SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c569a9faef992480b47cf643c377ec90b89094de14ba4ea4ea01c2dea37165a5' 
  AND token = 'u8/64ALdhpY/gNpIXppj0VLFFZxiXh37baf9nnIMmto=' 
  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"
    }
  }
}