SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6adb161b3872bf06a3d8b66437e7c046a32217c9308aa5376003e306152d2217' 
  AND token = 'hUPdItQXrKsXBAdvWsW7GthFITZX3GwSBTs3DXMuo+o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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