SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9f36cd1e97839f9d8d84d26980e83846d601abc0348070e4c824261247a7932e' 
  AND token = 'LLnAYzakjIrSKsJETHbLxnIMzsaCTJRsum9nQyUZZC0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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