SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10585e56318648da62e0bfdbf9c7520203e71670688253f86c6a0c8660b83c00' 
  AND token = 'hMednSLrHTxBQnbhLCm18ebZUSdpOnt1w6BXG3kTQNk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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