SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'bb1b690cbbb36ba44b294fcbc5bd1df67b6b112db6141c5d49fdfc0c9b6e8261' 
  AND token = 'jr1u5wC+2h/h+Ni2DEzPwfPrVIOx70CwCPLGJbKWs7I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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