SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa629d4cd20bdc64085eca3aaf5575094fdbf41ad372c6f045149b573701d225' 
  AND token = '6B7YkUjMC9AtCsFXKfkW9YED0l8aw4sjkmQ9CCA78U0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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