SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7513883aef21f6cdcce8abafeca2d194cb5942ab061db701543c64eb98972995' 
  AND token = 'Qvz5zniz215QdU/RIg1ZVEyL3/2c0+E27C4E8CNOEj8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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