SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e1407333738ae87d91ee5cdbee9bd8629970efa9d3eaf2054b6231d015c8874' 
  AND token = 'HsEtYVcIaMkVLRYk5y4Sx/1GUkylCULT23yGIzRnRqs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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