SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e8768dbda79d258fb7ca7771e14ecff9d16c39f44b446f21423a90ee6643ad9' 
  AND token = 'ABppgwsD4D5jb1vNV+RzxqSjSsrRDIhd2DVpopqHWJ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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