SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2b184db6201dfbf500e7f93381da8990e6300ec87656e6a8634276c6e7fb6f3' 
  AND token = 'AHqR/yMY8gontoVlkAB/5IgFVbJkxqJBPwK+n3Rw/C0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}