Mastigopsis hjorti (Chun 1913)

Mastigoteuthis hjorti Chun, 1913

Mastigoteuthis hjorti has extremely minute, disc-like, closely packed tubercles, each with a central conical papilla or spire, that cover the surface of the mantle, head, and arms (Figures 57,58). The tubercles on a specimen of 93 mm ML measure 0.1–0.2 mm in diameter and 0.05–0.1 mm high. These tubercles and the epidermal layer in which they are embedded frequently are lost during capture. The tubercles (Figures 60, 61) consist of a relatively densely-staining tubercles have round, triangular, or rectangular bases from which arise 2, 3, 4, or 5 projections (Figures 62–64) which in turn have 2–5 sharp to bluntly rounded cone-shaped papillae at the tip of each projection (Dilly and Nixon, 1976, pl. la). From a specimen of 94 mm ML the 4-armed tubercles, which resemble Maltese crosses, and the 5-armed tubercles are the largest with a diameter of about 0.5 mm and a height of 0.4 mm. The 2-armed tubercles are about 0.8 mm in diameter and 0.2 mm high, while the 3-armed tubercles are about 0.4 mm in diameter and 0.3 mm high.

Kandy District: Hasalaka, Thawalamtenne, and Kandy, Udawattakele Sanctuary

Colombo District: Labugama Reservoir and Mirigama Scout Camp

Ratnapura District: Weddagala, Gilimale, and Belihul Oya

Badulla District: Ella

Monaragala District: Angunakolapelessa

Galle District: Kanneliya

Matara District: Deniyaya

NESTING BEHAVIOR.—I observed this only once in Udawattakele Sanctuary, at 1512 on 22 September 1980. The wasp, 22 mm long, was finishing the closure of her nest, which was placed on a slight slope in dense jungle against a tree root. She tugged at several large leaves, apparently trying to obtain small fragments to conceal the nest entrance. I captured her in a few minutes, and found that her nest was in the tunnel of the prey spider. The tunnel extended 6.4 cm from the entrance to the terminal cell of the spider. The wasp had filled the tunnel loosely with soil. The cell was 2.5 cm long, 2.0 cm high, and 1.5 cm wide. The bulky spider, 21.5 mm long, was thoroughly paralyzed and had been placed on its back with the cephalothorax toward the inner end of the cell. The slightly curved egg, 2.9 mm long and 0.9 mm in diameter, was placed transversely toward the anterior end of the abdominal venter of the spider.

P.B. Karunaratne told me that this spider constructs its nest near the soil surface, lines the tunnel and terminal cell with silk, and makes a funnel-shaped entrance that is camouflaged with pieces of leaf or bark. The wasp must have removed the silk lining the entrance and tunnel before making the closure, for I found a silken lining only at the inner end of the cell.

PREY.—The prey specimens that we collected with the wasps were large, bulky, typical tarantulas belonging to the families Idiopidae and Barychelidae.

The prey at Udawattakele was an adult female idiopid, possibly a species of Scalidognathus Karsch. The other three prey specimens, two from Angunakolapelessa and one from Induruwa Jungle, Gilimale, were immatures of the barychelid spider, Plagiobothrus semilunaris Karsch. I kept one of the prey from Angunakolapelessa alive for some hours. In 6½ hours it recovered enough from thorough paralysis, so that it could flex its legs but was incapable of walking.

PREY TRANSPORT.—I saw a small convexa, 14 mm long, crawling rapidly and excitedly over an almost vertical bank of a dry streambed at Angunakolapelessa at 0943, 27 March 1981. After about five minutes she visited her thorougly paralyzed prey, 13.5 mm long, that was lying venter up on a small flat ledge near the top of the bank. The wasp then disappeared in the leaf litter next to the bank, and returned at 0954. She started to drag off the prey, was frightened by my proximity, and I captured her when she returned 10 minutes later.

At 1415 on this same date T. Wijesinhe saw a small convexa, 12 mm long, walking on the leaf litter in the same dry streambed. She pulled a paralyzed spider, 15.5 mm long, from beneath the leaves, turned it venter down, and, walking backward, dragged the prey while grasping it at the head end.

