SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '18b055e03c8cb6f642f0aaff26ada7ed4af633d3d6c61caf1e7df9c333bf98c1' 
  AND token = 'iMctv3qX7ykW0JxYAiD5QMhnkZKDOqzUtGvnoiQPckk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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