SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00a14926d566d282b03daf8044d1e99cc7b8f588c433c5e35ad8d52e79448464' 
  AND token = 'YdtizpVPTnFIE+Lu549D4YHivC15DD2TbfUFtu27zFQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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