SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd7bed2f6d6ca92c89784bdbaf345fc1d354ce19bb5e2f5add644078e2bee5a7f' 
  AND token = 'bCCHJyK5R0Fex/ah4c8n0RwmXXCcbROEgOLcEV6uPUU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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