SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f131971f3d1f8c5b56233f1074856fcc5d07651b4aa02386f0ae208a6328c6fc' 
  AND token = 'dhbBbZR4qVuuoKSjRBc/SoJYkAd4/K/XPG+wS4j5zi8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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