SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b430bcddc808e1756f25ef70522a183ffa821f7b3238d999a894bc5df5eec21' 
  AND token = 'ng9gmXujO97xHdieGLNpnAB63hYMLuovQyrrxmKxoKA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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