SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cb45abc969fa1343e44d6c5fae962a88dfadb55fb9a5ce04867fef785f805818' 
  AND token = 'SAaN9qunsS5OsYL7enKtBZD2rHHcwiZ1VaId9FnYpNE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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