SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d7459417943676b62f303455e131bbd83174c52a3a9ba77285458a9912fb418' 
  AND token = 'ucJg6nl+skuj6YTcg1RdD+oSaUD4bU4S2ignD5MhXjQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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