SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5cad797911eb67f8ed8ad082a2dfa49486710b9d895a42cf0eca4ce4aed41b1b' 
  AND token = 'mZ7qKvrlXGMapLn2g0oitPijyMnXfhtgU469vsQ4TbY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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