SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47dabe2325ecc95280aaf2325894d94a2677a74b94cbbe8d0cabc457d504daa9' 
  AND token = 'Yn+Ei1bgCf0RtNHoKel3r7GC/czAXSsFoavDureWj/8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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