SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '29ed57d969b67578168b1c3618c874d0948fcde6a3a6afc66bba085889896a80' 
  AND token = 'XABRFGQ3IxRCcPl+HRergamOcpEdx8Y7nSYWHh1KqEc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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