SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '7f1ca9b317f2d812370f44b5c9056e21cb77f3c25d60157d974d7eef57c476c5' 
  AND token = '3MMQTSCia+JNBkIhWQoVLPYaJ+3pyaOkMFtni4wkSUs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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