SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c8177d1640c9e676377141b801b54e75a88cce4c5d8848f275a3ffb8488d8e3' 
  AND token = 'nD0biE9wNs+KEG2OGEIx+NaQFpzLH0e1olPe+uJj3RU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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