SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b2436d41498d121d0905d749d7d379666bddd7a84cf05666499d423955b23c40' 
  AND token = 'HMJ6jWhlTFFKRUnh3A3zK3fVQUMU+eNt0rb8Po/2DWg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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