SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4726512339a0f0697ab2271a9485cdedb5ca12c6d5f03e897e5ebdf00f2b3797' 
  AND token = '/4OooNg86HrzZvyzEJXSPeoSf0FLQcnAMpP6LEvoSzs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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