SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06dcd558f9f53c363e0703d4aef33f9c7e59adf7854398afe7a7b1144d0a2434' 
  AND token = 'dpN0eA7KFuQDBta3L3klY5hXTCHNqJVV+EeHtdaRnWw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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