SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae7dcd5fba32c50e2450f86e2eb4e99092112b3816403f42ae56ad10e59ea5a8' 
  AND token = 'bvcU630MZ1RREc13NlHzdvap3MqneGHx+Dl/m5iijq4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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