SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd330697bc66e5293264a8e62c6d230ceaf06321fdbb489a7c749767ec1a29048' 
  AND token = 't1BJ1KBUNbplnoQPmBQlGuYCqOxysw/F4YL2QmDlDjs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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