SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6dccf29ac91c9c5f7862ddf4bfe7d9a54d9e671a1a0fe144e72131445579db70' 
  AND token = 'kdB/bruM2oDLbTvFg5sn2YNNodoutQR3DJP6Fx/Pgyo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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