SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3f1af126a40fe363e35a757d8f9430bdfb2bae08c1599637d5da703a1acfa893' 
  AND token = 'vcdROt28sHHalc4rbW2AqtSndmKgrhCUw4v9FYnj3O4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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