SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eee44eca40af8e33ab20483d15efa2878255850615fef7583f7840d014883cc1' 
  AND token = 'QSdXNijsSgoW9VwlHNasY6/ZM5ACj2mVXkUWALXTNKg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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