SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '4f0abaa4719abc8e900cdc532a41b5e102c9c861ea50c1b687338baeb966c852' 
  AND token = 'Qy8X+JRkZpUvCbcyB3WtrTZIbGiMA7WihslDSFU1DwA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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