SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '259008a6a6f54e6f90cb88a7e62e8632afca7cd0480c052672854968d8117a9f' 
  AND token = 'WvL+dtSGl52OkMt6J3ujcbzIr6fPikpjn/xfmI1ZIZk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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