SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b4ce808918e37d98994d683c887478430999ee2d0d3b35418f5f66605947e26' 
  AND token = 'qcsN8rr/gLYcaoUSnh57p3ZYSEJd5DLX8Gzcm99KbtI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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