SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '18f32ecf43917be7bb40782414868e8ced291733fbaba79c7af7a2796c97f1c9' 
  AND token = 'fUCPjEZUntc7SK0IQ+oc1UL3Ztbj+d04VLKK2kFCOZc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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