SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58532c1f7da3e6fea415825c4f0ab4de98b7152a9df78d373262638c5af2729f' 
  AND token = 'tMaPJO/bDWxFU4UeJwPTI53sOS2HpRmdCv8Bj/yVBhQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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