SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2bb6fe480af4b2b73bc2bd1ef3b7610b24232259f969fdc45dffd40ae8d58dda' 
  AND token = 'QdhFzZh/lJvbHFMGuHfccLC+ofxgizWszlz7Mepv/6U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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