SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1bf3e34ba60b054625ee4bc35d7d29e9cd52841a096da3993b507219750eaa3e' 
  AND token = 'TvlnvcHrZza5ABaRF4pAw/mDqJUZ0njCjfvPYThP3Lc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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