SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '48a4276f2b9336c37badae4815cc4a4d4f7c35450fcc0d40702ad801469df005' 
  AND token = 'gysgLcKMjPTSxo9bFZvKzJ4EAsmalJyc/VQ+qmbofxo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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