SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e6d6a51e59c2e78d12d7692b30da29634de67a94e5eb54275d3aa3d82082771b' 
  AND token = 'mUL46JHNuZhIg//1vpQSnawYBwclxcF2efES4izyJqk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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