SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '84610e8b338c504a352bf7e5bee4362044748d9d9baaf779e99801ed11fba8f5' 
  AND token = 'kbwivoSTDIEFZqqYnqzvZ6pr7SxwM2exkOQdq0S/6n0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00087

JSON explain

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