SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59413d5a8a6585ec6dd9af3699cb48ac7c84541d85a12fb8776d39738f321337' 
  AND token = '2wLpgnz9FKM0dBHxvGdgkV/6kY5SDQ4ZlCyyIDNSRtM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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