SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac593cd3922aacedffc49eb357671082f21e197aee4fb8e2ca0cda42910f1adc' 
  AND token = 'zW/+QxOxZ3erDyU0hCez4WAN5Jlvi5OLaOQPK5Jf73E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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