SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'aabdbab75fd480c8e6278d447fe973533df78fd55a7bc22840ddb07c758dcc71' 
  AND token = 'OcHXspwhIVDFjNL/Huw/q9CIg+HNTDBzSIjr0hnt6Wg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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