SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7535e2ea2adcad945796ae7ac3e96cc46fc27aa7b230aa326d0d281154d51ace' 
  AND token = 'CRoRBMb4Wdh5Abq5/PmbJXxEkbZJTNNAtNcFyqJJ9MI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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