SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '81cce22e28cca415dbb216e882551862b2353c208313839597e6dedbf3d2e56b' 
  AND token = 'Sv+Gu4KB2qy+GIiSKUcVyRwcBcNpghfegFAW7Mtlgqk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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