SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5bd2c620f7683ee88b9746a54af6b710b85528e9d77d168a7410dcdff8282cb3' 
  AND token = 'AWQJFhXdIKQ5+iaYYmXpTyY/qlMd9V9M5erwpjuqOVw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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