SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d04001b6819ad0f676ed28c4d20b0e11c07f92a9b9cad45debebbb4bc661582' 
  AND token = 'nin0rj4ALilbIiIKvzeMTwTac0jaFOkOh+h9AcKRkRg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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