SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b1dd2e17dbcf0fa9140e257cbf0aed51d34b13393f1a9b42469f401d463afe22' 
  AND token = 'A9hsCZXtaGWkRkrYyb9t5xruOZoct/+W+2cD6jlSU1s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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