SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '526258f662f1a276bfd9dba5a02f9db074885a347a58624dda5cbd94c2729852' 
  AND token = 'Faomu//C+HAOtrj50JkUElCzq4+QVAf4S6YutvbMCrY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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