SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '464d38f6539e6728831094ab5595a7a55f2b6cbb92c95592d7a33618a26164e7' 
  AND token = '/fwUBpgOp+/qZns46/wz/g8slA+rJ1hzrz9LjXH8FpM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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