SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '993fc2210a53acc79383722491a78c5bbfb3df3044c72b6253bafc4c4825678e' 
  AND token = 'uqLqS/IZetXWZQAL+J06+VZzyEu0zN04UWP/a8OCn80=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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