SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '382cea31f9714be6502318b21e48d5a12b87885f7f267cfc7d5e09b0af322457' 
  AND token = 'gbvjgWuB7iKO39CEkkCcewvGXtjuC/acS88Soagyocw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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