SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e3ce49d0d9f6607979a835ad9a6ca0766e6bb80fa3ee7eb3be293086a145101' 
  AND token = '4bgs+oxJl/X4DC+xNGc6B/pk3KDvpi5iE2mHWnFISA4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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