SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df10f77164341c6c9abc1bd43ac271eb9b312e128fc462ef86f826de48439f3a' 
  AND token = 'LdIF1FAx7hM9MKEOHphnv9YQyDDYrA6g9o13EIBjfyE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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