SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65aa9760602db039261db148e029bbe5a081cf5e14d7b2a995b057704242661e' 
  AND token = 'xjddZ6v525NzOc81nAD6bTcTjM+aErBNmtGdJy3+l9o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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