SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7bf5cc359581e6e224fbce17280129b2b62de5b6c715cb7f7d508abc8e3fa685' 
  AND token = 'wYuIqKG+w28hHpOjJYhgj9HMmke/hZ1lYY2M5kfjUD4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

JSON explain

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