SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '996eccd2e1a2d5301f2f13c08483864fbfca937eceea4cdd9c4b66cb6ea9aa2d' 
  AND token = 'AcDgw7NTdKFudYkVHae7UZ03s8C0TzyTdRFJ5hYnirU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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