SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f2f59523bdb5c9097aa259c8df2cdbf71008158d7b66555c5ba3bb911192756' 
  AND token = 'ndKLG6/mfoKvKcYLOrNQVLpUXshAT2ufFGqYNFz1T4M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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