SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '74ba5e08c8c9c25f17d0abf73081e79154822142a0a3e1bfba5c9fe693c6756b' 
  AND token = 'MclzYQT0ngEde0E0K88Gl7HcEvPiiqAVgiT5VPnbQNQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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