SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d910360688ecd842342c2646ed8d0b92d925073c57090668fec6ac951bb2105' 
  AND token = 'IJX1o0VngEcQXqzznDZSa93ExdmEUBqtrlL7bwt2j1A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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