SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '102542bc48e0e42b12d66b209f95d42dbe3e8047f84b83d7a6f15b95edf064f6' 
  AND token = 'vWNQa1VG6LNn7eLHore4pKY/MbZOpYbD0HvknjzVzD4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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