My last prey record was in the Induruwa Jungle, Gilimale, at 1240, 16 April 1981. A female convexa, 22 mm long, was dragging her thoroughly paralyzed spider, 16.5 mm long, venter up, at the edge of a trail through the dense rain forest.

Williams (1956) noted that the egg of H. ustulata ochroptera was 4.25 mm long, slightly curved, and was attached at one side of the ventral line and at midlength of the spider's abdomen. He also stated that the cocoon was 35 mm long, and was spun of brown silk with a single wall that was varnished on the inner surface.

Hemipepsis indiana Wahis

This rather uncommon species occurs in Sri Lanka and southern India (Bengal, Tranquebar in Tamil Nadu, and Coimbatore in Kerala). Within Sri Lanka it has been collected only in the Dry Zone at altitudes from near sea level to 30 m and with an average annual rainfall ranging from 920 to 1000 mm. Our few records of its occurence in Sri Lanka are as follows.

Mannar District: 0.8 km NE of Kokmotte Bungalow, Wilpattu National Park

Anuradhapura District: Padaviya

Hambantota District: Palatupana Tank

PREY HUNTING.—I saw one female, 20 mm long, hunting for a prey in the leaf litter beneath a small malith tree, Woodfordia fruticosa (Lythraceae) in an open field at Palatupana Tank at 0810, 28 September 1977. During her search she flicked her wings rapidly from a position of being folded flat over her abdomen, and antennated the ground incessantly. She paused briefly at a silken burrow entrance, 10 mm in diameter, next to a tree root, antennated the entrance, and then moved on. She returned 10 minutes later and entered the burrow. A minute later I saw a large spider run rapidly down a slight slope from a second entrance on the other side of the root. The wasp lost sight of the spider scurrying away, but picked up its trail five minutes later. I captured the wasp at 0838, after she had clearly lost the spider's trail.

Dipogon kandiensis (Turner)

This species is endemic to Sri Lanka where we collected it in the Wet Zone at altitudes of 610–1050 m with an average annual rainfall of 3000 mm as follows.

Kandy District: Thawalamtenne and Kandy, Udawattakele Sanctuary

Both of my behavioral records are from Udawattakele, the area in which Turner's holotype specimen was probably captured by O.S. Wickwar.

NEST.—I found a female, 8.7 mm long, sealing the nest entrance in a cavity in a standing dead tree in mid-morning, 22 March 1981. Her abdomen was curved beneath her, and she was using the tip to compact the debris that formed the closing plug. The nest was in an abandoned boring, presumably of a beetle, in sound dead wood with an entrance diameter of about 7 mm. The plug, which came to within 3 mm of the surface when I captured the wasp, consisted of small bits of bark and Singapore, Sarawak, Sumatra, Java, and possibly Sulawesi. Within Sri Lanka it occurs in all three ecological zones at localities with an altitude from near sea level to 610 m and an average annual rainfall of 1000–5000 mm. We collected it in Sri Lanka as follows.

The histological structure of the tubercles resembles vertebrate hyaline cartilage in appearance under light microscopy (Figures 66, 67). The tubercles contain many single and double-chambered chondrocytes suspended in a homogeneous matrix. A dimly visible reticulation of fine dark lines or fibers is disbursed throughout the matrix and may be comparable with the fibers in vertebrate hyaline cartilage. The growing site is at the tips of the papillae where the chondrocytes are new cells that are flat, elongate, and densely packed, versus the single, round chondrocytes, widely distributed through the matrix of the tubercle. The epidermis adheres to the tip of the tubercle.

The mantle tissue (Figure 66) consists of the following histological layers: the epidermal layer, a wide, subepidermal connective tissue layer of chambers that occupy the same level with the tubercles; a dense layer of circular muscle from which the bases of the tubercles arise; a thick layer of longitudinal muscle interwoven with a very thick layer of radial muscle; and a relatively thin layer of circular muscle immediately adjacent to the large-celled, epithelial lining of the mantle cavity.

Idioteuthis hjorti is a species of whip-lash squid.