SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a57a07837eacc37a4b45691a2990abf76d2d9dddcb11a262e9a1d59f3c0be44' 
  AND token = 'rFRGGzZujP6IzDWM1k3QeeD6KgLoEGB+c/cQwU0yYZw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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