SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7886511fe1127bdb00faed9b10a7419263c9bbb0ee594960a196434c48133723' 
  AND token = 'L5N5caIUp90f3WE5lzkiNk6O9J0GFGostBnS5rTlTVY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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