SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06982a650a7375995e40bee9894d3cafa0da72a718f6357dcf51d6f6b8da2789' 
  AND token = 'Z/I+StFVqSMx6WEuJzXTKixQZOV8s2J+w/GQ7ssLsUU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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