SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a917a1a8bab79d28f31a362fe99b65fa62139efc155aeed1ad682f40aa323992' 
  AND token = '/O1xjZR0ZNs0QyyQ6M2WUAVbchAQaAYbimFa4h8kj1I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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