SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41139ddb99175957c8697b6e9d31bcc6ab1744827437b6621b6380a18ea54e1d' 
  AND token = 'oJbAAA//fNLLcRB76l1xDi3JzDPFVKaIGKGCGrEKN0o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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