SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ec896ce71c4d062b5673423059ddeb5f6975e418914930bc135b62e26c67c75e' 
  AND token = 'jEC8QviiJEY9mKK6Nx0ZJCmGzL489yk2OT6ku9YmvAw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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