SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd0caefd6b91b1c005b8d83c230b7ac9ae63e8450447586e3b8360d97b9532350' 
  AND token = 'Y/dcoiWpYyIMzCnfS6pok66kRWciiTHRcKC/hHt8fg4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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