SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6a26430a2fd6e7f177d09d9fbfb042c2109893c2e1fbdefbf6788199e58167cd' 
  AND token = 'L8P9FjN4pkZR4TVoG/Flg1s4XRMhJBNk0hkOCCq0Kwo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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