SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '52b2d346ad73a2d455277ede31ed7fce7cdc5b0d7f4079eb0a98d29a44b93342' 
  AND token = 'CF1QjdOOG2phFKF7otbTyE4hoxBtZTH3KeWRTudo66g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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