SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70c590ce8c9b4d35fceec335600fa67741054451e2370c3a973d9080760d3599' 
  AND token = 'd0EzPGclt0/7n/vw2ziC5TkzbpuKa1YppcwdB/qdHxA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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