SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae6dbb643f537d06ae9539bf5266059bbb477a79b13e1a6593a829127b37291a' 
  AND token = 'IjeVJZQAKxEOiIk3fNBfx/2Npa2rhlSn/fDyl7oxfVE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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