SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d1be47841b2991d681ae54659c82d912b94c0bdd163581394ba8885f2237ceb' 
  AND token = 'Wn4qw2p5ej5GdyOiCTtvYO32BFJgZRmvdD0DsDQ+OrY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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