Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '2a8ba6ea01bf36ee20c75dd4955c4c1a729c91be64e1e0f944ccefd832fcdf66' 
  AND token = 't+qMuFKAfwDSzCsU15JCKcYFKIrmv3IGNDnKSV4sUNA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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