SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8680734f18bf23529843cb32220e4b4786260b2e63af5f9250563355c67f14ab' 
  AND token = 'yJTBwC0GNNp8Jcg8QplosBoIUnpyLigMSuCbWL/bF/g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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