SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'ed917ae4c4d8004320073817b0286f98fc2a6cce2476d02ef5b17152d4cd7c97' 
  AND token = '9DH6VjZZbjU+lmnquRNtEUhBaknWCO848q9Jg0vx1lE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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