SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3054ac90f0429d586226fc5dc45a98e647fbf18bdabb9d9ae2da1611ab3852cc' 
  AND token = '627X2xIIbKiYKEd6VAuXCXPbFpmilB6uqL/B1Nwp/hg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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