SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82aab4f59d8bc881c3bd89f0519aa60c7a34ac78f3926c4d91ec930fb9ee0f81' 
  AND token = 'iLPzkZdiV32fMNiTcZMerR6WHFRipJ2AeXAczrm7bSE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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