SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1b2165ef3ac13596445cd8b9a57ba2bfad13e39ba0cb4420929c6a7dc9c024e4' 
  AND token = 'bx0MuoBi1BPQE4sjwYXxLxXIbA7rysGqHBR9q/2bkLI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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