SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06c9d2a95e72503f91f2a0fbf76602227a218f114631eda09ae868ba48a12c42' 
  AND token = 'l4l8GV+PFKThzC5pQ3+M4rL0PdZEmRJhMaJDoVstIEM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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