SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd260f32da6d0482e560ec3e00514bc53991cc06baeeac8d330d11417bf96d68f' 
  AND token = '0x2HoFRcjPzWttmzm7Br4Xl7lZfr8Ow0jyk1kYbo42Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}