SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'daab3e136dcd0d532d23ac242758191e3d7c33532e90bf52c4834a2264a55ddf' 
  AND token = 'vcyPZmGJJACkGlYNZgoHGiY+yE/vPLEpuVT9Wxpvmrw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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