SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '560115d093bc53d30ff9f547a22b3f7bf77a2ea7fbb0d2055b703b4a6980b2cd' 
  AND token = 'MoOJIPa2RMF0KSZYPmkL8SUAlvrvFYXDpo4UOi8VjJM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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