SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '86bd2d2ac47360ffa2a60e6ff60d41d0aa5fc61b4f259531fb9b9bd4b29c46ac' 
  AND token = 'C3vLiW8gmCJxezzuNQX3Vtyw9b7BQH4klWWwxRDIgKU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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