SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '909ddf89b6e71709d4edd714e0b3d891cb888bc1673e25446f6ba2b7d54551db' 
  AND token = 'yGQWI6es8htSBDtNNeFU7ysra2+GZrXVaoqhRZdjJpk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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