SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb09689780a81ff37d0080370ff2771ececa47821748dfdb22024f46524e0427' 
  AND token = 'phm342PiKdq7DPPkhUWC1do8zjggbjHgvmflIqLm2vE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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