SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c63271b64e6e073bcd0e4df1f685d51067e1b808dc13feec1ea3501e243486a6' 
  AND token = 'VyuRz9WW8LJQO+ugGULgFxRxiE14OPBT4AVh/NoRuXY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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