SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82942637de19fec59085769ac27f5bafef4059aa878c649ccef452e9f97e21de' 
  AND token = 'cWI4hug8AqDE/1zLaDtGpNn3kFQfAd/NVEvo6K188Bc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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