SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9186e7ddd728973e45dbc98a7c8143c7972267cf0939a89d846ca575f16ba7cf' 
  AND token = 'xLKoQVW9Vir4EPY8jsb8X14X2hBzaniBX6Y0ZrSgDy4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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