SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f36d02e12ce9e08391bf11318d56c17583ee944f7e66f319226ab81bddc55fed' 
  AND token = 'KKyPg6xcAcH8E381j/vCsxslw66SK8E2uYiWZ2jWYTw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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