SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e5f7467c7bf95ed790517c2529df64069c4e431a9d29837cd2d832adf2eae01e' 
  AND token = 'zKusY8CfUpqmOkDXZGD+ZxqKrYo/tGfEqkuS/X7ScXw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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