SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e72858c707f940d53e89345acbf344b5a1cd094abf1e798a44c192ae5c82c108' 
  AND token = '7mxis36/PD5+3GFblTy7m+3iYplyqGZ0v5QtA5IcsuI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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