SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '00435f78c489aaa5e42f2c93599e7eedbcc134fae6da1c24bada3770e400c60f' 
  AND token = 'BuARBnhtFuDiVMd0yoPcqdaUb5g4Liwd/hXts+ffv8k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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