SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30c03dfaed39aca9557aa03f22e289a73c7dd0a795fb991882395378a14aa622' 
  AND token = 'wr1akO4FoZgTvflZ300QNdVzV1YSzMZ2oKv9aHT4LtA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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