SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2cab9ba94d57153e26259081b5799404d150924696cf87895ba5df5908dd11fb' 
  AND token = 'KmMPDMe8nRHJYTjVZqlVjNdz+3cJQCWk4fImJpXtJ8A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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