SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b6be0d84263c2c0d703e11620dd08f9035bbb65f7e57662b67f29a8038ca99df' 
  AND token = '/5Zd3l2V8FlT+zQS1Dm7zmYfn9mqAoHTVtjw05+jKYQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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