SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b9393019ff4f6062d75c34d9c4666058cfa0e26dabc67533fba490ad9d6ae043' 
  AND token = 'uA28YLsYBP7KxZKBxeF3Jg8GDki/oVTojSNts/LTDFQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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