SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc8fafe01410f0c59fe7c67c08158a016ead54dac50b07fe928b0aa22404cf85' 
  AND token = 'Za5z1YjfSaAohZTxJ4ldkF2APsBgEr+7rDrKi4z1HMk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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