SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ab4e3e1a0ea484663529aa6f228603a002e27b704ececbfae0872931888cdd9' 
  AND token = 'X0D88oVKRwe2/dPPpURsttBI1XXtNc4Joyc2UDIIg04=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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