SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14565dd6eec4cf90e070f1d426e1ae51a8142d530c1e64172697dbce3d108aa1' 
  AND token = '0PgCJpiB1dbi6Mk3sx1rQGSPm55KNHWhb9cQkYePftg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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