SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2bce4a672a1f02cbe894a53d371ffc359d995c54684eafdb1b94af795c5781d6' 
  AND token = 'GBatPAyZu0X0lMmSYvrMJBVJFnAYK1BELnmfAf12s6Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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