SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c3722a2dd2a6a81fe75bedf1e9a6f3703f129f391752aced4839c8087974ddb' 
  AND token = 'WxsJP34GXZhlBcLRddEORLIungi4fQ0L9M8CeZieLNQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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