Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'ab79e2469d637eafe979f1a59dca80c279b241bdafdb9b6bf5392d081c51ac7a' 
  AND token = 'vrdBFsZTrbeZ4cHVNrLTTa3OAwthSwx4EOali6pCG+A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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