SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f2b3f3c6c987d031f41da3e7dac8d692b38244d6ee0b9312e88903633f37371e' 
  AND token = 'ahDOyCxa4Z92CAwgwWpzd5H86ieWToE9bAbcYciKeeE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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