SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54e9b4f48ba31a09cc85d94924a27c5e46adbe56ee741453a17f297ba3277c92' 
  AND token = 'whIDiGDzNSc18Y2zy8H+pvQ/ndmBCkIlipxKz4rKFHo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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