SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06b697b6ba2b6d72c8a0b49a507c262dfb1b93729abfd745a312367c5cd5dd92' 
  AND token = 'td0nVZAc1D7S2yrAlxGvDy3MmPhiReOXuUGrMwv1kH0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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