SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a3c7937dad56cd66f5c3ed80a94f3ede78dd24bc989c828d64f35814266668ed' 
  AND token = 'phxQGWTJOQAsJGI6+hpIYetatO4ba+3bnyYimJbAAHk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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