SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7aadf73451b812ba97f9c4ed675623034432bc38d21d57e60dd19d85e4a01861' 
  AND token = '+spZDOCTlawEdgHPn0R06KOGZ9GvU5h1TjuvLDdRMls=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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