SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce213886666e86ec27d6076d52b54eb43c87cd2c4cec2a17bd849cd963ffef8a' 
  AND token = 'h7oZy9dXXC6j0k0v8kdPWNxce0Oxv4OlnncgiATzSkU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}