SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8aef801849aebaf53dce89f98a5f2b2ced002e7cc2911db1417830998ae62aff' 
  AND token = 'ItAgTVyHpfX1UvCKHBCCwoxThOm5JnvHqerglZJ6kqU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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