SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ff9372de8a129cb39846b93913bd1c88fd7f90fa2c61091ddb90d2fffab4ecc9' 
  AND token = '7RvO+10RMvDJs1oRnhoQHpELrt7VlHvsAG/lnxbRzwE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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