SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ebc818c6468bd2f06853004ab7a1c803398d978b442e1a5446cbe5f8c13b50fb' 
  AND token = '0mMwh3vOUtmi9hHB9k6DcqUAFuRQCZjLrxw079oDkDw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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