SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '103bbe4557e45c6c063fc9b2b61ac90dba891128a5d8815d3b7df0a7f7b60ea2' 
  AND token = '+UKs27qPuBCmBgaGHKOEMsz/p8V8RZcY2/+gl9os5uc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}