SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '215638e1c015ef14c33f70d748416819a3d818e0d767a5484eebf0f2f0532eb1' 
  AND token = 's/3lUbMrG9q0Bc3QAOvBChNpHfJjKFdRlo8LuMAi7pk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}