Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a955371d80b45e54bf9c4f54bd5acf3f3d62005fdb5f9813a4165dde85a1505c' 
  AND token = 'arhNA9Z+H2xmWd6QBrZYAcV1Ftb4Wxu6vjiIbGuYjO0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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