SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'fa7c60fd201e479448d7f48841681a314b412f15d8f29d631d11c29ad499e21b' 
  AND token = 'eOTuUwsIyODURSnVUZhe/CpnkQhTj0D9sv2wIdlJ25Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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