SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '720091fd44de62671c4203d8abee649d503a1d61f41fa468aef78d8df363c319' 
  AND token = '74DbZwBYXaxvYMMI8KWa3gjGaYXqTNBMuy3cTz0Gonw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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