μm long and 35-40 μm wide, anal 40-45 μm long and 70-75 μm wide.

Gnathosoma. Gnathosoma 105-110 μm long and 40-80 μm wide.

Legs. Femoral segments merged in all legs.

Etymology. The name caloglossae refers to the alga Caloglossa leprieurii (Mont.) J. Ag. , one of the components of the algal association from which the mites were collected.

Remarks. One uncommon feature found in C. caloglossae sp. nov. is represented by the completely smooth claws. It has been suggested that in the halacarid subfamily Rhombognathinae , smooth claws are associated with species from habitats exposed to little wave action, while claw combs are used for securing the mite to substrata exposed to strong wave action ( Pugh et al., 1987). As southern African mangroves are an estuarine feature, the wave action is low, favouring similar features in C. caloglossae sp. nov. (subfamily Copidognathinae ). Other characters which, combined, are useful in de fi ning this species are the four dorsal costae covered with groups of pores, short mouthparts, the short ventral setae on telofemora I and II, as well as on all basifemora, the medial position of dorsal setae on tarsi I and II.

An aspect worth noting is the presence of this species in the Isipingo Estuary, where salinity is close to zero. Five other species of Copidognathus have been recorded from similar low-salinity habitats ( Bartsch, 1996).