SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '7158143ae6f540eea2ad26068ca7f3869aea5edb2772b0ca7dba2aa799b58889' 
  AND token = 'HPmIpLGjCtSrt3Nwou5N+tOeaxEVBgwGkyKuJLyJlx8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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