SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dceccabe1d603e3f8a5edcb1871a5a650ae3d21d60229e83a85d519d735c6a3d' 
  AND token = 'CaLTp4ISyqdHKnRKZDyXTKGnQNipqiDC7YEDEqNbYUw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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