SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'f31a689d09df99ff5bdbe40332d844f222e02a23b73269842c7e764e2df9756e' 
  AND token = 'T9XzzjY6VFBHA+kgXIsYzoV11pRjK8tsCM5KG44lwCw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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