Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '5a55009ab816968d562b11032333b163bc6b16837386b944b2fc6ac17bdb03b9' 
  AND token = 'IFismDloHZAVv18gaWYY0qcnQAL7Nj0ZsTMahH2iqnE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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