SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3513bd881f7db12d070319e3c4110aacf45d07b8e95067ae1c3d04beb356a064' 
  AND token = 'BxTMqmvE752K+opfYXYQBncH6gDMkpgNTFdAy4bUB1Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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