SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'abfd284d550dbce45daf92cff5271b86c648287c89b2a57252bd3440b9f550eb' 
  AND token = 'X3SVIQG6gJh9mVkjh9UqvitZk0iN/ZtWI8kwTuFfnLU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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